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Mohd Nor Ihsan NS, Abdul Sani SF, Looi LM, Pathmanathan D, Cheah PL, Chiew SF, Bradley DA. EDXRF and the relative presence of K, Ca, Fe and as in amyloidogenic tissues. Spectrochim Acta A Mol Biomol Spectrosc 2024; 308:123743. [PMID: 38113556 DOI: 10.1016/j.saa.2023.123743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 11/09/2023] [Accepted: 12/07/2023] [Indexed: 12/21/2023]
Abstract
Trace and minor elements play crucial roles in a variety of biological processes, including amyloid fibrils formation. Mechanisms include activation or inhibition of enzymatic reactions, competition between elements and metal proteins for binding positions, also changes to the permeability of cellular membranes. These may influence carcinogenic processes, with trace and minor element concentrations in normal and amyloid tissues potentially aiding in cancer diagnosis and etiology. With the analytical capability of the spectroscopic technique X-ray fluorescence (XRF), this can be used to detect and quantify the presence of elements in amyloid characterization, two of the trace elements known to be associated with amyloid fibrils. In present work, involving samples from a total of 22 subjects, samples of normal and amyloid-containing tissues of heart, kidney, thyroid, and other tissue organs were obtained, analyzed via energy-dispersive X-ray fluorescence (EDXRF). The elemental distribution of potassium (K), calcium (Ca), arsenic (As), and iron (Fe) was examined in both normal and amyloidogenic tissues using perpetual thin slices. In amyloidogenic tissues the levels of K, Ca, and Fe were found to be less than in corresponding normal tissues. Moreover, the presence of As was only observed in amyloidogenic samples; in a few cases in which there was an absence of As, amyloid samples were found to contain Fe. Analysis of arsenic in amyloid plaques has previously been difficult, often producing contradictory results. Using the present EDXRF facility we could distinguish between amyloidogenic and normal samples, with potential correlations in respect of the presence or concentration of specific elements.
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Affiliation(s)
- N S Mohd Nor Ihsan
- Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - S F Abdul Sani
- Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - L M Looi
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Dharini Pathmanathan
- Institute of Mathematical Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - P L Cheah
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - S F Chiew
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - D A Bradley
- Sunway University, Centre for Applied Physics and Radiation Technologies, Jalan Universiti, 46150 PJ, Malaysia; School of Mathematics and Physics, University of Surrey, Guildford GU2 7XH, UK
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Chiew SF, Toh YF, Looi LM, Cheah PL. Gastrointestinal stromal tumour in a jejunal diverticulum: The eighth reported case worldwide with a brief review of the literature. Malays J Pathol 2023; 45:473-478. [PMID: 38155388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2023]
Abstract
Jejunal diverticulosis is uncommon and so are gastrointestinal stromal tumours (GIST) arising in the jejunum. GIST arising in a jejunal diverticulum is a rarity and to date there are only 7 cases in the English literature. Our case of GIST occurring in a jejunal diverticulum of a 48-year-old lady would be the first reported in Malaysia and the 8th in the world. As in most cases, the clinical presentation and radiological findings of this patient were non-specific. With a history of acute abdominal pain, vomiting and fever, the patient was provisionally diagnosed as a case of twisted ovarian cyst and subjected to laparotomy. An intact roundish jejunal diverticulum 5.0 cm x 5.0 cm, about 50 cm distal to the duodeno-jejunal junction was found and resected with a segment of small intestine. Microscopic examination showed a tumour of the cut open diverticular wall, with epithelioid to spindled cells, demonstrating a mitotic rate of 1-2 per 5 mm2, confined to, while infiltrating the wall of the diverticulum. The immunohistochemical profile of positive staining for CD117, DOG-1, smooth muscle actin and CD34, and negative expression of desmin and S100 protein, clinched the diagnosis of GIST. Based on the AFIP Criteria for risk stratification,1 the patient was categorised as having moderate risk for disease progression, and was not offered further targeted imatinib as an immediate measure. The patient has remained well at the time of writing i.e. 8 months following excision, and continues on active surveillance by the surgical and oncological teams, with the option of imatinib, should the necessity arise. This case is presented not merely for the sake of documenting its rarity, but as a reminder to stay alert for uncommon conditions in histopathology practice.
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Affiliation(s)
- S F Chiew
- University of Malaya Medical Centre, Department of Pathology, Kuala Lumpur, Malaysia.
| | - Y F Toh
- University of Malaya, Department of Pathology, Kuala Lumpur, Malaysia
| | - L M Looi
- University of Malaya, Department of Pathology, Kuala Lumpur, Malaysia
| | - P L Cheah
- University of Malaya, Department of Pathology, Kuala Lumpur, Malaysia
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Chiew SF, Looi LM, Cheah PL, Teoh KH, Chang SW, Abdul Sani SF. Epithelial-mesenchymal transition profiles in triple negative breast carcinoma may explain its aggressive nature. Malays J Pathol 2023; 45:363-374. [PMID: 38155378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2023]
Abstract
Epithelial-mesenchymal transition (EMT) is increasingly explored in cancer progression. Considering that triple negative (TN) breast cancer has the poorest survival among molecular subtypes, we investigated 49 TN, 45 luminal and 25 HER2-enriched female breast carcinomas for EMT expression (using E-cadherin and vimentin immunohistochemistry) against lymphovascular and/or lymph node invasion. E-cadherin and vimentin expressions were semi-quantitated for positive- cancer cells (0=0-<1%, 1=1-10%, 2 =11-50%, 3=>50%) and staining intensity (0=negative, 1=weak, 2=moderate, 3=strong), with final score (low=0-4 and high=6-9) derived by multiplying percentage and intensity scores for each marker. Low E-cadherin and/or high vimentin scores defined EMT positivity. Low E-cadherin co-existing with high vimentin defined "complete" (EMT-CV), while low E-cadherin (EMT-C) or high vimentin (EMT-V) occurring independently defined "partial" subsets. 38 (31.9%) cancers expressed EMT, while 59.2 % TN, 13.3% luminal and 12% HER2-enriched cancers expressed EMT (p<0.05). Among the cancers with lymphovascular and/or lymph node invasion, EMT positivity by molecular types were 66.7% TN, 7.4% luminal and 11.8% HER2-enriched (p<0.05). Although EMT-V, associated with stem-cell properties was the dominant TN EMT profile, EMT-CV, a profile linked to vascular metastases, was encountered only in TN. EMT appears important in TN cancer and different EMT profiles may be associated with its aggressive nature.
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Affiliation(s)
- S F Chiew
- University of Malaya Medical Centre, Department of Pathology, 59100 Kuala Lumpur, Malaysia.
| | - L M Looi
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Malaysia
| | - P L Cheah
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Malaysia
| | - K H Teoh
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Malaysia
| | - S W Chang
- Institute of Biological Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - S F Abdul Sani
- University of Malaya, Faculty of Science, Department of Physics, 50603 Kuala Lumpur, Malaysia
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Mohd Nor Ihsan NS, Abdul Sani SF, Looi LM, Cheah PL, Chiew SF, Pathmanathan D, Bradley DA. A review: Exploring the metabolic and structural characterisation of beta pleated amyloid fibril in human tissue using Raman spectrometry and SAXS. Prog Biophys Mol Biol 2023:S0079-6107(23)00059-7. [PMID: 37307955 DOI: 10.1016/j.pbiomolbio.2023.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 05/12/2023] [Accepted: 06/09/2023] [Indexed: 06/14/2023]
Abstract
Amyloidosis is a deleterious condition caused by abnormal amyloid fibril build-up in living tissues. To date, 42 proteins that are linked to amyloid fibrils have been discovered. Amyloid fibril structure variation can affect the severity, progression rate, or clinical symptoms of amyloidosis. Since amyloid fibril build-up is the primary pathological basis for various neurodegenerative illnesses, characterization of these deadly proteins, particularly utilising optical techniques have been a focus. Spectroscopy techniques provide significant non-invasive platforms for the investigation of the structure and conformation of amyloid fibrils, offering a wide spectrum of analyses ranging from nanometric to micrometric size scales. Even though this area of study has been intensively explored, there still remain aspects of amyloid fibrillization that are not fully known, a matter hindering progress in treating and curing amyloidosis. This review aims to provide recent updates and comprehensive information on optical techniques for metabolic and proteomic characterization of β-pleated amyloid fibrils found in human tissue with thorough literature analysis of publications. Raman spectroscopy and SAXS are well established experimental methods for study of structural properties of biomaterials. With suitable models, they offer extended information for valid proteomic analysis under physiologically relevant conditions. This review points to evidence that despite limitations, these techniques are able to provide for the necessary output and proteomics indication in order to extrapolate the aetiology of amyloid fibrils for reliable diagnostic purposes. Our metabolic database may also contribute to elucidating the nature and function of the amyloid proteome in development and clearance of amyloid diseases.
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Affiliation(s)
- N S Mohd Nor Ihsan
- Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - S F Abdul Sani
- Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - L M Looi
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - P L Cheah
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - S F Chiew
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Dharini Pathmanathan
- Institute of Mathematical Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - D A Bradley
- Centre for Applied Physics and Radiation Technologies, Sunway University, 46150 PJ, Malaysia; Department of Physics, School of Mathematics & Physics, University of Surrey, Guildford, GU2 7XH, UK
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Kong PL, Looi LM, Cheah PL. Potential utility of telomere length assessment in breast cancer in a diagnostic histopathology setting. Malays J Pathol 2023; 45:51-63. [PMID: 37119246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
INTRODUCTION Telomeres shorten with cell cycling but are restored above mortality threshold in many cancers making them potentially exploitable for differentiating malignant from benign tissues, and for cancer evaluation. MATERIALS AND METHODS We assessed telomeres in a diagnostic histopathology setting using quantitative fluorescence in situ hybridisation on 33 fibroadenoma (FA) and 73 invasive breast carcinoma of no special type (IBC-NST) (prototypes of benign and malignant breast tumours, respectively) with paired benign, non-lesional breast tissues (BNL). Telomere lengths were expressed as telomere/chromosome-2-centromere ratio (TCR). The telomere length cut-off for malignancy was also determined. RESULTS Mean TCR of IBC-NST was significantly shorter than FA and BNL (p<0.001). Mean TCR of FA was shorter than BNL but not significantly (p>0.05). TCR cut-off for IBC-NST based on FA was ≤0.29 (sensitivity=75.3%; specificity=78.8%), and ≤0.30 based on BNL (sensitivity=76.7%; specificity=89.0%). TCR of IBC-NST did not differ in relation to histological grade, nodal and hormonal status (p>0.05) but was significantly shorter in HER2-overexpressing cancers (p<0.05). CONCLUSION We have demonstrated a first-step to the development of methodologybased cut-off values of mean telomere length for distinguishing benign from malignant breast tissues. Telomere length may not value-add to the standard prognostic and predictive parameters, but has potential in relation to HER2.
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Affiliation(s)
- P L Kong
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Federal Territory, Malaysia
| | - L M Looi
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Federal Territory, Malaysia.
| | - P L Cheah
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Federal Territory, Malaysia
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Tham JH, Looi LM, Ghazali R. Cost analysis of pathology services comparing conventional 6-core transrectal biopsy versus transperineal saturation biopsy in diagnosing prostate cancer. Malays J Pathol 2022; 44:469-475. [PMID: 36591714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
INTRODUCTION Patients who are suspected of having prostate cancer from screening tests require a tissue biopsy to confirm the presence of cancer. This study aims to compare the cost and cancer detection rate of two different biopsy protocols: 6-core transrectal (TR) approach, and transperineal (TP) saturation biopsy. METHODS In this descriptive, retrospective study, we selected all prostate biopsies received by the diagnostic pathology department of a tertiary hospital in Malaysia in the year 2020, from adult patients for analysis. Data on demographics, specimen preparation processes, and final histopathological diagnosis was extracted from the Laboratory Information System (LIS). The cost incurred for each biopsy diagnosed as cancer was calculated with the cost prices referenced from laboratory documentation. Statistical analysis was performed using SPSS, version 28. RESULTS The total cost for detection of cancer using TR biopsy ranged from RM11.22 - RM271.02 with mean of RM47.53. The standard deviation, s is RM43.45. For TP biopsies, the total cost ranged from RM112.20 - RM349.56 with mean of RM160.85, standard deviation of RM80.37. TR biopsies had a detection rate of 43.2%, while TP biopsies had a 24.2% cancer detection rate. There is a 3.38-fold increase in costs between TR and TP biopsy. CONCLUSION The results show a 3.38-fold increase in costs and a reduction in cancer detection rate when comparing TR and TP biopsy. The reason for the reduced detection rate is unascertained in this study.
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Affiliation(s)
- J H Tham
- Hospital Kuala Lumpur, Histopathology Unit, Dept. of Pathology, Malaysia.
| | - L M Looi
- University of Malaya, Faculty of Medicine, Department of Pathology, Kuala Lumpur, Malaysia
| | - R Ghazali
- Hospital Kuala Lumpur, Histopathology Unit, Dept. of Pathology, Malaysia
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Wong YP, Abu Backer FM, Tan GC, Looi LM, Mat Salleh MJ, A Subramaniam PA, Rahimi R, Ariffin R, Razali RH, Siew SF, Cheong SK, C Thambiah S, Md Hanapiah S, Kumariah T, Tang YL, Zainol Rashid Z. Guidelines on retention of pathology records and materials (Version 2/2022). Malays J Pathol 2022; 44:165-176. [PMID: 36043580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
No abstract available.
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Affiliation(s)
- Y P Wong
- Universiti Kebangsaan Malaysia, Faculty of Medicine, Department of Pathology, Kuala Lumpur, Malaysia.
| | - F M Abu Backer
- Hospital Sultan Abdul Halim, Department of Pathology, 08000 Sungai Petani, Kedah, Malaysia
| | - G C Tan
- Universiti Kebangsaan Malaysia, Faculty of Medicine, Department of Pathology, Kuala Lumpur, Malaysia
| | - L M Looi
- University of Malaya, Faculty of Medicine, Department of Pathology, Kuala Lumpur, Malaysia
| | - M J Mat Salleh
- Hospital Seberang Jaya, Department of Pathology, 13700 Permatang, Malaysia
| | - P A A Subramaniam
- Palani Ammal & Co., Suite 7-5, 2 Rio Tower, 47100 Puchong, Selangor, Malaysia
| | - R Rahimi
- Universiti Teknologi MARA, Faculty of Medicine, Department of Forensic Pathology, 47000 Sungai Buloh, Selangor, Malaysia
| | - R Ariffin
- Hospital Tunku Azizah, Department of Pathology, Genetics Laboratory, 50300 Kuala Lumpur, Malaysia
| | - R H Razali
- Universiti Teknologi MARA, Faculty of Medicine, Department of Pathology, 47000 Sungai Buloh, Selangor, Malaysia
| | - S F Siew
- Hospital Kuala Lumpur, National Institute of Forensic Medicine, 50586 Kuala Lumpur, Malaysia
| | - S K Cheong
- Universiti Tunku Abdul Rahman, Faculty of Medicine and Health Sciences, 43000 Kajang, Selangor, Malaysia
| | - S C Thambiah
- Universiti Putra Malaysia, Department of Pathology, Faculty of Medicine and Health Sciences, 43400 Serdang, Selangor, Malaysia
| | - S Md Hanapiah
- National Cancer Institute, Department of Pathology, 62250 Putrajaya, Malaysia
| | - T Kumariah
- Hospital Kuala Lumpur, Department of Pathology, 50586 Kuala Lumpur, Malaysia
| | - Y L Tang
- Universiti Kebangsaan Malaysia, Faculty of Medicine, Department of Pathology, Kuala Lumpur, Malaysia
| | - Z Zainol Rashid
- Universiti Kebangsaan Malaysia, Faculty of Medicine, Department of Medical Microbiology and Immunology, Kuala Lumpur, Malaysia
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Cheah PL, Chau YT, Looi LM. Immunohistochemistry usage profile in a Malaysian tertiary hospital's histopathology laboratory. Malays J Pathol 2021; 43:353-359. [PMID: 34958056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
INTRODUCTION Immunohistochemistry (IHC) was commenced in 1986 at the Department of Pathology, University of Malaya Medical Centre, Kuala Lumpur and its usage has grown for the past 30 over years, hence it was felt that a review was timely in view of the scarcity of literature on IHC usage. MATERIALS AND METHODS All cases received by the Department of Pathology for histopathological examination between 1 July 2018 and 30 June 2019 were retrieved from the Laboratory Information System (LIS). All the IHC requests over this period were tabulated, with the exception of renal, muscle, rectal and nerve biopsies with their pre-defined algorithms for stains and cytological specimens. IHC stains performed solely for purpose of directing targeted treatment were also not included. RESULTS Immunohistochemistry was performed in 2044 (21.1%) of the total of 9686 cases, with a total of 5969 IHC stains performed i.e. 2.9 (5969/2044) IHC stains per case. All 91 antibodies available were used at least once during the study. 14 histopathologists (5 with < 10-years and 9 with ≥ 10-years postgraduate specialist experience) reported on the cases with no significant difference (p=0.90) in their usage of IHC stains. Among the most common IHC stains used, requests for Ki67 and MNF116 showed higher standard deviations compared with p63, CK7 and S100 among the histopathologists. From the relatively higher standard deviation for Ki67 and MNF116 it appeared that there was a greater difference in the requesting pattern between histopathologists for these two antibodies. CONCLUSION The rate of use of IHC in our centre seems compatible with that of an academic centre. Personal preferences of the histopathologists, rather than years of postgraduate specialist experience appeared to influence the rate of usage and choice of antibodies.
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Affiliation(s)
- P L Cheah
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Malaysia.
| | - Y T Chau
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Malaysia
| | - L M Looi
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Malaysia
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Sabtu SN, Sani SFA, Looi LM, Chiew SF, Pathmanathan D, Bradley DA, Osman Z. Indication of high lipid content in epithelial-mesenchymal transitions of breast tissues. Sci Rep 2021; 11:3250. [PMID: 33547362 PMCID: PMC7864999 DOI: 10.1038/s41598-021-81426-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 12/21/2020] [Indexed: 02/06/2023] Open
Abstract
The epithelial-mesenchymal transition (EMT) is a crucial process in cancer progression and metastasis. Study of metabolic changes during the EMT process is important in seeking to understand the biochemical changes associated with cancer progression, not least in scoping for therapeutic strategies aimed at targeting EMT. Due to the potential for high sensitivity and specificity, Raman spectroscopy was used here to study the metabolic changes associated with EMT in human breast cancer tissue. For Raman spectroscopy measurements, tissue from 23 patients were collected, comprising non-lesional, EMT and non-EMT formalin-fixed and paraffin embedded breast cancer samples. Analysis was made in the fingerprint Raman spectra region (600-1800 cm-1) best associated with cancer progression biochemical changes in lipid, protein and nucleic acids. The ANOVA test followed by the Tukey's multiple comparisons test were conducted to see if there existed differences between non-lesional, EMT and non-EMT breast tissue for Raman spectroscopy measurements. Results revealed that significant differences were evident in terms of intensity between the non-lesional and EMT samples, as well as the EMT and non-EMT samples. Multivariate analysis involving independent component analysis, Principal component analysis and non-negative least square were used to analyse the Raman spectra data. The results show significant differences between EMT and non-EMT cancers in lipid, protein, and nucleic acids. This study demonstrated the capability of Raman spectroscopy supported by multivariate analysis in analysing metabolic changes in EMT breast cancer tissue.
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Affiliation(s)
- Siti Norbaini Sabtu
- Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - S F Abdul Sani
- Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - L M Looi
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - S F Chiew
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Dharini Pathmanathan
- Institute of Mathematical Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - D A Bradley
- Centre for Biomedical Physics, Sunway University, Jalan Universiti, 46150, Petaling Jaya, Malaysia
- Department of Physics, University of Surrey, Guildford, GU2 7XH, UK
| | - Z Osman
- Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
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Kong PL, Cheah PL, Mun KS, Chiew SF, Lau TP, Koh CC, Teoh KH, Nazarina AR, Looi LM. FISHing for 1p19q codel in oligodendroglioma. Malays J Pathol 2020; 42:369-376. [PMID: 33361717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Together with isocitrate dehydrogenase (IDH) mutation, co-deletion of 1p19q (1p19q codel) is a prerequisite for diagnosis of oligodendroglioma, making it imperative that histopathology laboratories introduce testing for 1p19q codel. To date there is still no consensus reference range and cut-offs that confirm deletion of 1p or 19q. We embarked on determining our reference range in 11 formalinfixed, paraffin-embedded non-neoplastic brain tissue using fluorescence in situ hybridisation (FISH) with the Vysis 1p36/1q25 and 19q13/19p13 FISH Probe Kit (Abbott Molecular Inc., USA). At same time we attempted to validate our methodology in 13 histologically-confirmed IDH-mutant oligodendrogliomas. For 1p, percentage cells with deletion (range=8-23%; mean±SD = 15.73±5.50%) and target: control (1p36:1q25) ratio (range = 0.89-0.96; mean±SD = 0.92±0.03) in non-neoplastic brain, differed significantly (p<0.000) from oligodendroglioma (percentage cells with deletion: range = 49-100%; mean±SD = 82.46±15.21%; target:control ratio range:0.50-0.76; mean±SD = 0.59±0.08). For 19q, percentage cells with deletion (range = 7-20%; mean±SD = 12.00±3.49%) and target:control (19q13/19p13) ratio (range:0.90-0.97; mean±SD = 0.94±0.02) in non-neoplastic brain also differed significantly from oligodendroglioma (percentage cells with deletion: range = 45-100%; mean±SD = 82.62±18.13%; target:control ratio range:0.50-0.78; mean±SD = 0.59±0.09). Using recommended calculation method, for diagnosis of 1p deletion, percentage of cells showing deletion should be >32-33% and/or target:control ratio <0.83. For 19q, percentage of cells showing deletion should be >22% and target:control ratio <0.88. Using these cut-offs all 13 oligodendroglioma demonstrated 1p19q codel.
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Affiliation(s)
- P L Kong
- Genomic Medical Science, University Malaya, Faculty of Medicine and Health Sciences, Department of Pathology, Kuala Lumpur, Malaysia.
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11
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Mohd Sobri SN, Abdul Sani SF, Sabtu SN, Looi LM, Chiew SF, Pathmanathan D, Chio-Srichan S, Bradley DA. Structural Studies of Epithelial Mesenchymal Transition Breast Tissues. Sci Rep 2020; 10:1997. [PMID: 32029810 PMCID: PMC7005319 DOI: 10.1038/s41598-020-58932-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 01/13/2020] [Indexed: 11/09/2022] Open
Abstract
At the supramolecular level, the proliferation of invasive ductal carcinoma through breast tissue is beyond the range of standard histopathology identification. Using synchrotron small angle x-ray scattering (SAXS) techniques, determining nanometer scale structural changes in breast tissue has been demonstrated to allow discrimination between different tissue types. From a total of 22 patients undergoing symptomatic investigations, different category breast tissue samples were obtained in use of surgically removed tissue, including non-lesional, benign and malignant tumour. Structural components of the tissues were examined at momentum transfer values between q = 0.2 nm-1 and 1.5 nm-1. From the SAXS patterns, axial d-spacing and diffuse scattering intensity were observed to provide the greatest discrimination between the various tissue types, specifically in regard to the epithelial mesenchymal transition (EMT) structural component in malignant tissue. In non-lesional tissue the axial period of collagen is within the range 63.6-63.7 nm (formalin fixed paraffin embedded (FFPE) dewaxed) and 63.4 (formalin fixed), being 0.9 nm smaller than in EMT cancer-invaded regions. The overall intensity of scattering from cancerous regions is a degree of magnitude greater in cancer-invaded regions. Present work has found that the d-spacing of the EMT positive breast cancer tissue (FFPE (dewaxed)) is within the range 64.5-64.7 nm corresponding to the 9th and 10th order peaks. Of particular note in regard to formalin fixation of samples is that no alteration is observed to occur in the relative differences in collagen d-spacing between non-lesional and malignant tissues. This is a matter of great importance given that preserved-sample and also retrospective study of samples is greatly facilitated by formalin fixation. Present results indicate that as aids in tissue diagnosis SAXS is capable of distinguishing areas of invasion by disease as well as delivering further information at the supramolecular level.
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Affiliation(s)
- S N Mohd Sobri
- Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - S F Abdul Sani
- Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, 50603, Malaysia.
| | - Siti Norbaini Sabtu
- Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - L M Looi
- Department of Pathology, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - S F Chiew
- Department of Pathology, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - Dharini Pathmanathan
- Institute of Mathematical Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - Sirinart Chio-Srichan
- Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima, 30000, Thailand
| | - D A Bradley
- Centre for Biomedical Physics, Sunway University, Petaling Jaya, Kuala Lumpur, 46150, Malaysia
- Department of Physics, University of Surrey, Guildford, GU2 7XH, UK
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Cheah PL, Li J, Looi LM, Koh CC, Lau TP, Chang SW, Teoh KH, Mun KS, Nazarina AR. Screening for microsatellite instability in colorectal carcinoma: Practical utility of immunohistochemistry and PCR with fragment analysis in a diagnostic histopathology setting. Malays J Pathol 2019; 41:91-100. [PMID: 31427545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Since 2014, the National Comprehensive Cancer Network (NCCN) has recommended that colorectal carcinoma (CRC) be universally tested for high microsatellite instability (MSI-H) which is present in 15% of such cancers. Fidelity of resultant microsatellites during DNA replication is contingent upon an intact mismatch repair (MMR) system and lack of fidelity can result in tumourigenesis. Prior to commencing routine screening for MSI-H, we assessed two commonly used methods, immunohistochemical (IHC) determination of loss of MMR gene products viz MLH1, MSH2, MSH6 and PMS2 against PCR amplification and subsequent fragment analysis of microsatellite markers, BAT25, BAT26, D2S123, D5S346 and D17S250 (Bethesda markers) in 73 unselected primary CRC. 15.1% (11/73) were categorized as MSI-H while deficient MMR (dMMR) was detected in 16.4% (12/73). Of the dMMR, 66.7% (8/12) were classified MSI-H, while 33.3% (4/12) were microsatellite stable/low microsatellite instability (MSS/MSI-L). Of the proficient MMR (pMMR), 95.1% (58/61) were MSS/MSI-L and 4.9% (3/61) were MSI-H. The κ value of 0.639 (standard error =0.125; p = 0.000) indicated substantial agreement between detection of loss of DNA mismatch repair using immunohistochemistry and the detection of downstream microsatellite instability using PCR. After consideration of advantages and shortcomings of both methods, it is our opinion that the choice of preferred technique for MSI analysis would depend on the type of laboratory carrying out the testing.
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Affiliation(s)
- P L Cheah
- University Malaya, Faculty of Medicine, Department of Pathology, Lembah Pantai, 59100, Kuala Lumpur, Malaysia.
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13
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Marutha Muthu AK, Cheah PL, Koh CC, Chew MF, Toh YF, Looi LM. Cyclooxygenase-2 (COX2) expression in adenocarcinoma surpasses that of squamous cell carcinoma in the uterine cervix. Malays J Pathol 2017; 39:251-255. [PMID: 29279587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Over the years, adenocarcinoma (ADC), which has a worse prognosis than squamous cell carcinoma (SCC) of the cervix, has shown an increasing trend. Cyclooxygenase-2 (COX2) expression which has been associated with worse prognosis in several solid cancers was studied for its association with SCC and ADC of the cervix. 35 histologically re-confirmed SCC and 35 ADC were immunohistochemically stained for COX2 using a mouse monoclonal antibody to COX2 (1:100; Dako: Clone CX-294) on a Ventana Benchmark XT. The histoscore was computed as intensity of staining, semi-quantitated on a scale of 0-3 with 0 = negative, 1 = weak, 2 = moderate and 3 = strong staining intensity; multiplied by percentage of immunopositivity on a scale of 0-4 with 0 = <1%, 1 = 1-25%, 2 = 26-50%, 3 = 51-75% and 4 = ≥75% of immunopositive tumour cells. Histoscore 1-3/12 was considered as low and ≥4/12 as high COX2 expression. SCC affected Chinese more than Malays, while Malays had more ADC (p = 0.032). Mean age at presentation of SCC (57.5 years) was about a decade later than ADC at 47.9 years (p = 0.002). 30/35 (85.7%) of SCC and 34/35 (97.1%) of ADC expressed COX2. Histoscores of ADC (median = 4.0, IQR = 3.0-6.0) was significantly higher (p = 0.014) than those of SCC (median = 3.0, IQR = 2.0-3.0). High histoscores (≥4/12) were more frequent in ADC (55.9%) compared with SCC (26.7%) (p = 0.018), implicating COX2, either directly or indirectly, as a possible player in influencing the poorer outcome of ADC compared with SCC.
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Affiliation(s)
- A K Marutha Muthu
- University of Malaya, Faculty of Medicine, Department of Pathology, Kuala Lumpur, Malaysia.
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Burke KA, Berman S, Geyer FC, Piscuoglio S, Ng CK, Wen YH, Mannermaa A, Peterlongo P, Tondini C, Janatova M, Soo Hwang T, Ng PS, Looi LM, Chenevix-Trench G, Southey MC, Weigelt B, Foulkes W, Tischkowitz M, Reis-Filho JS. Abstract P2-03-01: Mutational landscape of breast cancers from PALB2 germline mutation carriers. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-p2-03-01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: The PALB2 gene encodes the partner and localizer of the BRCA2 protein, which participates in homologous recombination during DNA repair via an interaction with BRCA1 and BRCA2. Germline mutations in PALB2 are associated with an increased risk of breast cancer, with a cumulative risk of 35% by age 70 in female PALB2 mutant carriers. The aims of this project were to characterize the genomic landscape of PALB2 breast cancers and define the differences in the repertoire of somatic genetic alterations and mutational signatures between PALB2, BRCA1 and BRCA2 breast cancers.
Methods: Representative samples from fourteen breast cancers from patients with known PALB2 germline mutations (seven frame-shift (2 H1170fs, 3 K346fs, 1 T841fs and 1 L531fs), five truncating (3 W1038* and 2 Q775*) and two missense (W1140G and L35P)) were microdissected to ensure a tumor cell content of >70%. DNA samples from microdissected tumors and their matched normal counterparts were subjected to whole exome sequencing on an Illumina HiSeq2000 to a median depth of 118x (range 33-193x). Somatic single nucleotide variations were detected using MuTect, and small insertions and deletions were identified using Strelka and Varscan2. Using ABSOLUTE and FACETS, we investigated the presence of loss of heterozygosity (LOH) of the PALB2 wild-type allele in these tumors. In addition, the mutational signatures and large scale state transitions (LSTs) were defined. The repertoire of somatic mutations identified in PALB2 breast cancers was compared to that of breast cancers from BRCA1 (n=11) and BRCA2 (n=10) germline mutation carriers from The Cancer Genome Atlas study.
Results: PALB2 breast cancers were found to harbor a median of 80 somatic mutations (range 22-286) and one somatic mutation (range 0-13) affecting known cancer genes. Somatic loss of the PALB2 wild-type allele was found in five cases, and in three additional cases, a second PALB2 somatic mutation likely constituted the second 'hit' (two with truncating mutations, Q479* and Q61*, and one with a Q921fs frameshift mutation). Six PALB2 breast cancers displayed the BRCA mutations signature; of these, five had PALB2 bi-allelic inactivation (three LOH of the wild-type allele and two a second PALB2 somatic mutation). 71% of the samples were found to have LSTs, including all cases with a BRCA mutational signature. A significant association between PALB2 bi-allelic inactivation and concurrent BRCA signature and high LST was observed (p=0.015). Breast cancers from PALB2 mutation carriers had fewer somatic TP53 mutations than BRCA1 breast cancers (3/14, 21% vs 9/11, 82%, p=0.004), but no difference in the repertoire of somatic mutations compared to that of BRCA2 breast cancers.
Conclusions: PALB2 breast cancers were found to harbor pathogenic mutations in driver genes, including TP53, PIK3CA, NF1 and NCOR1, however lacked highly recurrent somatic mutations. Unlike BRCA1/2 breast cancers, the majority of breast cancers from PALB2 germline mutation carriers lacked LOH of the PALB2 wild-type allele. Importantly, however, an association between PALB2 bi-allelic inactivation and the BRCA mutational signature and LSTs was observed, providing additional evidence for a homologous recombination-deficient phenotype at least in a subset of PALB2 cancers.
Citation Format: Burke KA, Berman S, Geyer FC, Piscuoglio S, Ng CK, Wen YH, Mannermaa A, Peterlongo P, Tondini C, Janatova M, Soo Hwang T, Ng P-S, Looi LM, Chenevix-Trench G, Southey MC, Weigelt B, Foulkes W, Tischkowitz M, Reis-Filho JS, PALB2 Interest Group. Mutational landscape of breast cancers from PALB2 germline mutation carriers [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-03-01.
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Affiliation(s)
- KA Burke
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - S Berman
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - FC Geyer
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - S Piscuoglio
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - CK Ng
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - YH Wen
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - A Mannermaa
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - P Peterlongo
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - C Tondini
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - M Janatova
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - T Soo Hwang
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - P-S Ng
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - LM Looi
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - G Chenevix-Trench
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - MC Southey
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - B Weigelt
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - W Foulkes
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - M Tischkowitz
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
| | - JS Reis-Filho
- Memorial Sloan Kettering Cancer Center, New York, NY; University of Eastern Finland, Kuopio, Finland; IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy; Ospedale Papa Giovanni XXIII, Bergamo, Italy; Charles University, Prague, Czech Republic; Cancer Research Malaysia, Selangor, Malaysia; University of Malaya, Kuala Lumpur, Malaysia; University of Queensland, Brisbane, Australia; University of Melbourne, Melbourne, Australia; McGill University, Montreal, Canada; University of Cambridge, Cambridge, United Kingdom
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Toh YF, Cheah PL, Looi LM, Teoh KH, Tan PH. ERRATUM: Phyllodes tumours of the breast: retrospective analysis of a University Hospital's experience. Malays J Pathol 2016; 38:175. [PMID: 27568677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
No abstract available.
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Affiliation(s)
- Y F Toh
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Malaysia.
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Subramaniam S, Bhoo-Pathy N, Taib NA, Tan GH, See MH, Jamaris S, Ho GF, Looi LM, Yip CH. Breast Cancer Outcomes as Defined by the Estrogen Receptor, Progesterone Receptor, and Human Growth Factor Receptor-2 in a Multi-ethnic Asian Country. World J Surg 2016; 39:2450-8. [PMID: 26138872 DOI: 10.1007/s00268-015-3133-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Breast cancer can be divided into four subtypes based on the expressions of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor-2 (HER2). Each subtype has different clinicopathological features and outcomes. OBJECTIVE To compare the clinicopathological features and survival of ER and/or PR positive HER2 negative (ER+PR+HER2-, ER+PR-HER2- or ER-PR+HER2-), ER and/or PR positive HER2 positive (ER+PR+HER2+, ER+PR-HER2+ or ER-PR+HER2+), ER negative PR negative HER2 positive (ER-PR-HER2+), and ER negative PR negative HER2 negative (ER-PR-HER2-) subtypes. METHODS 1957 patients with Stage 1-3 breast carcinoma diagnosed between Jan 2005 and Dec 2011 were categorized into the four subtypes. The clinicopathological features between the subtypes were compared using χ (2) test. Kaplan-Meier analysis was performed to estimate 5-year overall survival. Multivariate Cox regression was used to determine the association between subtypes and mortality adjusted for age, ethnicity, stage, pathological features, and treatment. RESULTS ER-PR-HER2+ and ER-PR-HER2- subtypes were associated with younger age, larger tumors, and higher grade. There was no difference in the 5-year survival of the ER-PR-HER2+ and ER-PR-HER2- subtypes (75.1 and 74.4 %, respectively) and survival was poorer than in the ER and/or PR positive HER2 negative and ER and/or PR positive HER2 positive subtypes (87.1 and 83.1 %, respectively). Only 9.5 % of women with HER2 positive breast cancer had access to trastuzumab. CONCLUSION In a low resource setting with limited access to trastuzumab, there is no difference in survival between the ER-PR-HER2+ and ER-PR-HER2- subtypes of breast cancer.
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Affiliation(s)
- S Subramaniam
- National Clinical Research Centre, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia,
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Toh YF, Cheah PL, Looi LM, Teoh KH, Tan PH. Phyllodes tumours of the breast: retrospective analysis of a University Hospital's experience. Malays J Pathol 2016; 38:19-24. [PMID: 27126660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Taking cognizance of the purported variation of phyllodes tumours in Asians compared with Western populations, this study looked at phyllodes tumours of the breast diagnosed at the Department of Pathology, University of Malaya Medical Centre over an 8-year period with regards to patient profiles, tumour parameters, treatment offered and outcome. Sixty-four new cases of phyllodes tumour were diagnosed during the period, however only 30 (21 benign, 4 borderline and 5 malignant) finally qualified for entry into the study. These were followed-up for 4-102 months (average = 41.7 months). Thirteen cases (8 benign, 3 borderline, 2 malignant) were Chinese, 9 (all benign) Malay, 7 (4 benign, 1 borderline, 2 malignant) Indian and 1 (malignant) Indonesian. Prevalence of benign versus combined borderline and malignant phyllodes showed a marginally significant difference (p=0.049) between the Malays and Chinese. Patients' ages ranged from 21-70 years with a mean of 44.9 years with no significant difference in age between benign, borderline or malignant phyllodes tumours. Except for benign phyllodes tumours (mean size = 5.8 cm) being significantly smaller at presentation compared with borderline (mean size = 12.5 cm) and malignant (mean size = 15.8 cm) (p<0.05) tumours, history of previous pregnancy, breast feeding, hormonal contraception and tumour laterality did not differ between the three categories. Family history of breast cancer was noted in 2 cases of benign phyllodes. Local excision was performed in 17 benign, 2 borderline and 3 malignant tumours and mastectomy in 4 benign, 2 borderline and 2 malignant tumours. Surgical clearance was not properly recorded in 10 benign phyllodes tumours. Six benign and all 4 borderline and 5 malignant tumours had clearances of <10 mm. Two benign tumours recurred locally at 15 and 49 months after local excision, however information regarding surgical clearance was not available in both cases. One patient with a malignant tumour developed a radiologically-diagnosed lung nodule 26 months after mastectomy, was given a course of radiotherapy and remained well 8-months following identification of the lung nodule.
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Affiliation(s)
- Y F Toh
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Malaysia.
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Cheah PL, Koh CC, Nazarina AR, Teoh KH, Looi LM. Correlation of p16INK4a immunoexpression and human papillomavirus (HPV) detected by in-situ hybridization in cervical squamous neoplasia. Malays J Pathol 2016; 38:33-38. [PMID: 27126662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Persistence and eventual integration of high-risk HPV (hrHPV) into the cervical cell is crucial to the progression of cervical neoplasia and it would be beneficial to morphologically identify this transformation in routine surgical pathology practice. Increased p16(INK4a) (p16) expression is a downstream event following HPV E7 binding to pRB. A study was conducted to assess the correlation between hrHPV detection using a commercial in-situ hybridization assay (Ventana INFORM HPV ISH) and p16 immunoexpression (CINtec Histology Kit) in cervical squamous intraepithelial lesions and squamous carcinoma. 27 formalin-fixed, paraffin-embedded cervical low-grade squamous intraepithelial lesions (LSIL), 21 high-grade squamous intraepithelial lesions (HSIL) and 51 squamous carcinoma (SCC) were interrogated. hrHPV was significantly more frequent in HSIL (76.2%) and SCC (88.2%) compared to LSIL(37.0%). p16 expression was similarly more frequent in HSIL (95.2%) and SCC (90.2%) compared to LSIL(3.7%). That the rates of hrHPV when compared with p16 expression were almost equivalent in HSIL and SCC while p16 was expressed in only 1 of the 10 LSIL with hrHPV, are expected considering the likelihood that transformation has occurred in HSIL and SCC but does not occur in majority of LSIL.
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Affiliation(s)
- P L Cheah
- University of Malaya, Faculty of Medicine, Department of Pathology, 50603 Kuala Lumpur, Malaysia.
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Looi LM, Wong LX, Koh CC. Response: Scientific misconduct encountered by APAME journals: insight? Malays J Pathol 2016; 38:73. [PMID: 27126670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- L M Looi
- University of Malaya, Faculty of Medicine, Department of Pathology, Kuala Lumpur, Malaysia
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Elbashier SHA, Nazarina AR, Looi LM. Cytokeratin immunoreactivity in Ewing sarcoma/ primitive neuroectodermal tumour. Malays J Pathol 2013; 35:139-145. [PMID: 24362477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Ewing sarcoma (ES)/ primitive neuroectodermal tumour (PNET) is an aggressive malignant neoplasm affecting mainly children and young adults. The tumour is included with other primitive neoplasms under the category of small round cell tumour. Cytokeratin expression in ES/PNET has been described in sporadic case reports as well as a few systemic series. We studied this feature in Malaysian patients diagnosed in University Malaya Medical Centre on the basis of typical morphology and immunohistochemical assays. Immunohistochemical staining for AE1/AE3 and MNF116 were performed in 43 cases. Cytokeratin was expressed in 17 cases (39.5%) in focal, intermediate or diffuse patterns. There was no significant association between cytokeratin immunoreactivity and the following parameters: patient age, sex, skeletal and extraskeletal primary location as well as primary, metastastic or recurrent tumours or chemotherapy treatment. A significant association between cytokeratin and neuron specific enolase (NSE) expression was demonstrated. Our study supports evidence of epithelial differentiation in ES/PNET and emphasizes that the expression of cytokeratin does not exclude ES/PNET in the differential diagnosis of small round cell tumours.
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Affiliation(s)
- S H A Elbashier
- University Malaya, Faculty of Medicine, Pathology Department, Jalan Universiti, 50603 Kuala Lumpur, Malaysia
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Looi LM. Food for thought: chocolate. Malays J Pathol 2013; 35:109. [PMID: 24362473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Affiliation(s)
- L M Looi
- University of Malaya, Faculty of Medicine, Department of Pathology, Jalan Universiti, 50603 Kuala Lumpur, Malaysia
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Looi LM, Lapeña JF. The kuala lumpur declaration - a misattributed authorship? Med J Malaysia 2013; 68:91-92. [PMID: 23466781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Affiliation(s)
- L M Looi
- University of Malaya, Department of Pathology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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Lee WS, Chai PF, Boey CM, Looi LM. Aetiology and outcome of neonatal cholestasis in Malaysia. Singapore Med J 2010; 51:434-439. [PMID: 20593150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
INTRODUCTION Little is known about the epidemiology, causes and outcomes of neonatal cholestasis in the Asian population beyond Japan and Taiwan. METHODS This was a prospective, observational study on patients with neonatal cholestasis who were referred to the University of Malaya Medical Centre, Malaysia, between November 1996 and May 2004. RESULTS Biliary atresia (BA) (29 percent) and idiopathic neonatal hepatitis (38 percent) were the two commonest causes of neonatal cholestasis (n is 146) that were referred. Out of the 39 patients (27 percent of the total) who died at the time of review, 35 succumbed to end-stage liver disease. Three of the four patients (three BA, one progressive familial intrahepatic cholestasis [PFIC]) who had a living-related liver transplant (LT) died after the surgery (two BA, one PFIC). Six (four percent) of the remaining 107 survivors had liver cirrhosis. The overall four-year survival rates for patients with native liver and LT as well as those with native liver alone for all cases of neonatal cholestasis were 72 percent and 73 percent, respectively, while the respective survival rates for BA were 38 percent and 36 percent. CONCLUSION BA and idiopathic neonatal hepatitis are important causes of neonatal cholestasis in Malaysian infants. In Malaysia, the survival rate of patients with neonatal cholestasis, especially BA, is adversely affected by the lack of a timely LT.
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Affiliation(s)
- W S Lee
- Department of Paediatrics, University of Malaya Medical Centre, Kuala Lumpur 59100, Malaysia.
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Goh JH, Saravanan S, Ng WM, Looi LM, Ali R. Localised Pigmented Villonodular Synovitis Presenting As Anterior Knee Pain. Malays Orthop J 2010. [DOI: 10.5704/moj.1003.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Looi LM. Nurturing young writers: sustaining quality, not quantity. Singapore Med J 2009; 50:1044-1047. [PMID: 19960155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The exponential growth in scientific journals and advent of the electronic era have led to such information overload that the sustainability of credible and quality publications is more urgent than ever. Editors and academics who commit themselves to nurturing young writers need to reaffirm their focus on quality rather than quantity of papers. Bearing in mind that publications should firstly be founded on good science, there are several approaches in helping the uninitiated develop and hone writing skills. Academic journals faithfully publish instructions to guide potential authors on the preparation and submission of manuscripts. For those with a gift for writing, this may suffice to start them soaring in their writing career. Others find the hands-on approach of writing workshops more effective in clarifying the rules of the writing game and dispelling the fear of writing. Workshops are good at demonstrating the basics, but the forging of a good writer is a long process in which a mentor can play an invaluable role. A nurturing mentor-mentee relationship should not be a stifling one, but one that leads, grows and finally liberates an independent writer. It is inevitable that the nature of scientific publications will change over time. Nonetheless, the sustainability of quality journals will remain linked to the continual generation of writers who uphold scientific truth and good writing values.
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Lee WS, Chai PF, Looi LM. Progressive familial intrahepatic cholestasis in Malaysian patients--a report of five cases. Med J Malaysia 2009; 64:216-219. [PMID: 20527271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Progressive familial intrahepatic cholestasis (PFIC) is characterized by early onset cholestasis, progressive liver cirrhosis, pruritus, poor growth and inexorable progression to liver cirrhosis in early childhood. The serum level of gamma-glutamyl transferase is low or normal, which is discordant with severe cholestasis. Five Malaysian patients with PFIC, who all had typical features of PFIC with early onset of severe and progressive cholestasis, pruritus, cirrhosis and liver failure, were described. Three patients died as a result of the disease, while another one died due to post-liver transplant complication. The only survivor has compensated liver cirrhosis. Patients with severe cholestasis but has spuriously low yGT should be suspected of having PFIC. Liver transplant, which is life-saving in a majority of patients with PFIC, should be considered in all patients with PFIC.
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Affiliation(s)
- W S Lee
- Department of Paediatrics, University of Malaya Medical Centre, 59100 Kuala Lumpur, Malaysia.
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Tan EL, Looi LM, Sam CK. Evaluation of plasma Epstein-Barr virus DNA load as a prognostic marker for nasopharyngeal carcinoma. Singapore Med J 2006; 47:803-7. [PMID: 16924363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
INTRODUCTION Nasopharyngeal carcinoma (NPC) is an important cancer in Malaysia and is one of the major causes of cancer mortality in this country. This study evaluates the diagnostic and prognostic values in the quantitative relationship between the cell-free Epstein-Barr virus (EBV) deoxyribonucleic acid (DNA) load and the tumour burden. METHODS Blood plasma from 18 untreated NPC patients, 20 NPC patients who had been treated with radiotherapy, and 12 healthy individuals were evaluated. EBV copy number was determined following DNA extraction using real-time quantitative polymerase chain reaction. RESULTS The cell-free EBV DNA load was shown to be proportionately related to the presence of malignant disease. While the EBV copy number in untreated NPC patients had a median of 2,043 copies/ml, viral load in plasma of healthy controls was significantly lower (median of 0 copy/ml). A significant decrease in EBV load was observed in patients who had undergone radiotherapy while a high viral load indicated in one patient correlated to tumour relapse and presence of distant metastasis upon clinical investigation. CONCLUSION The blood plasma EBV DNA load was shown to be proportionately related to the presence of malignant disease. This preliminary study underscores the prognostic value of cell-free EBV DNA quantification.
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Affiliation(s)
- E L Tan
- Department of Pharmacy and Health Sciences, International Medical University, Plaza Komanwel, Bukit Jalil, Kuala Lumpur 57000, Malaysia.
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Looi LM, Zubaidah Z, Cheah PL, Cheong SK, Gudum HR, Iekhsan O, Ikram SI, Jamal R, Mak JW, Othman NH, Puteri JN, Rosline H, Sabariah AR, Seow HF, Sharifah NA. Research on cancer diagnosis in Malaysia: current status. Malays J Pathol 2005; 26:13-27. [PMID: 16190103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 09/28/2022]
Abstract
Cancer is a major morbidity and mortality concern in Malaysia. Based on National Cancer Registry data, the Malaysian population is estimated to bear a cancer burden of about 40,000 new cases per year, and a cumulative lifetime risk of about 1:4. Cancer research in Malaysia has to consider needs relevant to our population, and resources constraints. Hence, funding bodies prioritise cancers of high prevalence, unique to our community and posing specific clinical problems. Cancer diagnosis is crucial to cancer management. While cancer diagnosis research largely aims at improvements in diagnostic information towards more appropriate therapy, it also impacts upon policy development and other areas of cancer management. The scope of cancer diagnosis upon which this paper is based, and their possible impact on other R&D areas, has been broadly categorized into: (1) identification of aetiological agents and their linkages to the development of precancer and cancer (impact on policy development, cancer prevention and treatment), (2) cancer biology and pathogenesis (impact on cancer prevention, treatment strategies and product development), (3) improvements in accuracy, sensitivity and specificity in cancer detection, monitoring and classification (impact on technology development) and (4) prognostic and predictive parameters (impact on treatment strategies). This paper is based on data collected by the Working Group on Cancer Diagnosis Research for the First National Conference on Cancer Research Coordination in April 2004. Data was collated from the databases of Institutions/Universities where the authors are employed, the Ministry of Science, Technology and Innovation (MOSTI) and targeted survey feedback from key cancer researchers. Under the 7th Malaysia Plan, 76 cancer projects were funded through the Intensified Research in Priority Areas (IRPA) scheme of MOSTI, amounting to almost RM15 million of grant money. 47(61.8%) of these projects were substantially in cancer diagnosis, accounting for 65.6% (RM 9.7 million) of cancer project funds. The 8th Malaysia Plan saw a change in research strategy. The IRPA agency fielded several top-down projects which encouraged a multicentre and multidisciplinary approach. This resulted in larger funding per project i.e. RM32 million for 49 projects. There was also a surge of interest in drug development and natural products. Because of this shift in direction, cancer diagnosis projects constituted only 51% of IRPA-funded cancer projects. Nonetheless funding for cancer diagnosis research has exceeded that of the 7th Malaysia Plan, being RM12.5 million by March 2004. The majority of such research is carried out at the Universities, engaging a large number of young scientists and postgraduate students (51 MSc and 21 PhD). A lot of research findings presented at scientific meetings have not yet been published and there is a glaring shortage of patents and commercialization of research findings (such as creation of test kits). Because diagnosis is very much a part of clinical practice, many researchers felt satisfied and confident that their work will be translated into practice and will significantly improve diagnostic services in Malaysia. National guidelines and consensus development on at least three malignancies i.e. breast cancer, oral cancer and lymphoma, have substantial basis in local R&D work. Problems encountered in research included (1) insufficient funding to realize research objectives, (2) lack of local expertise (most research assistants are inexperienced BSc graduates with no or minimal research experience), (3) inadequate technical support from vendors during equipment failure, (4) inexperienced Institutional development units to assist in product development, (5) lack of venture capital for commercialization of findings, and (6) inadequate incentives to undertake research. Researchers pointed out that plans to promote research should include the establishment of (1) regional and national cancer tissue banks, (2) a National Cancer Research Institute, (3) a dedicated cancer research fund, (4) a registry of cancer researchers, (5) national research coordinators, (6) improved coverage by the National Cancer Registry, (7) more international collaboration, (8) a better career structure for researchers, (9) improved Institutional support for product realization, and (10) better recognition for cancer researchers.
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Affiliation(s)
- L M Looi
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Shekhar K, Lye MS, Norlijah O, Ong F, Looi LM, Khuzaiah R, Marzuki I, Hussein I, Wong SL, Mohan J, Sinniah M, Abu Bakar S. Deaths in children during an outbreak of hand, foot and mouth disease in Peninsular Malaysia--clinical and pathological characteristics. Med J Malaysia 2005; 60:297-304. [PMID: 16379183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
From July through December 1997, 11 previously healthy children in Peninsular Malaysia succumbed to an illness clinically characterised by an acute severe refractory left-ventricular failure, following a brief prodromal illness, in the midst of an outbreak of hand, foot and mouth disease (HFMD), similar to the reported experience in Sarawak and Taiwan. Retrospective reviews of the clinical features and results of laboratory, pathological and virological investigations of cases were conducted. The median age of the 11 case-patients was 31 months (range, 13 to 49 months); 6 were males. A brief prodromal illness of 3 days (range, 2 to 5 days) was characterised by fever (axillary temperature > 38 degrees C) (100%), oral ulcers (72%), extremity rashes (45%) and significant vomiting (55%). Upon hospitalisation, 7 of 11 case-patients had features suggestive of cardiogenic shock, while 4 of 11 case-patients developed shock during hospitalisation as evidenced by marked sustained tachycardia (heart rate > or = 180 beats per minute), poor peripheral pulses and peripheral perfusion, mottled extremities, pulmonary oedema (haemorrhagic pulmonary secretions in 8 of 11 cases during tracheal intubation, often precipitated by conservative crystalloid boluses, and radiographic evidence of acute pulmonary oedema in 5 of 7 cases) and markedly impaired left ventricular function on echocardiographic examination (7 of 7 cases). Three of 4 case-patients had aseptic meningitis while one case-patient also had an acute flaccid paraparesis. Despite supportive therapy, death occurred within a median of 13.4 hours following hospitalization. Post-mortem findings (all 8 specimens examined) consistently demonstrated brain-stem encephalitis with foci of neuronal necrosis and micro-abscesses. None of the 11 specimens examined revealed histological evidence of myocarditis. Enterovirus 71 (EV71) was detected in 10 of 11 case-patients, many (7) from various sterile tissue sites (5 from central nervous tissues). No other viruses were isolated or identified. Clinical features and pathological studies closely paralleled the reported experience in Sarawak and Taiwan. The uniform necropsy findings of necrotizing brain-stem encephalitis coupled with essentially normal myocardial histology, in concert with the concurrent and consistent detection of EV71 points to a primary EV71 encephalitis; as yet unclear neurogenic mechanisms may account for the cardiovascular manifestations.
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Looi LM. Hepatobiliary practical: how to get the best out of a liver biopsy. Med J Malaysia 2005; 60 Suppl B:144-5. [PMID: 16108199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The liver biopsy has a unique place in the investigation of liver disease because the concepts and classification of liver disease are rooted in morphology. Today, the use of the liver biopsy has extended beyond that of diagnosis, to the assessment of disease progression, response to therapy and transplant rejection. To get the best out of the liver biopsy, it is necessary to appreciate the usefulness and limitations of the biopsy specimen. Aspects to consider include: (1) minimizing sampling errors, and appreciating that the changes in the biopsy may not be representative of the primary pathology, (2) good laboratory quality practices to avoid processing artifacts, which may render a biopsy undiagnosable, (3) the appropriate use of special stains and other laboratory techniques, (4) adoption of a systematic and algorithmic approach in the microscopic examination of the biopsy, and (5) good clinicopathological correlation.
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Affiliation(s)
- L M Looi
- Department of Pathology, University Malaya Medical Centre, Kuala Lumpur, Malaysia
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Abstract
Cryptococcus neoformans is a yeast like fungus, which is commonly found in bird droppings, especially pigeons. Most cases of cryptococcal infections occur in immunocompromised patients or in those who are on long term immunosuppressant therapies. Cryptococcal infection usually presents as a meningoencephalitis or a pulmonary infection. Skin, bone and genital infections are very rare. We report the second case of vaginal cryptococcossis to be reported in English literature and the first to be imaged with CT and MRI.
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Affiliation(s)
- S Ranganathan
- Department of Radiology, University of Malaya Medical Centre, Lumpar, Malaysia
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Amalourde A, Vinayaga P, Naveed N, Jamal A, Looi LM, Sengupta S. A rare case of chondrosarcoma of the clavicle. Med J Malaysia 2004; 59 Suppl F:60-2. [PMID: 15941166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Although all types of tumour and tumour-like conditions have been described to occur in the clavicle, they only contribute to less then 0.5% of all skeletal tumours. The incidence of primary chondrosarcoma of the clavicle is extremely rare. To our knowledge it has not been reported in Malaysia. We would like to highlight the possibility of chondrosarcoma as a differential diagnosis for a clavicular lesion.
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Gan WH, Thye YL, Chang SH, Chua CB, Looi LM, Tan SY. Posttransplant lymphoproliferative disease masquerading as postbiopsy hematoma. Transplant Proc 2004; 36:2148-9. [PMID: 15518779 DOI: 10.1016/j.transproceed.2004.08.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- W H Gan
- Renal Unit, University Malaya Medical Centre, Kuala Lumpur, Malaysia
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Abstract
Vulvar ulceration is a rare manifestation of histiocytosis X. A 13-year-old girl had a nonhealing vulvar ulcer for 1 year. She had been in remission from histiocytosis X and the ulcer was not recognised as a sign of disease recurrence until tissue biopsy was obtained for histopathological and immunohistochemical studies. This article stresses the importance of establishing an accurate diagnosis when chronic vulvar ulcers are encountered and reviews the literature on this uncommon presentation of histiocytosis X.
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Affiliation(s)
- K K Wong
- Department of Obstetrics and Gynaecology, Faculty of Medicine, University of Malaya, Kuala Lumpur
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Cheah PL, Looi LM, Nazarina AR, Goh KL, Rosmawati M, Vijeyasingam R. Histopathological landmarks of hepatocellular carcinoma in Malaysians. Malays J Pathol 2003; 25:37-43. [PMID: 16196376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A study was conducted at the Department of Pathology, University of Malaya Medical Centre, Kuala Lumpur into the histological type (WHO classification), grade (modified Edmondson and Steiner's grading system), mitotic rate, bile production, hyaline globule and Mallory hyaline formation of 52 cases of hepatocellular carcinoma (HCC) diagnosed during a 13-year period between 1st January 1990 to 31st December 2002. In addition, associated cirrhosis, dysplasia (large liver cell dysplasia: LLCD and small liver cell dysplasia: SLCD) and microvascular permeation were also looked for whenever the situation permitted. The patients' ages ranged from 21-years to 85-years (mean = 58.7 years) with a predilection for males and Chinese. Histologically, majority (73.1%) of the tumours demonstrated a trabecular pattern of growth. The bulk (73%) of the tumours were either of grade II or III differentiation. Mitotic activity ranged between 0-100/10 high power fields (hpf) with a mean of 22.2/10 hpf. Bile was noted in 25%, hyaline globules 17.3% and Mallory bodies in one case. Concomitant cirrhosis was present in 73.5%. 73.5% of the cases had associated LLCD. 5 with LLCD also showed SLCD. Microvascular permeation was shown in 76.2% of cases. On comparison with findings from other studies, no major difference seems to exist between the histological characteristics of our HCC cases and that of other populations.
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Affiliation(s)
- P L Cheah
- Department of Pathology, University of Malaya Medical Centre, Kuala Lumpur, Malaysia
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Munchar MJJ, Sharifah NA, Jamal R, Looi LM. CD44s expression correlated with the International Neuroblastoma Pathology Classification (Shimada system) for neuroblastic tumours. Pathology 2003; 35:125-9. [PMID: 12745459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
AIM CD44 is a cell adhesion molecule that plays an important role in the cascade of metastasis and progression of human malignant tumours. A large family of variants or isoforms, generated by alternative splicing of a single gene, has been reported to be involved in the malignant process by conferring metastatic potential to non-metastatic cells. The objective of this study was to compare the expression of CD44 standard molecule with the International Neuroblastoma Pathology Classification (INPC) for neuroblastic tumours, a histological grading system based on the Shimada system for predicting the clinical outcome in neuroblastic tumours. METHODS Paraffin blocks of primary neuroblastic tumour were graded according to the INPC system into favourable and unfavourable histological types. Tumour tissues were then analysed with immunostaining using monoclonal antibodies against the CD44 epitope. RESULTS In this retrospective study, 32 cases of primary neuroblastic tumour were collected. Based on the INPC system, 13 cases (40.6%) had a favourable histology while 19 cases (59.4%) were of unfavourable histology. CD44 standard (CD44s) expression was detected in 69.2% of neuroblastic tumours with favourable histological type while 89.5% of tumours with unfavourable histological type did not express CD44s staining. Statistically, there was significant correlation between morphological grading of neuroblastic tumours based on the INPC and the presence of CD44 staining (Fisher's exact test, P<0.05). CONCLUSION This study shows that there is a significant correlation between CD44s expression and tumour histology based on the INPC in which CD44s non-expression is correlated with an unfavourable histological type and the expression of CD44s with a favourable type. Therefore, the analysis of CD44s expression should be recommended as an additional biological marker in the initial routine staging of the disease.
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Affiliation(s)
- M J Julia Munchar
- Department of Pathology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, 56000 Kuala Lumpur, Malaysia.
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Chow SK, Looi LM, Loh CS, Yeap SS. Cyclophosphamide-induced transitional cell carcinoma of bladder in lupus nephritis. Intern Med J 2002; 32:114-6. [PMID: 11885838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Affiliation(s)
- S K Chow
- Department of Medicine, Faculty of Medicine, University Malaya Medical Centre, Kuala Lumpur, Malaysia.
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Cheah PL, Looi LM, Ng MH, Sivanesaratnam V. Telomerase activation and human papillomavirus infection in invasive uterine cervical carcinoma in a set of Malaysian patients. J Clin Pathol 2002; 55:22-6. [PMID: 11825919 PMCID: PMC1769559 DOI: 10.1136/jcp.55.1.22] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
AIM Telomerase activity was studied in invasive uterine cervical carcinoma to assess whether it was activated during cervical malignant transformation and to look for a possible association with human papillomavirus (HPV) infection in a set of Malaysian patients. METHODS Histologically confirmed invasive cervical carcinoma and benign cervices were assayed for telomerase activity using a commercial telomerase polymerase chain reaction (PCR) enzyme linked immunosorbent assay kit. The same cases were subjected to PCR detection of HPV using type specific (HPV types 6b, 11, 16, and 18) followed by L1 open reading frame (ORF) consensus primers. RESULTS HPV was detected in 18 (13 HPV-16, one HPV-6b, four only L1 ORF) of 20 invasive cervical carcinoma and one (only L1 ORF) of 19 benign cervices. Raised telomerase activity (A(450 nm) > 0.215) was detected in 11 cervical carcinomas, with A(450 nm) ranging between 0.238 and 21.790 (mean, 3.952) in positive squamous carcinomas, whereas A(450 nm) was only 0.222 in the one positive adenosquamous carcinoma. Five of 11 cervical carcinomas in stage I, three of six in stage II, both in stage III, and the only case in stage IV showed telomerase activation. Increased telomerase activity was noted in five of the 12 lymph node negative, five of the seven lymph node status unknown cases, and the one case with presumed lymph node metastasis. Ten of 18 HPV positive and one of two HPV negative cervical carcinomas showed telomerase upregulation. CONCLUSIONS Telomerase is activated in invasive cervical carcinoma. Although larger studies are needed, there seems to be no clear association between telomerase upregulation and HPV status, although there is a suggestion of increased telomerase activity in squamous carcinomas and late stage disease.
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Affiliation(s)
- P L Cheah
- Department of Pathology, University of Malaya Medical Centre, 50603 Kuala Lumpur, Malaysia.
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Ariffin H, Teh KH, Looi LM, Ariffin WA, Lin HP. Infantile myofibromatosis. Med J Malaysia 2001; 56:497-9. [PMID: 12014771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Infantile myofibromatosis (IMF) is a rare tumour with a wide spectrum of disease activity ranging from a solitary cutaneous nodule through to a multicentric form with widespread visceral involvement. It is characterised by its unique ability to spontaneously regress and has a typical histological appearance of actin-positive fibroblasts arranged in whorls or fascicles and vessels in a pericytomatous pattern. A male infant with multiple lesions involving the subcutaneous tissue and bone from birth is described and followed-up for two years. Treatment of IMF is dependent on the location of the tumour/s with surgery or chemotherapy reserved for rapidly progressive or symptomatic disease. However, due to the low rate of recurrence and the possibility of spontaneous tumoral regression, therapeutic abstention, as practised in our patient, is justified.
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Affiliation(s)
- H Ariffin
- Department of Paediatrics, University of Malaya Medical Centre, Kuala Lumpur
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Zheng WQ, Looi LM, Cheah PL. A comparison of the patterns of laminin expression in fibroadenoma, fibrocystic diseases, pre-invasive and invasive ductal breast carcinoma. Pathology 2001; 33:303-6. [PMID: 11523929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The basement membrane (BM), of which laminin is a major glycoprotein component, is an important barrier to tumour cells which must be breeched before metastatic spread can occur. We have compared the pattern of laminin expression in a range of benign and malignant breast lesions to better understand the process of tumour progression. A total of 162 cases of breast samples, comprising 18 fibroadenomas, 22 cases of fibrocystic disease, 96 cases of invasive ductal carcinoma and 26 carcinomas with intraductal components, were evaluated for laminin expression by a standard immunoperoxidase method on formalin-fixed, paraffin-embedded histological sections, using a commercial antibody against human laminin. The pattern of laminin expression was charted as follows: Type I, > 70% of BM complete/continuous; Type II, > 70% of BM moderately disrupted; Type III, > 70% of BM completely disrupted. The Type I pattern was observed in all cases of fibroadenoma and fibrocystic diseases, and in 77% of intraductal carcinoma components. Various patterns of BM disruption were observed in invasive ductal carcinoma. Severity of BM disruption correlated with histological grade of the carcinomas (P < 0.001). Small-sized tumours, those without lymphatic invasion and lymph node-negative tumours showed more complete patterns of laminin expression. The current study suggests that tumour cells with high histological grade possess an enhanced capacity to disrupt the basement membrane, an important step in the metastatic process. The detection of BM disruption by immunohistochemical staining for laminin is technically easy and may be usefully applied for the differentiation of in situ and microinvasive carcinoma.
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MESH Headings
- Basement Membrane/chemistry
- Basement Membrane/metabolism
- Basement Membrane/pathology
- Breast Neoplasms/chemistry
- Breast Neoplasms/metabolism
- Breast Neoplasms/pathology
- Carcinoma, Ductal, Breast/chemistry
- Carcinoma, Ductal, Breast/metabolism
- Carcinoma, Ductal, Breast/secondary
- Carcinoma, Intraductal, Noninfiltrating/metabolism
- Carcinoma, Intraductal, Noninfiltrating/pathology
- Female
- Fibroadenoma/chemistry
- Fibroadenoma/metabolism
- Fibroadenoma/pathology
- Fibrocystic Breast Disease/chemistry
- Fibrocystic Breast Disease/metabolism
- Fibrocystic Breast Disease/pathology
- Humans
- Immunoenzyme Techniques
- Laminin/analysis
- Laminin/biosynthesis
- Middle Aged
- Neoplasm Staging
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Affiliation(s)
- W Q Zheng
- Department of Pathology, Changhai Hospital, Second Military Medical University, Shanghai, China.
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Looi LM, Azura WW, Cheah PL, Ng MH. pS2 expression in infiltrating ductal carcinoma of the breast correlates with oestrogen receptor positivity but not with histological grade and lymph node status. Pathology 2001; 33:283-6. [PMID: 11523925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
This investigation was carried out to gain insight into the prevalence of pS2 expression in invasive ductal breast carcinoma in the Malaysian population and its correlation with oestrogen receptor (ER) protein expression and tumour aggressiveness. Seventy consecutive infiltrating ductal breast carcinomas treated with mastectomy and axillary lymph node clearance were investigated, using the standard avidin-biotin complex immunoperoxidase method with microwave antigen retrieval and commercial monoclonal antibodies (Dako), for expression of pS2 and human ER. This was correlated against histological grade (modified Bloom and Richardson) and the presence of axillary lymph node metastasis of these carcinomas. Four (5.7%) were grade 1, 40 (57.1%) grade 2 and 26 (37.1%) grade 3 tumours. A total of 45 (64%) showed histological evidence of axillary lymph node metastasis. Forty (57%) were ER-positive, while 31 (44%) were pS2-positive. There was a statistically significant correlation between pS2 and ER expressions (chi2-test with Yates correction: P<0.005). There was no correlation between pS2 expression and histological grade (P>0.1) and the presence of lymph node metastasis (P>0.1). Our findings support the views that pS2 may be a co-marker of endocrine responsiveness in invasive breast cancer and that it does not influence breast cancer biology in terms of potential for metastatic spread.
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Affiliation(s)
- L M Looi
- Department of Pathology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
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Ong BB, Looi LM. Medico-legal aspects of histopathology practice. Malays J Pathol 2001; 23:1-7. [PMID: 16329541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Medico-legal problems experienced by histopathologists differ from those of other clinicians as they are rarely in direct contact with patients. Nevertheless, the pathologist owes a duty of care to the patient and is liable for medical negligence. In the absence of local guidelines, it is prudent to follow guidelines published by learned Colleges elsewhere. This is also true when delegating duties to non-pathologists, technical and other support staff. Errors in diagnosis and documentation pose the most common problems in histopathology. In this, liability also depends on many factors including the provision of adequate clinical information by clinicians and competence of laboratory staff. Clinicopathological discussions, participation in quality assurance programmes and adherence to standard operating procedures are important audit activities to minimize and detect errors as well as prevent grievous outcome to patients. Issues also arise over the retention of specimens and reports. In general, wet, formalin-fixed tissues should be kept until histopathological assessment is finalized and preferably after clinicopathological sessions, and even longer if there is potential litigation. Reports should be archival. Paraffin blocks should be kept for at least the lifetime of the patient, and histology slides for at least 10 years, to facilitate review and reassessment. Despite adverse publicity in the foreign press over the use of human organs and tissues for research and education, it is accepted that processed tissues can be used for research and educational purposes provided the patient's identity is kept confidential. Nevertheless, it would be prudent to revise consent forms for surgery and autopsies to include the possibility that tissues removed can be stored or used for research and education. Good medical practice in pathology encourages a willingness to consult colleagues when in doubt, but advises that the treating clinician be informed if histopathological material is referred away for a second opinion. The Telemedicine Act of Malaysia (1997) requires practitioners outside Malaysia providing diagnosis through telepathology to hold a certificate to practice telemedicine issued by the Malaysian Medical Council. It is likely that the medico-legal scene in histopathology will change in the coming years with the advent of other new ancillary investigative techniques.
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Cheah PL, Looi LM. p53: an overview of over two decades of study. Malays J Pathol 2001; 23:9-16. [PMID: 16329542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
p53 is the most commonly mutated gene in human cancers. It encodes a 53 kilodalton protein with several evolutionarily conserved domains viz sequence-specific DNA binding, tetramerisation, SH3 molecule binding, C-terminal and N-terminal. Existing in the cell at a very low level and in a relatively inactive form, p53 protein is increased and activated during periods of cellular stress. Unlike other proteins, the increase in protein level and its activation result from modification of the protein rather than genetic transcriptional or translational upregulation. Normally, Mdm2 protein interacts with p53 protein and effectively targets it for ubiquitin proteolysis within an autoregulatory feedback loop. Phosphorylation at the N-terminus reduces p53 interaction with Mdm2 with a resultant increase in p53 protein level. Modification at the C and N termini via phosphorylation or acetylation upregulates binding to specific DNA targets increasing transcription of these downstream genes. The net effect of p53 protein increase and activation lies in arrest of the cell in cycle which allows time for repair of the incurred damage or apoptosis or death of the cell. Failure of these normal protective and adaptive mechanisms caused by mutation of the p53 gene with product of an abnormal protein, loss of p53 protein through interaction with and degradation by HPV E6 protein or overexpressed Mdm2 etc. permits DNA-damaged cells to continue replicating. Left unchecked, this frequently contributes to tumourigenesis. Various methods have been devised to screen for mutations of the p53 gene, still the most common source of failed p53 mechanism. These include immunohistochemical detection of mutated proteins or identification of altered electrophoretic mobility of mutated p53 sequences. Sequencing of the gene nonetheless remains the most accurate method for determination of mutation. Major advances have been made in p53 research but the most meaningful probably lies in the promising results achieved in tumour therapy where introduction of wild type p53 gene has resulted in regression of non-small-cell lung cancer (NSCLC). Many other notable developments in this field include description of p53 homologues, "gain of function" mutants, p53 polymorphisms, angiogenesis-inhibiting properties of wild type p53 protein etc.
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Affiliation(s)
- P L Cheah
- Department of Pathology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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Cheah PL, Kunaseegaran R, Looi LM. Expression of proliferating cell associated protein, Ki-67, supports cellular proliferation in WHO Class IV lupus nephritis. Malays J Pathol 2001; 23:27-30. [PMID: 16329544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Ki-67 expression in diffuse proliferative lupus nephritis, WHO Class IV, was compared against normal controls to establish that cellular proliferation is involved in the production of glomerular hypercellularity. Twenty-three histologically confirmed WHO Class IV lupus nephritis and 23 normal control renal tissue were immunohistochemically stained with a polyclonal antibody to Ki-67 (Dako) using the peroxidase labelled streptavidin bioitin kit (Dako). There were 20 females and 3 males, with 17 Chinese and 6 Malays in the WHO Class IV lupus nephritis group. Ages of patients ranged between 10-56 years with a mean of 31.9 years. The normal controls, 20 males and 3 females, and ethnically 9 Indians, 7 Malays, 2 Chinese, and 5 foreign nationals (4 Indonesians and 1 Bangladeshi), had an age range between 15-33 years (mean = 23.3 years). Sixteen (69.6%) WHO Class IV lupus nephritis and 8 (34.8%) normal controls demonstrated Ki-67 immunoreactivity in at least 1 glomerulus (p<0.05). Of the 256 WHO Class IV lupus nephritis non-sclerosed, glomeruli studied, 37 (14.5%) were Ki-67 immunopositive compared with normal controls where 16 (0.7%) of 2159 glomeruli demonstrated Ki-67 (p< 0.01). Cellular proliferative activity, as evidenced by Ki-67 expression, was significantly increased in WHO Class IV lupus nephritis confirming that cell proliferation contributes to glomerular hypercellularity.
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Affiliation(s)
- P L Cheah
- Department of Pathology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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Looi LM. Ethical issues in managed care. Med J Malaysia 2000; 55 Suppl B:9-13. [PMID: 11125526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Affiliation(s)
- L M Looi
- Department of Pathology, Faculty of Medcine, University of Malaya, 50603 Kuala Lumpur
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Abstract
OBJECTIVE To study the trend of different histological types of cervical carcinoma among the 3 major ethnic groups in Malaysia. METHODS All invasive cervical carcinoma histologically diagnosed for the first time in 1991-1992 and 1996-1997 at the University Hospital, Kuala Lumpur (UHKL) were reviewed for the following parameters; age, ethnic group, histological category. RESULTS One hundred and twenty-one and 145 cases were diagnosed in 1991-1992 and 1996-1997, respectively. During both periods, squamous was followed by adeno and adenosquamous carcinoma in frequency. Patients' mean ages ranged within the 4th decade for all 3 major histological types. Ethnically, an overall predilection for the Chinese was observed. While squamous carcinomas had declined among the Chinese and Malays, adenocarcinomas were noted to increase. The converse was observed among the Indians. CONCLUSIONS Ethnically, cervical carcinoma showed a predilection for Malaysians of Chinese descent. A decreasing incidence of squamous with a worrying increasing trend of adenocarcinoma was observed, like in other populations studied.
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Affiliation(s)
- P L Cheah
- Department of Pathology, University Hospital, University of Malaya, Kuala Lumpur, Malaysia
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Zheng WQ, Looi LM, Cheah PL. A comparison of the pattern of cathepsin-D expression in fibroadenoma, fibrocystic disease, preinvasive and invasive ductal breast carcinoma. Pathology 1999; 31:247-51. [PMID: 10503271 DOI: 10.1080/003130299105061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
In the metastatic process, proteolytic enzymes play an important role in mediating the passage of cancer cells through the basement membrane and extracellular matrix. We have compared cathepsin-D (CD) expression in a range of benign and malignant breast lesions so as to investigate its role in breast cancer progression. One hundred and sixty-two breast samples, comprising 18 fibroadenomas, 22 fibrocystic disease, 96 invasive ductal carcinoma and 26 lesions with intraductal carcinoma components, were evaluated for CD expression by the standard avidin-biotin-immunoperoxidase complex method on formalin-fixed, paraffin-embedded histological sections using a commercial antibody against human cathepsin-D. Of the invasive ductal carcinomas, 61.5% showed stromal cell CD positivity, whereas 48.9% expressed CD positivity in neoplastic cells. There was significant correlation between neoplastic cell and stromal CD positivity. The prevalences of CD positivity in both neoplastic and stromal cell components were significantly higher (P < 0.05 and P < 0.01, respectively) in histological grade III tumors compared to grades I and II carcinomas. CD expression by either neoplastic or stromal cells did not show significant correlation with patient age and tumor size. Only 15% of intraductal carcinomas were CD positive and expression was limited to neoplastic cells. Neither epithelial nor stromal cells in fibrocystic lesions and fibroadenomas were CD positive, but a weak to moderate positivity was observed within myoepithelial cells in mammary ducts. These findings provide insights into the mechanism whereby tumors with high histological grade mediate invasion into tissue. The role of stromal cells in tumor progression and the means of their recruitment deserve further study.
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Affiliation(s)
- W Q Zheng
- Department of Pathology, Faculty of Basic Medicine, Second Military Medical University, Shanghai, China.
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Cheah PL, Looi LM. Carcinoma of the uterine cervix: a review of its pathology and commentary on the problem in Malaysians. Malays J Pathol 1999; 21:1-15. [PMID: 10879274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Since its recognition about 150 years ago, there has been much progress in the understanding of the pathogenesis, prevention, early detection and management of carcinoma of the uterine cervix. Important historical landmarks include the (1) recognition of pre-invasive and pre-clinical lesions, and the devise of various systems for reporting these lesions, (2) improvements in diagnostic techniques particularly colposcopy, (3) advent of therapeutic procedures (electrocoagulation, cryotherapy, laser therapy and loop electrosurgical excision), and (4) recognition of the aetiological relationship between the human papillomavirus and cervical neoplasia. The susceptibility of the cervical transformation zone to malignant change is now well recognised. The WHO classification system remains the one most commonly utilised for histological reporting of cervical cancers. In the recent 1994 update, cervical carcinoma is divided into 3 main categories: squamous cell carcinoma, adenocarcinoma and other epithelial tumours. Squamous cell carcinoma (60-80%) predominates among invasive cervical carcinoma. Recognised variants include verrucous, warty (condylomatous), papillary squamous (transitional) and lymphoepithelioma-like carcinoma. Adenocarcinoma (5-15% of invasive carcinomas) shows an increasing trend in young females. Like its squamous counterpart, preinvasive and microinvasive versions are known. Variants such as mucinous, endometrioid, clear cell, mesonephric, serous, villoglandular and minimal deviation carcinoma are now defined. Adenosquamous carcinoma (5-25%), adenoid-cystic, adenoid-basal, neuroendocrine and undifferentiated carcinomas constitute other epithelial tumours of the cervix. The management of invasive cervical carcinoma remains heavily dependent on its stage. The FIGO staging system remains the most widely used. The 1995 update provides more definite criteria in subdividing stage IA tumours by delimiting stromal invasion of stage IA1 lesions to a maximum depth of 3 mm and a horizontal axis of 7 mm. In Malaysia, an appreciation of the cervical carcinoma problem has to take into consideration the population at risk, its multi-ethnicity, its socio-economic and geographical diversities and the constraints of the health care system. Females form 48.9% of the Malaysian population. 52.9% of them are in the sexually active age group of 15-50 years, indicating a significant population at risk for cervical carcinoma. Cervical carcinoma was the third most common cause of death due to solid tumours among Malaysian females in 1995 following carcinoma of the breast and respiratory tract. East Malaysia is predominantly rural with many communities having limited modern facilities. Such areas imply a lower educational and socio-economic status, raising the worry of a population at higher risk for developing cervical carcinoma. The population: doctor for Malaysia of 2153:1 compares poorly with nearby Singapore. Besides a shortage of doctors, there is also an uneven distribution of doctors, resulting in a ratio in East Malaysia of > 4000:1. Although Malaysia does not have a national cervical cancer-screening programme, many action plans and cancer awareness campaigns have been launched throughout the years, which appear to have made an impact as evidenced by the decreasing mortality rates from cervical carcinoma. Another interesting feature of cervical carcinoma in Malaysia relates to its multiethnic population. In Malaysian Chinese and Malay females, the prevalence of cervical carcinoma ranks second to breast cancer whereas the pattern is reversed in Malaysian Indian females. Studies into its aetiology and pathogenesis are being undertaken and may shed more light on this matter.
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Affiliation(s)
- P L Cheah
- Department of Pathology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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