EDXRF and the relative presence of K, Ca, Fe and as in amyloidogenic tissues

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.

Gastrointestinal stromal tumour in a jejunal diverticulum: The eighth reported case worldwide with a brief review of the literature

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.

Epithelial-mesenchymal transition profiles in triple negative breast carcinoma may explain its aggressive nature

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.

A review: Exploring the metabolic and structural characterisation of beta pleated amyloid fibril in human tissue using Raman spectrometry and SAXS

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.

Potential utility of telomere length assessment in breast cancer in a diagnostic histopathology setting

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.

Expanding the DARS phenotype: Late-adult onset myelopathy and leukoencephalopathy

A significant proportion of adult-onset neurological disorders remain diagnostic odysseys despite extensive evaluation. Hypomyelination with Brainstem and Spinal Cord Involvement and Leg Spasticity (HBSL) is an autosomal recessive disorder caused by mutations in the cytoplasmic aspartyl-tRNA synthetase (DARS) gene involved in mRNA translation. Clinical features of patients with DARS mutations include developmental delay, leg spasticity, cerebellar dysfunction, cognitive impairment and epilepsy. Most reported cases have been infantile-onset with severe neurological disability and neuroimaging abnormalities. To our knowledge, late- or adult-onset cases have never been reported in the literature. Here, we report for the first time, with video documentation and six-year clinical follow-up, an ethnic Malay patient with onset of spasticity and ataxia in late-adulthood, carrying a pathogenic DARS mutation discovered via whole-genome sequencing. His clinical and radiological findings were consistent with HBSL, but this diagnosis was not considered as, up until now, HBSL has only been reported with childhood/adolescent-onset. This case highlights that HBSL/DARS mutations should now be considered in the differential diagnosis of adult-onset spastic paraplegia and/or leukoencephalopathy.

Immunohistochemistry usage profile in a Malaysian tertiary hospital's histopathology laboratory

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.

FISHing for 1p19q codel in oligodendroglioma

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.

Screening for microsatellite instability in colorectal carcinoma: Practical utility of immunohistochemistry and PCR with fragment analysis in a diagnostic histopathology setting

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.

Cyclooxygenase-2 (COX2) expression in adenocarcinoma surpasses that of squamous cell carcinoma in the uterine cervix

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.

ERRATUM: Phyllodes tumours of the breast: retrospective analysis of a University Hospital's experience

No abstract available.

Phyllodes tumours of the breast: retrospective analysis of a University Hospital's experience

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.

Correlation of p16INK4a immunoexpression and human papillomavirus (HPV) detected by in-situ hybridization in cervical squamous neoplasia

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.

Research on cancer diagnosis in Malaysia: current status

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.

Actinomyces infection of the mastoid: a rare entity

A rare case of mastoid infection caused by actinomyces israelii is presented. This patient underwent exploratory mastoidectomy followed by long term oral pencillin. She responded well to the treatment and has been asymptomatic on follow up to date.

Histopathological landmarks of hepatocellular carcinoma in Malaysians

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.

Telomerase activation and human papillomavirus infection in invasive uterine cervical carcinoma in a set of Malaysian patients

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.

A comparison of the patterns of laminin expression in fibroadenoma, fibrocystic diseases, pre-invasive and invasive ductal breast carcinoma

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.

pS2 expression in infiltrating ductal carcinoma of the breast correlates with oestrogen receptor positivity but not with histological grade and lymph node status

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.

p53: an overview of over two decades of study

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.

Expression of proliferating cell associated protein, Ki-67, supports cellular proliferation in WHO Class IV lupus nephritis

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.

Malignant teratoma of the thyroid with predominantly neuroepithelial differentiation. Fine needle aspiration cytologic, histologic and immunocytochemical features of a case

BACKGROUND

Teratoma of the thyroid in adults is extremely rare, and most are malignant. Only nine cases have been adequately documented in the English-language literature, and there are no reports detailing the fine needle aspiration (FNA) cytologic characteristics.

CASE

A 32-year-old female presented with a left-sided nodular thyroid mass with left cervical lymphadenopathy. FNA cytology of the thyroid and lymph nodes was done. The cytologic and immunocytochemical features were that of a small round cell tumor with neuroepithelial (NE) differentiation, metastasizing to the cervical nodes. Microscopic study of the thyroidectomy specimen showed a tumor showing an NE pattern with occasional islands of squamous and cuboidal epithelium, leading to a diagnosis of malignant teratoma.

CONCLUSION

Knowledge of FNA cytologic features of rare but highly malignant lesions like thyroid teratomas allow early recognition so that suitable and possibly aggressive treatment protocols can be adopted in the hope of prolonging survival.

Recent trends in histological pattern of cervical carcinoma among three ethnic groups in Malaysia

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.

A comparison of the pattern of cathepsin-D expression in fibroadenoma, fibrocystic disease, preinvasive and invasive ductal breast carcinoma

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.

Carcinoma of the uterine cervix: a review of its pathology and commentary on the problem in Malaysians

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.

Immunotactoid glomerulopathy--an unusual deposition disease: report of the first Malaysian case

A 31-year-old Malay female presented with nephrotic syndrome without renal impairment. Renal biopsy features were in keeping with immunotactoid glomerulopathy (ITG). Non-Congophilic deposits were seen causing thickening of the glomerular capillary basement membrane with segmental accentuation, and widening of the mesangium. Immunofluorescence examination showed moderate amounts of IgG and C3 in the glomerular capillary walls with some in the mesangium. Ultrastructurally, 20-nm thick fibrils with microtubular organisation were present predominantly in the subendothelial region with similar fibrils in the mesangium. Although immunotactoid glomerulopathy and fibrillary glomerulonephritis (FG) have been recognised as entities with extracellular fibrillary material in the kidney, to date much remains to be clarified regarding these 2 conditions. While the renal biopsy findings in this patient are consistent with ITG, her clinical presentation is unlike that of usual ITG in that she is of a much younger age and has no associated haemopoietic disorder. Response to initial treatment of 8 weeks of prednisolone therapy was poor.

Biology and pathological associations of the human papillomaviruses: a review

Historical cottontail rabbit papillomavirus studies raised early indications of a mammalian DNA oncogenic virus. Today, molecular cloning recognises numerous animal and human papillomaviruses (HPVs) and the development of in vitro transformation assays has escalated oncological research in HPVs. Currently, their detection and typing in tissues is usually by Southern blotting, in-situ hybridization and polymerase chain reaction methods. The complete papillomavirus virion constitutes a protein coat (capsid) surrounding a circular, double-stranded DNA organised into coding and non-coding regions. 8 early (E1-E8) open reading frames (ORFs) and 2 late (L1, L2) ORFs have been identified in the coding region of all papillomaviruses. The early ORFs encode proteins which interact with the host genome to produce new viral DNA while late ORFs are activated only after viral DNA replication and encode for viral capsid proteins. All papillomaviruses are obligatory intranuclear organisms with specific tropism for keratinocytes. Three possible courses of events can follow papillomaviruses entry into cells: (1) viral DNA are maintained as intranuclear, extrachromosomal, circular DNA episomes, which replicates synchronously with the host cell, establishing a latent infection; (2) conversion from latent into productive infection with assembly of complete infective virions; (3) integration of viral DNA into host cellular genome, a phenomenon seen in HPV infections associated with malignant transformation. Human papillomaviruses (HPVs) essentially induce skin and mucosal epithelial lesions. Various skin warts are well known to be HPV-associated (HPVs 1, 2, 3, 7 and 10). Besides HPVs 3 and 10, HPVs 5, 8, 17 and 20 have been recovered from Epidermodysplasia verruciformis lesions. Anogenital condyloma acuminatum, strongly linked with HPVs 6 and 11 are probably sexually transmitted. The same HPVs, demonstrable in recurrent juvenile laryngeal papillomas, are probably transmitted by passage through an infected birth canal. HPVs described in uterine cervical lesions are generally categorized into those associated with high (16, 18), intermediate (31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68) and low (6, 11, 26, 40, 42, 43, 44, 53, 54, 55, 62, 66) risk of cervical squamous carcinoma. Cervical adenocarcinoma, clear cell carcinoma and small cell neuroendocrine carcinoma have also been linked to HPVs, especially HPV18. Other lesions reported to be HPV-associated are: papillomas, dysplasia and carcinomas in the nasal cavity (HPV 6, 11, 57); squamous papilloma, condyloma acuminatum, and verruca vulgaris of the oral cavity (HPV 6, 11), oral focal epithelial hyperplasia (HPV 13, 32); warty lip lesions (HPV 2): and conjunctival papillomas (HPV 6, 11).

C-erbB-2 oncoprotein amplification in infiltrating ductal carcinoma of breast relates to high histological grade and loss of oestrogen receptor protein

Eighty-six infiltrating ductal carcinoma of breast were studied by the standard avidin-biotin complex immunoperoxidase method on formalin-fixed, paraffin-embedded tissue sections, for oestrogen receptor (ER) protein and c-erbB-2 oncoprotein expression. They were categorized according to the modified Bloom and Richardson criteria into three histological grades. 21% tumours were ER positive while 44% were c-erbB-2 positive. Of ER positive tumours, 33.3% were c-erbB-2 positive whereas the c-erbB-2 positivity rate was much higher (47.1%) in ER negative tumours. Only 16% of c-erbB-2 positive tumours were ER positive while 25% of c-erbB-2 negative tumours were ER positive. This negative relationship between ER and c-erbB-2 expression was statistically significant (Mc Nemar's test, p < 0.005). The ER positivity rate did not vary significantly with histological grade. However, c-erbB-2 overexpression was significantly more prevalent in grade III tumours compared with grade I and II tumours (Chi-square test, p < 0.005). Since the c-erbB-2 oncogene has extensive structural homology to the epidermal growth factor receptor (EGFR) gene, we expect that c-erbB-2 oncoprotein would share functional similarities with EGFR leading to both loss of oestrogen receptor and poor prognosis in breast cancer. Its overexpression can be expected to relate to more aggressive tumour proliferation and may explain its correlation with high histological grade, a known indicator of aggressive cancer behaviour. As there is no indication that ER protein activity contributes to advancement in histological grade, it would appear that cellular dedifferentiation precedes ER loss during malignant transformation. It has been mooted that ER positive breast cancers which also show c-erbB-2 oncoprotein overexpression have a poorer response to hormonal therapy. The use of this parameter in the routine assessment of breast cancer patients may identify subsets of patients for more aggressive therapy.

Enhanced major histocompatibility complex (MHC) class II antigen expression in lupus nephritis

Thirty-eight cases of lupus nephritis, all satisfying the American Rheumatism Association criteria for diagnosis of systemic lupus erythematosus (SLE), with renal involvement and biopsy were immunohistochemically studied for the expression of HLA-DR (DAKO: HLA-DR/alpha, TAL.1B5), one of the three known families belonging to the class II major histocompatibility complex (MHC), using a standard streptavidin-biotin-peroxidase method. 20 nephrectomies performed for renal trauma and tumours constituted the normal controls. Of the lupus nephritis cases, 34 were females and 4 males. Ethnically, 20 were Chinese, 13 Malay, 4 Indian and 1 of indigenous origin. Their ages ranged from 16 to 59 years (mean of 31 years). Histologically, 23 expressed World Health Organisation (WHO) class IV (diffuse proliferative), 10 WHO class V (diffuse membranous), 4 WHO class II (pure mesangiopathy) and 1 WHO class III (segmental and focal proliferative) nephritis. Activity scores ranged between 5 to 19 (mean = 8.6) and chronicity scored between 2 to 7 (mean = 3.2) on a standard scoring system. Similar to other studies, HLA-DR was expressed in the glomerular capillaries and peritubular capillaries of all and mesangium, tubules (proximal, distal and collecting), veins and arterioles of some normal controls. Interestingly, HLA-DR expression was noted in the arteries of 25% of the normal controls, a finding hitherto not reported. The frequency of lupus nephritis cases expressing HLA-DR in the various anatomical components did not differ significantly from the normal controls except that HLA-DR expression in arteries and arterioles was seen at a significantly increased frequency (p < 0.01) in lupus nephritis. This increased expression did not correlate with the WHO class, activity or chronicity scores. It therefore appears that MHC class II shows increased expression in the arterial system of lupus nephritis kidneys. The significance of this is unclear but could be related to heightened (gamma-interferon activation which may be a de novo phenomenon or result of T cell proliferation and activation in SLE.

Comparison of two 1-week low-dose omeprazole triple therapies--optimal treatment for Helicobacter pylori infection?

OBJECTIVES

To determine and compare the efficacy and tolerability of two 1-week regimen comprising omeprazole, clarithromycin and amoxycillin or metronidazole in the eradication of Helicobacter pylori, and to determine the influence of bacterial resistance to metronidazole and clarithromycin on the outcome of treatment.

PATIENTS AND METHODS

Patients with unequivocal evidence of H. pylori infection based on culture, histology and rapid urease test of both antrum and corpus biopsies were recruited for the study. The study was a randomized, investigator-blind, comparative study. Patients received either omeprazole 20 mg o.m., clarithromycin 250 mg b.d. and amoxycillin 500 mg b.d. (OAC) or omeprazole 20 mg o.m., metronidazole 400 mg b.d. and clarithromycin 250 mg b.d. (OMC) for 1 week. Patients were assessed for successful eradication, which was defined as absence of bacteria in all tests (culture, histology and urease test on both antral and corpus biopsies), at least 4 weeks after completion of therapy.

RESULTS

Eighty-two patients were recruited for the study. Eradication rates on intention-to-treat analysis were--OAC: 36/41 (87.8%, 95% CI: 73.8, 95.9); OMC: 33/41 (80.5%, 95% CI: 65.1, 91.2). On per protocol analysis were--OAC: 36/40 (90%, 95% CI: 76.3, 97.2); OMC: 32/38 (84.2%, 95% CI: 68.7, 94.0). All side-effects encountered were mild and no patient discontinued treatment because of intolerance to medications. The most common side-effects were altered taste (OAC 31.7%, OMC 53.7%) and lethargy (OAC 14.6%, OMC 19.5%). Pre-treatment metronidazole resistance was encountered in 34/63 (54.0%) patients. No bacterial strains were found with primary resistance to clarithromycin. Metronidazole resistance did not significantly affect eradication rates. Emergence of resistance to clarithromycin was not seen post-therapy.

CONCLUSIONS

Both the OAC and the OMC regimens were convenient and well-tolerated treatments for H. pylori. However, eradication rates were lower than anticipated.

Correlation between oestrogen receptor protein expression in infiltrating ductal carcinoma of the breast by immunohistochemistry and cytosol measurements

Fresh frozen neoplastic tissues from 70 infiltrating ductal breast carcinomas were analysed for cytosolic oestrogen receptor (ER) protein content using a solid phase enzyme immunoassay (EIA) method based on a "sandwich" principle (Abbott ER-EIA monoclonal). Formalin-fixed, paraffin-embedded sections from the same carcinomas were examined for nuclear immunoreactivity against a monoclonal antibody for ER protein (Dako) using the standard avidin-biotin complex immunoperoxidase (IP) method after microwave antigen retrieval. The degree of ER positivity by IP was also scored according to a visual estimation of the percentage of cells expressing immunopositivity and the intensity of staining. Twenty-eight (40%) of the carcinomas were ER-positive by EIA and 34 (48.6%) were positive by IP. Twenty-five (35.7%) were ER-positive and 33 (47.1%) were ER-negative by both methods. Nine (12.9%) were ER-negative by EIA but were positive by IP, this discrepancy being ascribed to sampling inadequacy for EIA. However, 3 (4.3%) tumours were ER-positive by EIA and negative by IP. This discrepancy may be variously due to inadequate antigen retrieval, faulty technique and the possibility that the two methods do not measure identical ER proteins. IP appears to have an advantage over EIA in that it has a higher pick-up rate, does not require fresh tissue and can be applied to archival material. However, to reduce false negative estimations, it may be necessary to run IP staining using more than one ER antibody. Standardisation of the IP method for ER is desirable before this method is to be widely adopted in Malaysian laboratories. Quantitation of ER positivity by IP scoring correlated poorly with actual cytosolic levels. Caution should be exercised in attaching patient management value to visual IP scoring.

Histomorphological patterns of renal amyloidosis: a correlation between histology and chemical type of amyloidosis

A retrospective study was conducted to investigate whether there was a correlation between the histological pattern of renal amyloidosis, the chemical type of amyloid protein involved and the clinical presentation. Eighteen consecutive cases of systemic amyloidosis that had renal biopsies processed and examined histopathologically at the Department of Pathology, Faculty of Medicine, University of Malaya, Kuala Lumpur were reviewed. The age range of patients was 25 to 64 yrs (mean, 46 yrs). The male:female ratio was 2.6:1. Three patients were Malay, 9 Chinese, 3 Indian, 1 Indonesian, 1 Iban, and 1 Bisaya. According to the predominant site of amyloid deposition, 14 cases showed a glomerular pattern and 4 a vascular pattern. 8 cases were designated as 2 anti-human amyloid-A (AA) amyloidosis on the basis of permanganate-sensitivity and immunoreactivity of deposits with anti-human AA protein antibody. Ten cases contained deposits that were permanganate-resistant and nonimmunoreactive for AA protein and were designated as AL in type. The histomorphologic pattern of renal amyloidosis did not provide a reliable means of differentiating AA from AL amyloidosis. The glomerular pattern tended to present with renal manifestations such as nephrotic syndrome and chronic renal failure, whereas the vascular pattern tended to present with nonrenal manifestations such as diarrhoea. These findings may have a bearing on the pathophysiology of amyloidosis and provide clues to appropriate management.

Correlation between histological grade and c-erbB2 oncoprotein overexpression in infiltrating ductal carcinoma of breast

One hundred and twelve infiltrating ductal carcinoma of breast were studied by the standard avidinbiotin complex immunoperoxidase method on formalin-fixed, paraffin-embedded tissue sections, using a monoclonal antibody to c-erbB-2 oncoprotein. The same tumours were assessed and scored according to the Bloom and Richardson criteria into three histological grades. The distribution of tumours according to grade were: 8 Grade I, 34 Grade II and 70 Grade III. Forty-three (38.4%) tumours showed positive membrane staining for c-erbB-2 oncoprotein. These comprised 7 Grade II and 36 Grade III tumours with c-erbB-2 immunopositivity rates of 20.6% and 51.4% respectively. The oncoprotein was not expressed by Grade I tumours. This study shows a good correlation between c-erbB-2 expression and histological grade, a known prognostic indicator of invasive breast carcinoma. Because the c-erbB-2 oncogene has extensive structural homology to the epidermal growth factor receptor gene, its overexpression can be expected to result in more aggressive tumour behaviour. While it may be regarded as another indicator of poor prognosis breast cancers, its value in the selection of carcinomas less responsive to hormonal therapy and those more suitable for immunotherapy than chemotherapy has been mooted but remains to be clarified.

Problems in the histological assessment of hydatidiform moles: a study on consensus diagnosis and ploidy status by fluorescent in situ hybridisation

Hydropic villi in products of conception continue to pose a diagnostic problem for the anatomical pathologist. It is important to distinguish between complete hydatidiform mole (CM), partial hydatidiform mole (PM) and hydropic degeneration (HD), as hydatidiform moles (especially CM) have a tendency to develop persistent trophoblastic disease. Several studies have demonstrated interobserver variability in the diagnosis of the three conditions, but there have been no studies testing the accuracy of the consensus diagnosis of pathologists experienced in the field. In this study four anatomical pathologists with experience in diagnosing hydatidiform moles selected five cases of HD, seven cases of PM and ten cases of CM on the basis of consensus diagnosis using established criteria. Ploidy studies were done on these 22 cases using fluorescent in situ hybridisation. The 15 cases of HD and CM were diploid, confirming the histological diagnosis. However only five of the seven cases of PM were triploid, the other two being diploid. Review of these two diploid cases showed a mixture of small and large villi with moderate to marked trophoblastic proliferation. On the basis of the significant trophoblastic proliferation and the DNA information, the two cases were reclassified as early complete moles. This study demonstrates that even pathologists experienced in the field have difficulty separating PM from CM. The findings suggest that, in the absence of DNA information, a lesion with hydropic villi showing moderate to marked trophoblastic proliferation should be classified as a complete mole, even if there is a mixture of small and large villi. Ploidy studies are an important adjunct to histological diagnosis, especially when there is an overlap of features.

Implications of p53 protein expression in clear cell sarcoma of the kidney

Eight histologically-confirmed cases of clear cell sarcoma of the kidney (CCSK) were studied for possible mutations in the p53 tumor suppressor gene by the immunohistochemical demonstration of mutant p53 proteins using a monoclonal (DO7: Dako) and a polyclonal (AB565: Chemicon) antibody to p53 protein. All cases exhibited p53 protein nuclear immunopositivity, although in varying numbers of tumor cells and with different staining intensities. p53 protein (DO7 or AB565) was expressed in < 25% of the tumor cells in four (50%) of the cases, including the one case with a known long term survival of 13 years from the time of diagnosis. The other tumors showed p53 protein immunopositivity in > 25% of the tumor cells when stained with either DO7 or AB565 or both. The intensity of staining, graded on visual impression into weak, moderate or strong, did not correlate well with the ratio of positive staining tumor cells. While this study is unable to clarify the relative prevalence and importance of p53 mutational events in the pathogenesis of this aggressive renal tumor of childhood, it is reasonably suggestive that alterations in the p53 tumor suppressor gene do occur in CCSK.

Immunohistochemical expression of p53 proteins in Wilms' tumour: a possible association with the histological prognostic parameter of anaplasia

Wilms' tumour (nephroblastoma) has been associated with chromosomal abnormalities at the 11p13, 11p15 and 16q regions. A study into the possibility of mutations occurring within p53, the ubiquitous adult tumour suppressor gene, in Wilms' tumour was carried out. Thirty-eight cases were studied. Of these 36 were categorised into the favourable histology group and two into the unfavourable histology group based on the National Wilms' Tumour Study criteria. Archival formalin-fixed, paraffin-embedded tissue sections from each case were stained with a polyclonal (AB565:Chemicon) and a monoclonal (DO7:Dako) antibody raised against p53 protein using a peroxidase-labelled streptavidin biotin kit (Dako). 'Cure' (disease-free survival of 60 months or longer) was documented in 39% of cases with favourable histology tumours. Eleven percent in this group succumbed to the disease. Both cases with unfavourable histology died. Four out of 36 (11%) tumours with favourable histology demonstrated weak to moderate staining with both AB565 and DO7 in more than 75% of tumour cells. In contrast, p53 protein expression in unfavourable histology tumours was significantly increased compared with the favourable histology group (P = 0.021) with both cases demonstrating immunopositivity in > 75% of tumour cells when stained with AB565 and DO7. The intensity of staining ranged from moderate to strong in both cases. It appears from this preliminary study that the immunohistochemical expression of p53 protein in Wilms' tumour, presumably a result of mutation in the p53 tumour suppressor gene, correlates with histological classification, histological categorisation being one of the useful features in the prognostic assessment of Wilms' tumours.

Squamous cell carcinoma antigen as an adjunct tumour marker in primary carcinoma of the lung

AIMS

To determine (1) the detection rate of primary carcinoma of the lung by serological assay of CEA (carcinoembryonic antigen); and (2) whether addition of seroassay of squamous cell carcinoma related antigen before treatment improves detection sensitivity.

METHODS

A prospective study spanning 27 months was conducted at the University Hospital, Kuala Lumpur. Serum CEA (Abbott IMx) and serum squamous cell carcinoma antigen (Abbott IMx) from patients clinically suspected of having primary carcinoma of the lung, were assayed using the microparticle enzyme immunoassay method.

RESULTS

Thirty seven cases of histologically confirmed primary lung carcinoma were studied. Of these, 17 were squamous cell carcinomas, 10 adenocarcinomas, nine small cell carcinomas, and one large cell carcinoma. The patients' ages ranged from 34-82 years. The male:female ratio was 3.6:1. Squamous cell carcinoma antigen was raised above the cutoff value of 1.5 ng/ml in 94.1% of squamous cell carcinomas, 20.0% of adenocarcinomas, and 11.1% of small cell carcinomas. By comparison, CEA was raised above the cutoff value of 3.0 ng/ml in 70.6% of squamous cell carcinomas, 77.8% of small cell carcinomas, and 100% of adenocarcinomas. CEA and squamous cell carcinoma antigen were not raised in the patient with large cell carcinoma and in 14 healthy volunteers. None of 15 patients with a variety of benign lung diseases showed a rise of CEA, while two patients--a 25 year old Indian woman with pneumonia and a 64 year old Malay man with bronchial asthma--had raised squamous cell carcinoma antigen values above the cutoff. Serum CEA and squamous cell carcinoma antigen values did not seem to correlate with stage or degree of differentiation of the tumours.

CONCLUSIONS

The findings suggest that CEA is a good general marker for carcinoma, particularly adenocarcinoma. In contrast, squamous cell carcinoma antigen is more specific for squamous carcinoma.

Human papillomavirus related diseases in Malaysians

The surge of information on the aetiological association of the human papillomavirus (HPV) with some epithelial tumours emanating from various centres has prompted the initiation of a large-scale retrospective study at the Department of Pathology, University Hospital Kuala Lumpur to determine the prevalence and importance of this virus in some epithelial tumours of Malaysian patients. A retrospective analysis of 100 cases of large cell non-keratinising carcinoma of the uterine cervix by in-situ hybridisation on archival formalin-fixed, paraffin-embedded tissue has revealed the presence of HPV type 16 in 47% and type 18 in 41% of cases. This gives an overall detection rate of 88% of the two HPV types most commonly encountered in cervical carcinomas. Except for the unusually high frequency of HPV 18 detected in the cases, the overall prevalence is comparable to that reported in studies from most other centres. Although this higher frequency of HPV 18 may be due to geographical variation, the selection of the large cell non-keratinising type of squamous cell cervical carcinoma for study remains a possible reason for this phenomenon. In comparison to cervical carcinomas, HPV appears to be uncommon in penile carcinomas and HPV 6 was detected in only 1 of 23 cases studied.

Alterations in mucin type: an indicator for suspicion of malignant gastric transformation

Mucins are produced by both benign and malignant gastric epithelium. In general, mucins can be classified into neutral and acidic mucins. The latter are of 2 major types, sulphated (sulphomucins) and carboxylated (sialomucins). A retrospective study was initiated at the Department of Pathology, University Hospital, Kuala Lumpur to histochemically study the mucin profiles of cases of intestinal (IGC) and diffuse (DGC) types of gastric carcinoma in Malaysian patients to determine whether a significant change of mucin type occurs in the event of malignant transformation. 42 IGC and 37 DGC were subjected to alcian blue-periodic acid Schiff and high iron diamine-alcian blue histochemical staining. In addition, 18 cases of gastrectomies performed for benign lesions in the stomach served as normal controls. The number of cases of IGC and DGC which exhibited sulphomucin production was significantly increased (p < 0.001) compared to normal controls. Also, the number of cases of DGC which produced neutral mucin were significantly less (p < 0.05) than the control group. However, there was no significant difference between the number of IGC and DGC cases which demonstrated sialomucin production and normal controls. It appears that while not pathognomonic, a lack of neutral mucin production should alert the pathologist to the possibility of a gastric malignancy, in particular DGC. The likelihood of a malignant lesion would be further supported if there is an increased sulphomucin production.

Expression of placental proteins in complete and partial hydatidiform moles

Examination of routinely stained haematoxylin and eosin sections may sometimes prove inadequate in differentiating partial hydatidiform moles (PHM) from complete hydatidiform moles (CHM). While cytogenetic analysis can aid in the distinction, such facilities are not always available. The possibility of using immunohistochemistry to aid in the differentiation was studied. Twenty-five histologically proven CHM and 11 PHM were studied for their patterns of expression of human chorionic gonadotrophin (hCG), human placental lactogen (hPL) and placental alkaline phosphatase (PIAP). All CHM stained diffusely with hCG and focally with both hPL and PIAP irrespective of gestational age. Of PHM, 63.6% were diffusely positive for hCG, 27.3% for hPL and 54.5% for PIAP; the rest were focally positive. The hCG pattern changed from diffuse to focal with increasing gestational age of PHM, while those of hPL and PIAP became increasingly diffuse with gestational age. While these protein expressions may be applied in differentiating late PHM from CHM, it is not useful in first trimester cases. The most helpful application is that focal expression of hCG and diffuse expressions of hPL and PIAP is not seen in CHM, thereby excluding such a diagnosis. PHM, in contrast, can show either diffuse or focal expression of all 3 antigens.

Aggressive angiomyxoma of the vulva with an unusual vascular finding

We report the first documented Malaysian case of aggressive angiomyxoma (AAM) of the vulva. A 56-yr-old woman of Indian ethnic origin presented with a vulval lesion which was clinically mistaken for a Bartholin's cyst. The lesion was surgically excised and a diagnosis of AAM was made histologically. Of particular interest was the finding of foamy and mononuclear inflammatory cells and fibrin in the walls of most of the lesional blood vessels. The patient recovered uneventfully and remains without tumor recurrence at the time of writing 37 mths after initial presentation.

Hydatidiform molar pregnancy in Malaysian women: a histopathological study from the University Hospital, Kuala Lumpur

A review of gestational trophoblastic disease diagnosed at the Department of Pathology, University Hospital, Kuala Lumpur from January 1989 to December 1990 using established histological criteria showed 25 complete hydatidiform moles (CHM), 11 partial hydatidiform moles (PHM), 1 invasive mole and 2 choriocarcinoma. The ages of the patients with CHM ranged from 21 to 43 years (mean = 28.5 years) and PHM 20 to 33 years (mean = 27.5 years). The invasive mole occurred in a 42-year-old Malay woman. The two patients with choriocarcinoma were both Chinese and 41 and 46-years old respectively. During the same period, 1,062 non-molar abortions and 13,115 births, inclusive of livebirths and stillbirths were recorded at the University Hospital. The incidence rate of hydatidiform moles was thus estimated to be 1:384 pregnancies. PHM constituted 30% of all molar pregnancies. Hydatidiform moles occurred among the Malays, Chinese and Indians at the rate of 2.43, 2.66 and 3.29 per 1,000 pregnancies respectively. It appears that hydatidiform molar pregnancy has the highest prevalence among the Indians, a finding similar to an earlier Singapore study.

An immunohistochemical study comparing clear cell sarcoma of the kidney and Wilms' tumor

This study explores immunohistochemical characteristics that may be of diagnostic value in differentiating clear cell sarcoma of the kidney (CCSK) from Wilms' tumor (WT) and may provide some insight into the histogenesis of CCSK. Formalin-fixed, paraffin-embedded sections of 8 CCSK and 9 WT were stained, using the standard avidin-biotin peroxidase complex method, for vimentin (VIM), Factor-8 related antigen (F8A), epithelial membrane antigen (EMA), desmin (DES), S-100 protein and Mac 387. CCSK cells consistently exhibited moderate to strong diffuse cytoplasmic positivity for VIM and were negative for F8A, EMA, DES, S-100 and Mac 387. In contrast, only patchy groups of stromal cells and primitive glomeruloid structures in WT exhibited VIM-positivity. Blastemal cells were VIM-negative. Stromal cells with rhabdomyomatous differentiation exhibited cytoplasmic positivity for DES. Epithelial cells of maturing tubular structures showed EMA-positivity whereas immature tubular structures were EMA-negative. Neither blastemal, stromal nor epithelial elements in WT were positive for F8A, S-100 or Mac 387. Podocytes and mesangial cells of glomeruli in 3 mid-trimester human abortuses (controls) exhibited moderate to strong VIM-positivity. The importance of differentiating CCSK from WT has been repeatedly emphasized because of its poorer prognosis and the necessity of adding Adriamycin to the chemotherapeutic regime. The consistent VIM-positivity of CCSK cells can be a useful feature in differentiating it from "blastemal-predominant" WT, with which it is often confused. Although vimentin expression by CCSK cells is consistent with a mesenchymal character, the possibility of a histogenetic link with glomerular podocytes or mesangial cells should also be considered.

Rare case of huge retroperitoneal liposarcoma presenting as a gynaecological problem

A large retroperitoneal liposarcoma presented clinically as an ovarian tumour in an infertile woman. The importance of computed tomography in the differential diagnosis and the appropriate management of retroperitoneal liposarcoma is presented with a review of the relevant literature.

In situ hybridisation: principles and applications

In situ hybridisation (ISH) is based on the complementary pairing of labelled DNA or RNA probes with normal or abnormal nucleic acid sequences in intact chromosomes, cells or tissue sections. Compared with other molecular biology techniques applicable to anatomical pathology, ISH enjoys better rapport with histopathologists because of its similarity to immunohistochemistry. It has the unique advantage over other molecular biology techniques--largely based on probe hybridisation with nucleic acid extracted from homogenised tissue samples--of allowing localisation and visualisation of target nucleic acid sequences within morphologically identifiable cells or cellular structures. Probes for ISH may bear radioactive or non-radioactive labels. Isotopic probes (3H, 32P, 35S, 125I) are generally more sensitive than non-isotopic ones but are less stable, require longer processing times and stringent disposal methods. Numerous non-isotopic labels have been used; of these biotin and digoxigenin are the reporters of choice. Optimised non-isotopic systems of equivalent sensitivity to those which use radioactive-labelled probes have been described. In ISH, finding the optimal balance between good morphological preservation of cells and strong hybridisation signals is crucial. Tissue fixation and retention of cytoskeletal structures, unfortunately, impede diffusion of probes into tissues. ISH sensitivity is also influenced by inherent properties of the probe and hybridisation conditions. Although ISH is largely a research tool, it is already making strong inroads into diagnostic histopathology. It has been applied for the detection of various infective agents particularly CMV, HPV, HIV, JC virus, B19 parvovirus, HSV-1, EBV, HBV, hepatitis delta virus, Chlamydia trachomatis, salmonella and mycoplasma in tissue sections.(ABSTRACT TRUNCATED AT 250 WORDS)