Association between autophagy and KRAS mutation with clinicopathological variables in colorectal cancer patients

Autophagy is a host defensive mechanism responsible for eliminating harmful cellular components through lysosomal degradation. Autophagy has been known to either promote or suppress various cancers including colorectal cancer (CRC). KRAS mutation serves as an important predictive marker for epidermal growth factor receptor (EGFR)-targeted therapies in CRC. However, the relationship between autophagy and KRAS mutation in CRC is not well-studied. In this single-centre study, 92 formalin-fixed paraffin-embedded (FFPE) tissues of CRC patients (42 Malaysian Chinese and 50 Indonesian) were collected and KRAS mutational status was determined by quantitative PCR (qPCR) (n=92) while the expression of autophagy effector (p62, LC3A and LC3B) was examined by immunohistochemistry (IHC) (n=48). The outcomes of each were then associated with the clinicopathological variables (n=48). Our findings demonstrated that the female CRC patients have a higher tendency in developing KRAS mutation in the Malaysian Chinese population (p<0.05). Expression of autophagy effector LC3A was highly associated with the tumour grade in CRC (p<0.001) but not with other clinicopathological parameters. Lastly, the survival analysis did not yield a statistically significant outcome. Overall, this small cohort study concluded that KRAS mutation and autophagy effectors are not good prognostic markers for CRC patients.

High expression of LC3A, LC3B, and p62/SQSTM1 autophagic proteins in human colonic ganglion cells

INTRODUCTION

Autophagy is a mechanism that degrades large damaged organelles and misfolded proteins to maintain the homeostasis in all cells. It plays double-faceted roles in tumourigenesis and prevention of various cancers. In our side observation of investigating the prognostic value of autophagy in colorectal cancer (CRC), we found high expression of autophagy proteins (LC3A, LC3B, and p62/SQSTM1) in the colonic ganglion cells. To our best understanding, this is the first paper reporting such finding.

MATERIALS AND METHODS

Formalin-fixed paraffin-embedded (FFPE) CRC tissues blocks were retrieved and confirmed by haematoxylin & eosin (H&E) staining. Immunohistochemistry (IHC) targeting autophagy proteins (LC3A, LC3B, and p62/SQSTM1) was then performed followed by pathological examination.

RESULTS

All three autophagy proteins were present in both normal and tumour tissues of CRC patients. Interestingly, high expression of autophagy proteins in colonic ganglion cells was consistently seen regardless of tissue type (normal or cancer) or tumour site (caecum, ascending, transverse, descending, sigmoid colon and rectum).

CONCLUSIONS

This work highlights the high autophagic activities in human colonic ganglion cells.

pSTAT3 and MYC in Epstein-Barr virus-positive diffuse large B-cell lymphoma

INTRODUCTION

Epstein-Barr Virus (EBV) is associated with several B-cell non-Hodgkin's lymphoma (NHL), but the role of EBV in diffuse large B-cell lymphoma (DLBCL) is poorly defined. Several studies indicated the expression of phosphorylated STAT3 (pSTAT3) is predominant in EBV(+)- DLBCL, of which its activated form can promote the downstream oncogenes expression such as c-MYC. c-MYC gene rearrangements are frequently found in aggressive lymphoma with inferior prognosis. Furthermore, EBV is a co-factor of MYC dysregulation. JAK1/STAT3 could be the downstream pathway of EBV and deregulates MYC. To confirm the involvement of EBV in JAK1/ STAT3 activation and MYC deregulation, association of EBV, pSTAT3 and MYC in EBV(+)- DLBCL cases were studied. The presence of pSTAT3 and its upstream proteins: pJAK1 is identify to delineate the role of EBV in JAK1/STAT3 pathway.

MATERIALS AND METHODS

51 cases of DLBCL paraffin-embedded tissue samples were retrieved from a single private hospital in Kuala Lumpur, Malaysia. EBER-ISH was performed to identify the EBV expression; ten EBV(+)-DLBCL cases subjected to immunohistochemistry for LMP1, pJAK1, pSTAT3 and MYC; FISH assay for c-MYC gene rearrangement.

RESULTS

Among 10 cases of EBV(+)-DLBCL, 90% were non-GCB subtype (p=0.011), 88.9% expressed LMP1. 40% EBV(+)-DLBCL had pJAK1 expression.

CONCLUSION

66.7% EBV(+)-DLBCL showed the positivity of pSTAT3, which implies the involvement of EBV in constitutive JAK/STAT pathway. 44.5% EBV(+)-DLBCL have co-expression of pSTAT3 and MYC, but all EBV(+)-DLBCL was absence with c-MYC gene rearrangement. The finding of clinical samples might shed lights to the lymphomagenesis of EBV associated with non-GCB subtypes, and the potential therapy for pSTAT3-mediated pathway.

Epstein-Barr virus infection in B-cell Non-Hodgkin's Lymphomas of the oral and maxillofacial region: Is there any evidence?

INTRODUCTION

Epstein-Barr virus (EBV) might be an aetiological agent involved in the pathogenesis of certain Non-Hodgkin's Lymphomas (NHLs). EBV infection has been diagnosed by serologic testing within the tumour biopsies of patients with NHL. However, the association between EBV and NHL is inconsistent with a preference for certain anatomic sites, histologic subtypes and immunosuppressed patients. The objective of this study was to characterise the B-cell NHLs of the oral cavity and maxillofacial region using histological and immunophenotypical techniques and to determine its association with EBV infection.

MATERIALS AND METHODS

This was a descriptive cross-sectional study that included 14 cases of B-cell NHLs of the oral cavity and maxillofacial region. The haematopoietic and lymphoid tissue tumours classification of WHO was used to categorize the cases. In-situ hybridisation for EBV-encoded RNA was performed to confirm the EBV infection.

RESULTS

The average age of the patients included in the study was found to be 48.8 ± 23 years with a higher female to male ratio (1.3:1). Our study suggested that diffuse large B-cell lymphomas (DLBCLs) and Burkitt's lymphomas (BLs) constitute the predominant subtypes of lymphomas affecting the oral cavity and maxillofacial regions.

CONCLUSION

The findings from our study support the view that at least a relatively smaller proportion of B-cell NHLs that occur in the oral cavity and maxillofacial region do not have a pathogenic association with EBV.

Pattern of hMLH1, hMSH2 and hMSH6 expression and clinical characteristics in a sample of Malaysian colorectal carcinoma cases

Malignant transformation from normal colonic mucosa to carcinomas may be accelerated by genetic loss or inactivation of genes of the DNA mismatch repair system. The aim of the study was to determine the local incidence and pattern of immunohistochemical expression of mismatch repair proteins namely: hMLH1, hMSH2 and hMSH6 in a series of colorectal carcinomas (CRCs) and correlate this to their clinical and pathological features. Forty-three out of 298 cases of CRCs (14.4%) showed abnormal staining pattern for mismatch repair proteins with a majority (65.1%) showing single hMLH1 loss. Tumours with mismatch repair defect (MMR-d) were frequently found at the right side of colon (p<0.001), poorly differentiated carcinomas (p<0.001), produced more mucin (p=0.007), exophytic growth (p=0.007) and were bigger (p=0.002) than tumours with no mismatch repair defect. Immunohistochemical stains for mismatch repair proteins could be done in local laboratories on these selected cases before referring for the expensive molecular test.

Cerebrospinal fluid rhinorrhoea secondary to amyloidosis of the sphenoid sinus

Amyloidosis of the skull base is a rare entity. A patient with localized amyloidosis of the sphenoid sinus presented at our institution with cerebrospinal fluid rhinorrhoea. Endoscopic excision of the lesion and multilayered obliteration of the sphenoid sinus resolved the symptoms.

An immunohistochemical and molecular study of gastrointestinal stromal tumours

Gastrointestinal stromal tumour (GIST) is a rare but most common mesenchymal tumour in the gastrointestinal tract. Although GIST research has been carried out extensively worldwide, it has yet to be studied in Malaysia. To establish the immunohistochemical expression pattern of CD117 (c-KIT), CD34, S-100 and Desmin, the incidence of c-KIT and PDGFRA genes mutation in GISTs, and correlate it with clinicopathological parameters. Eleven clinically diagnosed GISTs were stained for CD117, CD34, Desmin and S-100 protein by immunohistochemical technique, and c-KITand PDGFRA gene mutations were studied by PCR-CSGE-DNA sequencing method. All GISTs (7 cases) stain positive for CD117, and co-expressed CD34. None of these cases express Desmin, and only one expressed S-100 protein focally. Fifty-seven percent (4/7 cases) of GIST harboured mutations at exon 11 of c-KIT gene, and they were all high risk and malignant cases. No mutation was detected at exons 9, 13 and 17 of KIT gene, and exons 12 and 18 of PDGFRA gene. Immunohistochemistry using a panel of antibodies shows consistent pattern of CD117 and CD34 expression in GIST, and mutational study may be a useful prognostic marker for kinase inhibitor treatment of GIST.

The pattern of CD15, CD30 and Bcl-2 expression in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is a heterogenous entity. The pattern of CD15, CD30 and Bcl-2 expression is not well documented, especially in local population. We investigated 67 consecutive cases of DLBCL by immunohistochemistry on paraffin-embedded tissue. The male to female ratio was 1.2:1 with median age of 55 years, and more common nodal than extranodal in presentation. Only 3 of 67 cases expressed CD15. In addition, three cases showed weak membrane staining for CD30. Only one of these three cases was noted to have co-expression of CD15 and with occasional tumour cells showing weak CD30 expression. Bcl-2 protein was expressed in 43 of 67 (64%), more frequently in nodal than in extranodal tumours. In conclusion, CD15 and CD30 expressions are infrequent in DLBCL, and co-expression is rare. Bcl-2 protein expression is common in DLBCL.

p53 alterations in sequential biopsies of Asian follicular lymphoma: a study of immunohistochemical staining pattern and gene mutations by PCR-SSCP in paraffin-embedded tissues

AIM

Tumour suppressor gene p53 is a common target in carcinogenesis, reported to be altered and functionally inactive in 70% of human cancers. Although p53 mutations are less commonly present in haematological malignancies when compared with other solid tumours, they have been reported in histological transformation of follicular lymphoma. We aimed to investigate the frequency of p53 gene alterations in paraffin-embedded tissue using commercially available PCR-SSCP, and to correlate the results with P53 protein expression by immunohistochemistry.

METHODS

Surgical samples from seven patients with a total of 17 sequential biopsies were retrieved for the study of p53 gene expression using immunohistochemical stain, and gene status by PCR-SSCP for exons 5-8. The tumours were graded according to the WHO classification criteria. P53 was distinctly over-expressed in five transformed higher grade biopsies, and all except one showed electrophoretic mobility shift in PCR-SSCP analysis. Sequencing analysis revealed single nucleotide substitutions in three of four of these high-grade transformed cases with band shift (75%), whereas some other studies reported a lower frequency of 25-30%, and mobility shift result was found to correlate with P53 expression. Lower grade tumours without P53 over-expression did not demonstrate band shift, and sequencing analysis did not reveal mutations.

CONCLUSIONS

We demonstrated the feasibility of adopting PCR-SSCP for screening of p53 mutations in archival tissue samples in this study, and there is a strong correlation of p53 gene over-expression and mutation events in high-grade transformed tumours.

The pattern and frequency of t(14;18) translocation and immunophenotype in Asian follicular lymphoma

AIMS

Follicular lymphoma is frequently associated with t(14;18)(q32;q21) translocation. This study was undertaken to determine the pattern of Bcl-2, CD10 and Bcl-6 expression in relation to t(14;18) translocation in follicular lymphoma from a cohort of a multi-ethnic Asian population.

METHODS AND RESULTS

Sixty-two cases of follicular lymphoma were retrieved for immunohistochemistry, and t(14;18) translocation analysis by polymerase chain reaction and fluorescent in-situ hybridization techniques. Bcl-2 expression was present in 74% of the cases. CD10 expression was also relatively low (61%), with decreasing frequency of expression in high-grade tumours. Bcl-6 protein was expressed in most of the tumours (88%) regardless of the tumour grade. The t(14;18) translocation was detected in 46 cases (74%) with an extremely high rate of t(14;18) translocation in ethnic Indian cases (100%).

CONCLUSION

The frequency of t(14;18) translocation in this series of follicular lymphomas was higher when compared with previous Asian reports, but in accordance with European and North American findings. CD10 expression is strongly associated with a t(14;18) translocation event, but the overall CD10 expression was relatively low, possibly due to the high proportion of high-grade tumours in the series. t(14;18) translocation was not associated with Bcl-2 or Bcl-6 expression.

P53 expression in colorectal carcinoma: the University of Malaya Medical Centre's experience

Loss of P53 function is regarded as one of the critical steps in colorectal carcinogenesis. This study determines the P53 expression pattern of colorectal carcinoma in a cohort of 116 local patients. There was no significant relationship between overexpression of P53 with tumour stage (p=-0.209, chi square test) and grade (p=0.877, chi square test). Survival analysis using Kaplan-Meier procedure did not show significant relationship between P53 positivity with overall recurrence-free and survival outcome (p=0.3322 and 0.921 respectively; log rank test). Long-term follow-up may give a better evaluation on the prognostic value of P53 overexpression in colorectal carcinoma.

Spectrum of malignant lymphoma in Queen Elizabeth Hospital, Sabah

Lymphomas, ranked twelve among all cancers world-wide in the 1990s, in which it is more prevalent in males compared to females. A previous study on lymphomas in East Malaysia for a period of 3 years from 1981-1983 showed that the pattern of lymphomas conformed to the general pattern observed in Asia. Current study reviews lymphoma cases from the Department of Pathology, Queen Elizabeth Hospital, Sabah between 1997 and 1999, with the aim of investigating if the spectrum and pattern in Sabah has since changed, a decade later. A total of 91 confirmed lymphoma cases were phenotyped with a panel of antibodies and classified using the new WHO proposed list of lymphoid neoplasms. The 1981-1983 series was reviewed and cases reclassified accordingly for comparison. There are 83 (91.2%) NHL and 8 (8.8%) HL cases in this series, a ratio of NHL to HL of 9:1. Of the 83 cases of NHL, 66 (79.5%) were confirmed B-cell type, 13 (15.7%) T-phenotype, 1(1.2%) null cell type and one case unclassified. Diffuse large B-cell lymphoma is the most prevalent, (65.1%), followed by Burkitt's lymphoma and follicular lymphoma, (10.6%) each. Lymphoma pattern concurs with the previous series from Sabah, with higher prevalence of diffuse large cell lymphoma and lower incidence of follicular lymphoma and HL, as seen elsewhere in Asia. There is an overall increase in the number of cases of NHL in the 1990s. However, the proportion of T-NHL is reduced when compared to the series in the 1980s.

Nasal and nasal-type natural killer (NK)/T-cell lymphoma: immunophenotype and Epstein-Barr virus (EBV) association

Epstein-Barr virus (EBV) is believed to have a pathogenic role in lymphomas of the upper-aerodigestive tract. This study aims to elucidate the virus association pattern in nasal and nasal-type NK/T-cell lymphomas, and in sequential biopsies of these tumours. A total of 31 cases of previously diagnosed as lethal midline granuloma. Stewart's granuloma, nasal T-cell non-Hodgkin's lymphoma (T-NHL) and NK/T-cell lymphomas from all anatomical sites were retrieved from the files for the study. Reviews of these cases confirm 8 nasal T-NHL, 19 nasal and 4 extranasal lymphomas of NK/T-cell phenotype from 10 Malays, 18 Chinese, 2 Indian and 1 Kadazan. The male: female ratio was 2.4: 1. All T- and NK/T-cell lymphomas strongly expressed TIA-1 and 63% expressed CD2. The majority of NK/T-cell lymphoma occurred in Chinese (13/23), of which 12/13 (92%) of these cases were associated with EBV. Of the 15 nasal and 9 tonsillar B-cell lymphomas included for a comparison study, only 3 (20%) of the nasal cases were associated with EBV (1 male Chinese, 1 female Chinese and 1 male of other ethnic group). Eight cases of NK/T-cell tumours with sequential biopsies show persistence of EBV, irrespective of the interval and sites of subsequent presentations. This study confirms the cytotoxic nature of NK/T-cell tumour and that EBV is strongly associated with the disease regardless of the anatomical site of presentation and ethnicity. However, nasal and paranasal lymphomas of all phenotypes appear to show higher predilection of EBV association in the ethnic Chinese when compared to non-Chinese.

Feasibility of T-cell receptor gamma (TCRgamma) gene rearrangement on formalin-fixed, paraffin-embedded tissues by PCR assays

INTRODUCTION

T- and B-lymphocytes are involved in recognition of foreign antigen by the specificity of their surface T-cell receptor and immunoglobulin, generated by gene rearrangement. Each T- and B-lymphocyte carries unique rearranged TCR or immunoglobulin gene, which has been applied to detect clonal from non-clonal T- and B-cell proliferation.

METHODS

Paraffin-embedded biopsy tissues of 85 T-, 24 B-cell non-Hodgkin's lymphomas (NHL) of various subtypes, and seven reactive lymphoid hyperplasia were retrieved from the archives for determining the feasibility of TCRgamma gene rearrangement analysis by PCR assays in our laboratory. DNA was extracted by Proteinase K digestion. The analyses were performed by five PCR assays, and analysed on polyacrylamide gel.

RESULTS

Clonal TCRgamma gene rearrangement was demonstrated in 69/85 (81.2%) of the cases. Selective rearrangement of specific Vgamma segment was observed, especially in peripheral T-cell lymphoma-unspecified and nasal NK/T-cell lymphoma. Clonal TCRgamma rearranged band was also demonstrated in 4/24 (16.7%) and 2/7 (28.6%) of B-NHL and reactive lymphoid tissues respectively.

CONCLUSION

PCR assays were able to demonstrate clonal TCRgamma gene rearrangement in a high proportion of T-NHL. However, the PCR results should be interpreted carefully. A neoplasm should only be considered as T-cell type if it does not express any B-cell marker because TCRgamma is not lineage specific as shown by the presence of clonal TCRgamma gene rearrangement in B-NHL. Hence, the results for TCR gene rearrangement should always be interpreted in conjunction with histology and immunophenotyping.

The immunophenotypic patterns of follicle centre and mantle zone in Castleman's disease

BACKGROUND

Castleman's disease is an uncommon disease and the histopathogenesis is poorly understood. This study aims to investigate their clinicopathological and immunophenotypic profile.

MATERIALS AND METHODS

Castleman's disease was reconfirmed in biopsy tissue from 10 patients in a period of 17 years. Immunohistochemical staining was performed on the archival materials, with antibodies to lymphoid antigens and oncogene products, Bcl-6 and Bcl-2. Six reactive hyperplastic lymph nodes and three tonsils were used for comparative study of the phenotypic expression.

RESULT

There were three cases of plasma-cell and seven of hyaline-vascular variant. The ages of patients ranged from eight to 60 years (median 30 years). The three patients with plasma-cell variant were older, all females. Two of the plasma-cell variant had multicentric lesions associated with systemic disease. All patients with hyaline-vascular variant had localised disease. Atrophic follicle centres were present in all the diagnostic tissue of both subtypes, with loss of Bcl-6 follicular centre B-cells and presence of relatively few CD57 T-cells. These follicle centres stained strongly with anti-CD21. In the mantle zone, CD5 expression was observed in only two cases and Bcl-2 expression similar to reactive follicles was present in six.

CONCLUSION

Loss of Bcl-6 B-cells in the atrophic follicle centres, characteristic CD21 network patterns, low rate of CD5 and Bcl-2 expression in the mantle-zone lymphocytes are present in both variants of Castleman's disease, differ distinctly from reactive follicles. The phenotypic similarity in these two variants suggests possibility of closely related pathogeneses.

TARC, a CC chemokine, is frequently expressed in classic Hodgkin's lymphoma but not in NLP Hodgkin's lymphoma, T-cell-rich B-cell lymphoma, and most cases of anaplastic large cell lymphoma

Thymus and activation-regulated chemokine (TARC) has been identified as a lymphocyte-directed CC chemokine that attracts activated T-helper type 2 (Th2) cells in humans. Recent studies showed that the T cells surrounding Reed-Sternberg cells in Hodgkin's lymphomas (HL) are Th2 type. Anaplastic large cell lymphomas (ALCL), T-cell-rich B-cell lymphoma (TCRBCL) can mimic HL in some instances. This study aimed to establish the pattern of TARC expression in these diseases. Immunohistochemical stain using a polyclonal goat anti-human antibody to TARC was performed on 119 cases of confirmed HL; 99 were classical type (43 mixed cellularity, 43 nodular sclerosis, 5 lymphocyte depleted, 4 lymphocyte rich, 4 unclassifiable) and 20 lymphocyte predominant HL. Additional 27 ALCL (9 T-, 18 null-cell phenotype), 16 T-cell and 8 B-cell non-Hodgkin's lymphoma (NHL) were studied. A total of 85.8% of the classical HL, one case of ALCL, and one case of large cell B-cell lymphoma with anaplastic morphology showed positive TARC expression in the tumor cells. The expression was paranuclear and/or diffuse in the cell cytoplasm. The tumor cells in all cases of lymphocyte predominant HL, TCRBCL, null ALCL, and T-NHL did not express TARC. The high frequency of TARC expression in the Reed-Sternberg cells of classical HL may explain the characteristic T-cell infiltrate in this disease. The absence in other types that may be morphologically similar indicates that staining for TARC may aid in differential diagnosis.

Host ethnicity influences non-Hodgkin's lymphoma subtype frequency and Epstein-Barr virus association rate: the experience of a multi-ethnic patient population in Malaysia

AIMS

The pattern of malignant lymphoma is known to vary in different populations. This study aims to elucidate the effect of ethnicity on subtype frequency of non-Hodgkin's lymphoma and EBV association rate.

METHODS AND RESULTS

A total of 232 reconfirmed lymphoma cases in Malaysian patients were retrieved from the archives in the Department of Pathology, University Hospital, Kuala Lumpur. There were 24 (10%) Hodgkin's and 208 (90%) non-Hodgkin's lymphomas, 173 of the latter were in adult group (aged > or = 15 years). The ethnic composition were 41 Malays, 107 Chinese, 21 Indians and four none of the above. A male : female ratio of 2.4 : 1 was observed. Complete immunohistochemical studies in 158 cases revealed 36 (23%) T-cell, 121 (76%) B-cell and one (1%) null-cell phenotype. Seventy-five percent of the T-cell lymphomas were peripheral T/NK-cell types. Among the classifiable lesions, low-grade/indolent lymphomas constituted 17%: 2% were the lymphocytic subtype and 10% were follicular lymphomas. Approximately one-third of the follicular lymphomas occurred in Indian patients. The largest group of high-grade lymphoma was diffuse large B-cell type (46%), followed by peripheral T/NK-cell (18%). A predominance of NK/T-cell lymphomas occurred in Chinese (5/7), and all were EBV associated. Burkitt's lymphoma accounted for 5% (eight cases), all were Chinese males, with a 38% EBV-association rate. The frequency of EBV-associated B-cell lymphoma is three times more common in Chinese than Malays. The EBV positivity rate among lymphomas in ethnic Malay, Chinese and Indian patients was 5%, 15% and 22%, respectively, and in T- and B-cell lymphomas was 36% and 7%, respectively.

CONCLUSIONS

This Malaysian series reveals differences in the subtype frequencies of non-Hodgkin's lymphomas and EBV association rate amongst patients of various ethnic groups residing in the same environment.

Clinical drug-resistant nodular sclerosing Hodgkin's lymphoma is associated with decreased bcl-2 expression in the surrounding lymphocytes and with increased bcl-2 expression in the Reed-Sternberg cells

Identification of patients with Hodgkin's lymphoma who are primary refractory to chemotherapy will have great impact on treatment planning. Several studies have indicated that up-regulation of the bcl-2 proto-oncogene expression in non-Hodgkin's lymphoma can cause resistance to chemotherapeutic drugs. For this reason we investigated the relationship between expression of bcl-2, the pro-apoptotic protein Bax and MIB-1 with clinical drug-resistance in Hodgkin's lymphoma.

METHODS AND RESULTS

Seven patients with nodular sclerosis Hodgkin's lymphoma under 40 years of age, who failed to achieve complete remission upon primary chemotherapy and 10 matched patients who did achieve complete response were selected from the Eindhoven Cancer Registry. Tissue sections from both groups of patients were stained for bcl-2, Bax and MIB-1. In the non-responding patients Reed-Sternberg cells expressed bcl-2 more frequently using a cut-off point of <25% to indicate negative cells (P = 0.04), whereas no differences were observed in the expression of Bax and MIB-1. In non-responding patients the lymphocytes surrounding Reed-Sternberg cells expressed bcl-2 less frequently (P = 0.002), using a cut-off point of < 25%, whereas no difference was observed in the expression of Bax and MIB-1.

CONCLUSION

A high percentage of Reed-Sternberg cells expressing bcl-2 protein and a low expression of bcl-2 proteifi in the surrounding lymphocytes is associated with treatment-failure, and subsequent poor survival in young patients with nodular sclerosing Hodgkin's lymphoma. These results need further validation in larger studies.

Bone marrow and peripheral blood changes in non-Hodgkin's lymphoma

BACKGROUND

47 patients with non-Hodgkin's lymphoma (NHL) were studied retrospectively to determine their marrow and blood changes at diagnosis.

METHODS

The blood counts, blood films, marrow smears, trephine and tissue biopsies of patients at diagnosis were reviewed. The scheme proposed by the International Lymphoma Study Group (REAL) was utilised for lymphoma subclassification.

RESULTS AND CONCLUSION

21.3% had lymphoblastic lymphoma, 21.3% had peripheral T-cell lymphoma (unspecified), 29.8% had diffuse large B-cell NHL, 10.6% had Burkitt's lymphoma and 17% had others. The incidences of anaemia, one or more abnormal counts, lymphocytopenia, increased marrow reticulin and marrow eosinophilia at diagnosis were 66%, 85.1%, 41.3%, 40.9% and 44.7% respectively. Marrow involvement was present in 46.8% of the patients, with diffuse infiltration noted in 71.4% of these cases. Abnormal counts and anaemia were common in all the NHL subtypes. In lymphoblastic lymphoma, the common haematological abnormalities were peripheral atypical lymphocytes and diffuse marrow involvement. In peripheral T-cell lymphoma (unspecified), common features were peripheral lymphocytopenia, increased marrow reticulin and eosinophilia. In diffuse large B-cell NHL, peripheral lymphocytopenia, peripheral myeloid precursors and/or nucleated red cells and marrow involvement were common. In Burkitt's lymphoma, diffuse marrow involvement and eosinophilia were common. No significant differences were noted between most of the haematological parameters of B and T-NHLs. In comparison with other reports, we recorded higher overall incidences of anaemia and diffuse marrow involvement, and a lower incidence of marrow infiltration in peripheral T-cell lymphoma (unspecified).

Spectrum of malignant lymphomas in Klang Hospital, a public hospital in Malaysia

BACKGROUND

Lymphoma is a relatively common group of neoplasms diagnosed in hospital practice. This study aims to elucidate the pattern of this disease encountered in a public service hospital of the Ministry of Health, Malaysia.

MATERIALS AND METHODS

A total of 98 biopsies from 92 patients were retrieved from the archives of Klang General Hospital, from January 1993 to June 1999. The histopathology of these biopsies were reviewed by two pathologists, and confirmed cases were sub-classified according to the WHO proposed scheme. Immunohistochemical staining with a panel of lymphoid antibodies was performed in aid of sub-typing. All cases were screened for Epstein-Barr virus association by in-situ hybridisation technique.

RESULTS

15 biopsies were excluded from further analysis due to inadequate material for further study or diagnosed as non-lymphoma. The remaining 83 biopsies were from 80 patients. 52 were males and 28 females. The male: female ratio was 1.9:1. There were 64 Malays, 4 Chinese and 12 Indians. The ages of patients ranged from 3 to 86 years with a mean age of 50.5 years. 73.8% of the diagnostic materials were nodal tissue. Fourteen patients had Hodgkin's lymphomas (HL), 6 being mixed-cellularity, 4 nodular-sclerosis, 1 lymphocyte-rich, 2 lymphocyte-depleted, 1 lymphocyte-predominant, and 66 had non-Hodgkin's lymphomas (NHL). The HL: NHL ratio was 1:4.7. Of the 66 cases of NHL, 9 (13.6%) were T- and 57 (86.4%) B-cell types. The most common NHL encountered was diffuse large B-cell type. Follicular-lymphoma constituted 16.7% of these NHL. 77.8% of T-NHL and 10.5% of B-NHL was EBV associated. Double staining of EBER with CD20 and EBER with CD3 in the T-NHL cases showed that in a majority of the cases, EBER-positive large cells did not express the T- or B- cell antigen.

CONCLUSION

There is a relatively small proportion of T-cell lymphoma in this series of Asian patients. The reason is thought to be the lower utilisation rate of this hospital service by ethnic Chinese, as reflected by the hospital admission data.

Pattern of lymph node pathology in a private pathology laboratory

Lymph node excision biopsy is commonly carried out for the investigation of lymphadenopathy. The objective of this study is to elucidate the pattern of nodal pathology seen in a private pathology practice. A total of 137 nodal biopsies for primary investigation of nodal enlargement were retrieved from the files in a private diagnostic pathology laboratory in the year 1997. Lymph nodes excised for cancer staging were excluded from this study. The histology was reviewed based on H&E stained sections, and with additional histochemical and immunoperoxidase stains when deemed necessary. Cases of malignant lymphomas were sub-classified with the aid of further immunophenotyping using a panel of monoclonal and polyclonal lymphoid antibodies. One case was excluded from this study due to inadequate tissue for further assessment. There were 58 males and 78 females, giving a ratio of 1:1.3 in the remaining 136 cases. They consisted of 13 Malays (M), 108 Chinese (C), 14 Indians (I) and 1 other ethnic group (O). The ratio of M:C:I:O was 1:8.3:1.1:0.1. The majority of the cases were in the age range of 20 to 50 years. The pathology consisted of 17 (12.5%) malignant lymphomas [6 Hodgkin's lymphoma, 11 non-Hodgkin's lymphoma], 35 (25.7%) metastatic carcinomas, 45 (33.1%) reactive hyperplasia, 19 (13.9%) tuberculosis, 11 (8.2%) Kikuchi's disease and 9 (6.6%) others (Castleman's disease 2, cat scratch disease 2, Kimura's disease 1, sarcoidosis 1, non-specific lymphadenitis 3). All categories of nodal disease showed approximately similar ratio of ethnic and gender distribution as above, except for Kikuchi's disease, for which 100% of the patients were female. The most common site of biopsy was from the head and neck region, particularly the cervical group of nodes. The most common nodal pathology seen in the private laboratory was reactive hyperplasia, followed by metastatic carcinoma. Malignant lymphoma constituted only 12.5% of the cases.

X-chromosome inactivation analysis of isolated Reed-Sternberg cells in nodular sclerosing Hodgkin's disease

In spite of several studies of immunoglobulin (Ig) gene rearrangements in whole Hodgkin's disease (HD) tissues and in isolated single Reed-Sternberg (RS) cells, the issue of clonality of the RS cell in HD remains incompletely resolved. Analysis of X-chromosome inactivation patterns (XCIPs) can be used to determine whether cell populations are clonal in origin. By PCR amplification of the human androgen receptor (HUMARA) loci using nested primers, we have studied XCIPs in six cases of HD of the nodular sclerosing (NS) subtype in which individual RS cells were isolated by micromanipulation from formalin-fixed, paraffin-embedded tissue sections immunostained with CD30 or CD15. In order to assess whether a clonal population of RS cells might be present in NSHD tissues, we compared the XCIPs obtained from whole NSHD tissues with those obtained from single RS cells harvested from the same tissues. Whole tissues from all six cases of NSHD showed balanced HUMARA allelic patterns, whereas an average of 83% (range 77-91%) of single RS cells from each of the six tissues expressed the same high- or low-molecular weight allele, suggesting that a clonal population of RS cells was likely to be present in each case. These data are consistent with the presence of a clonal population of RS cells in NSHD tissues.

The pattern of lymphoma in east Malaysian patients as experienced in the University Hospital, Kuala Lumpur

Lymphoma is a highly heterogeneous group of malignant disease. This study aimed to elucidate the pattern of lymphoma in the East Malaysian patient population. 107 cases of confirmed lymphomas from East Malaysian biopsy material were retrieved from the files of the Department of Pathology, University of Malaya, in the 3-year period between 1981 to 1983. With the use of a panel of lymphoid antibodies, the disease was sub-classified using the Rye classification for Hodgkin's lymphoma (HL) and the REAL classification for non-Hodgkin's lymphoma (NHL). All of the cases were tested for the presence of the Epstein-Barr virus by EBER-ISH. There were 11 (10.3%) HL, 80 (74.7%) B-NHL and 16 (15%) T-NHL. The HL:NHL ratio was 1:9. The most common tumour in children was Burkitt's lymphoma 7/13 (53.8%). In the adult group, there were 72/94 (76.6%) B-NHL ¿diffuse large cell type 51 (of which 2 were CD30+), Burkitt's lymphoma 8, follicular lymphoma 5, low grade MALT 2, mantle cell type 1 and not otherwise specified due to poor morphology 5¿, 13/94 (13.8%) T-NHL and 9/94 (9.6%) HL. Of the 9 adult HL, the most common subtype was nodular sclerosis (6, 66.7%). The EBER positive rate in classical HL, T-NHL, BL and B-NHL were 33.3%, 56.3%, 60.0% and 3.1% respectively. In conclusion, the spectrum of lymphoma seen in East Malaysia was rather similar to West Malaysia except for the very low prevalence of peripheral T-cell lymphoma (PTCL) in Sarawak (3.3%).

Does Helicobacter pylori infection affect gastric emptying in patients with functional dyspepsia?

The objectives of the study were first, to determine if gastric emptying was altered in patients with functional dyspepsia with and without Helicobacter pylori infection compared with normal healthy volunteers; and second, to determine if there were further alterations in gastric emptying when the infection was eradicated. Gastric emptying was measured using a 99mtechnetium radiolabelled solid meal and gastric emptying time was measured as t1/2, viz. time taken for half the radiolabelled meal to be emptied from the stomach. The mean gastric emptying time for H. pylori-positive patients (n=20) was 56.4+/-24.8 min; H. pylori-negative patients (n=19) 67.8+/-31.8 min; and normal controls (n=20) 58.8+/-18.8min. No significant difference was obtained between the groups (ANOVA; P=0.348). Thirteen of 18 H. pylori-positive patients successfully eradicated the infection following treatment with omeprazole 40 mg o.m. and amoxycillin 500 mg t.d.s. for 2 weeks. The mean difference in the gastric emptying time before and after H. pylori eradication was 23.9+/-13.2 min (P= 0.556). There was no significant difference in the frequency of specific dyspeptic symptoms as well as the overall mean symptom score between the H. pylori-positive and -negative patients. Gastric emptying was not different between patients with functional dyspepsia and normal controls. Helicobacter pylori infection does not appear to affect gastric emptying in patients with functional dyspepsia.

The pattern of Ki-67 and bcl-2 expression in lymphoid malignancies

The International Working Formulation divides non-Hodgkin's lymphoma (NHL) into three grades: low, intermediate and high. This grading system implies rate of tumour growth and hence prognosis. Ki-67 antigen is a proliferation-related nuclear antigen and bcl-2 oncogene product is known to inhibit apoptosis. This study aimed to determine the pattern of expression of Ki-67 antigen and bcl-2 oncoprotein in various grades of NHL. Paraffin-embedded tissues from 42 cases of NHL (7 low, 15 intermediate, 20 high grade) were retrieved from the files of the Department of Pathology, University of Malaya. Ki-67 antigen and bcl-2 oncoprotein were detected using immunohistochemistry. The percentage of positively stained neoplastic cells was determined by semi-quantitative estimation and given scores ranging from 0 to 6. Partition chi square test demonstrated the association of Ki-67 antigen expression and histological grade (p = 0.007). There was no significant difference in Ki-67 antigen expression between intermediate and high grade malignant lymphomas (p = 0.28), whereas significant difference was demonstrated between low and intermediate/high grade tumours (p = 0.003). Bcl-2 oncoprotein expression in the neoplastic cells varied widely within the three histological grades. Statistical analysis showed no association between the expression of bcl-2 oncoprotein and histological grade (p = 0.25). Ki-67 immunostaining is therefore a useful adjunct to histological grading of NHL.

Epstein-Barr virus (EBV) and Hodgkin's disease in a multi-ethnic population in Malaysia

The Epstein-Barr virus (EBV) has been implicated as a contributing factor in the development of Hodgkin's disease. Western cases of Hodgkin's disease have shown the presence of EBV in Hodgkin and Reed-Sternberg cells in approximately 50%. We studied a total of 100 consecutive cases of Hodgkin's disease from Malaysia, with the aim to elucidate its association with EBV in a multi-ethnic Asian population. Of 34 patients (34%) less than 15 years of age (childhood), 25 had classical Hodgkin's disease (eight nodular sclerosis, 16 mixed cellularity, one lymphocyte depleted) and nine had lymphocyte predominance Hodgkin's disease. Of the 66 from patients aged 15 years and above, 33 had nodular sclerosis, 24 mixed cellularity, two lymphocyte depleted, one unclassifiable and six lymphocyte predominance Hodgkin's disease. The ethnic distribution of classical Hodgkin's disease was: Malay 23, Chinese 32 and Indian 30 (Malay:Chinese:Indian = 1:1.4:1.3), and the ethnic distribution in the 15 cases of lymphocyte predominance Hodgkin's disease was: Malay four, Chinese 10 and Indian one. Taking into account the ethnic distribution of the general population and of hospital admissions, there appears to be a significant predilection of classical Hodgkin's disease cases in ethnic Indian compared to non-Indian patients (chi-squared test, 0.025 > P > 0.01). Eighty-one cases were tested for the presence of EBV by in situ hybridization for EBV encoded RNA, and 57 cases by immunostaining for EBV latent membrane protein 1. In the younger age group, all except one of the 15 cases (nine mixed cellularity, six nodular sclerosis) showed the presence of EBV (93%). In the older age group, EBV was detected (52%) in the following proportion: 6/27 nodular sclerosis, 19/22 mixed cellularity, 1/2 lymphocyte depleted, 1/1 unclassifiable. None of the 14 cases of lymphocyte predominance Hodgkin's disease showed the presence of EBV in the Hodgkin and Reed-Sternberg cells. The findings suggest a strong association of EBV with Hodgkin's disease in Malaysians (41/67, 61%), in particular childhood cases (93%). In adults, the association with EBV is significantly higher in the mixed cellularity subtype (86%) compared with the nodular sclerosis subtype (22%).

Reinfection and duodenal ulcer relapse in south-east Asian patients following successful Helicobacter pylori eradication: results of a 2-year follow-up

OBJECTIVES

To determine the reinfection rate of Helicobacter pylori and duodenal ulcer relapse rate in a group of patients followed up long term.

DESIGN

Prospective study.

PATIENTS AND METHODS

Patients were followed up endoscopically at 3, 6, 12 and 24 months after successful H. pylori eradication and duodenal ulcer healing. H. pylori status was determined by culture, rapid urease test, Gram's stain of a fresh tissue smear and histological examination of antral biopsies and rapid urease test and histological examination of corpus biopsies.

MAIN OUTCOME MEASURES

Duodenal ulcer healing, H. pylori reinfection.

RESULTS

Thirty-eight patients with duodenal ulcer disease (35 active, 3 healed) had successfully eradicated H. pylori following treatment with omeprazole/amoxycillin (n = 11), omeprazole/amoxycillin/metronidazole (n = 16) and colloidal bismuth subcitrate/ amoxycillin/metronidazole (n = 11). All patients with active duodenal ulcer had healed ulcers at the end of therapy. Thirty-five of 38 patients were seen according to schedule up to 2 years; two patients were seen up to 12 months and one up to 6 months only. Reinfection with H. pylori was not recorded in any of our patients. Shallow duodenal ulcers were noted in three patients at 1-year follow-up, two of whom admitted to taking non-steroidal anti-inflammatory drugs (NSAIDs); H. pylori status was negative in all three. Subsequent follow-up revealed spontaneous healing of the ulcers in all three patients. At 2 years, one patient whose H. pylori status was negative had recurrence of duodenal ulcer. All of the three patients who defaulted subsequent to follow-up were negative for H. pylori and had healed ulcers on follow-up endoscopy at 6 and 12 months.

CONCLUSION

Reinfection rate with H. pylori was zero in a group of South-East Asian patients who had successfully eradicated the infection. Duodenal ulcer relapse was also low (2.9%) in this group of patients at 2 years.

Helicobacter pylori eradication with short-term therapy leads to duodenal ulcer healing without the need for continued acid suppression therapy

OBJECTIVE

To determine whether duodenal ulcers continue to heal following successful Helicobacter pylori eradication with short-term eradication therapy without further acid suppression therapy.

METHODS

Patients with endoscopically proven duodenal ulcers who were H. pylori positive were randomized to receive omeprazole 40 mg each morning and clarithromycin 500 mg three times daily or famotidine 40 mg twice daily and clarithromycin 500 mg three times daily for 2 weeks. No acid-suppressing agents nor ulcerhealing drugs such as bismuth compounds or sucralfate were prescribed after that. Patients were re-examined endoscopically at week 2 at the end of treatment, and at week 6, 4 weeks after the completion of treatment.

RESULTS

Thirty of 44 (68.2%) patients from both treatment arms, in whom the bacteria were subsequently noted to have been eradicated, had healed ulcers at week 2; at Week 6, 42 of 44 (95.5%) were noted to have healed ulcers without further acid-suppressing or ulcer-healing treatment.

CONCLUSION

Although a short-term acid-suppressing treatment is insufficient to heal ulcers, where an important putative factor such as H. pylori is eliminated, the ulcer healing process continues without further need for acid-suppressing or ulcer-healing agents.

Prolonged treatment with omeprazole does not improve the eradication rate of Helicobacter pylori infection--a short report [corrected]

Omeprazole has been shown to have a suppressive effect on Helicobacter pylori. The aim of this study was to determine if prolonged treatment with omeprazole would result in a higher eradication rate than short course treatment. Twenty patients with endoscopy proven duodenal ulcers and unequivocal evidence of Helicobacter pylori (HP) infection based on culture, histology, urease test and Gram's stain of a fresh tissue smear were treated with omeprazole 40 mg om for 2-4 weeks. Following ulcer healing, patients received either maintenance omeprazole 20 mg om or placebo for up to one year. All 20 patients had healed ulcers following a 2-4 week course of omeprazole 40 mg om.. All were negative for HP at the end of treatment. Thirteen patients received short course therapy with omeprazole only, followed by placebo. On follow-up endoscopy at 3 months, only one of 13 (7.7%) had eradicated the bacteria. Seven patients received maintenance treatment with omeprazole 20mg om for one year. Following completion of treatment, patients were followed up at 1, 3 and 6 months. Only one of 7 (14.3%) patients had eradicated the infection on long term follow-up. The eradication rates of HP with both short and long course omeprazole monotherapy were low.

14C-urea breath test: a useful non-invasive test in the diagnosis of Helicobacter pylori infection

Sixty-three breath samples were collected from patients who underwent a 14C-urea breath test. Following ingestion of a radiolabelled 14C-labelled urea solution, breath samples containing 14C-labelled carbon dioxide were trapped in a solution containing hyamine hydroxide. Samples were then counted in a liquid scintillation counter. Breath samples were collected at 2, 15, 20, 25 and 30 minutes following ingestion of the urea solution. The presence or absence of Helicobacter pylori (HP) infection was determined on the basis of endoscopic biopsy tests which included culture, histological examination, rapid urease test and a gram stain of a fresh tissue smear. Thirty-two HP positive and 31 HP negative samples were collected. The mean counts at 15, 20, 12 and 30 minutes time points were: 4413, 4458, 4109 and 3795 dpm respectively for the positive samples and 1275, 877, 690 and 565 dpm respectively for the negative samples. Based on a cutoff value (mean of the negative samples + 3 standard deviations) for every time point, HP positive and negative samples could be clearly differentiated giving a sensitivity and specificity of 100%. The 14C-urea breath test is a reliable and convenient diagnostic test for H. pylori.

Epstein-Barr virus (EBV) in Malaysian upper-aerodigestive-tract lymphoma: incidence and sub-type

Epstein-Barr virus (EBV) type B, a less potent transformer of B lymphocytes than type A, has rarely been detected in EBV-associated neoplasms except in AIDS-related lymphomas, in which about 50% of the cases contained this sub-type. In this study we analyzed the association of EBV and the distribution of virus sub-types in Asian non-Hodgkin's lymphoma (NHL) of the upper aerodigestive tract. We studied archival material of 29 NHL cases from Malaysia. B- and T-cell associated antigens were demonstrated by immunohistochemistry, and EBV early RNA EBER-1 was demonstrated using the RNA in situ hybridization technique. EBV was detected in the majority of tumour cells in 11/13 T-NHL but in only 1/16 B-NHL. EBV was sub-typed by single-step polymerase chain reaction of the EBNA-2 gene. This was successful in 9/10 cases of EBER-1-positive tumours and all contained type-A virus only. Our results showed a preponderance of T-cell lymphoma of the upper aerodigestive tract in the ethnic Chinese group of Malaysian patients, and EBV was strongly associated with T-NHL but not with B-NHL. Our results suggest that type-A EBV is the prevalent sub-type in Asian NHL of the upper aerodigestive tract, similarly to findings in Asian nasopharyngeal carcinoma.

Identification of potential hot spots in the carboxy-terminal part of the Epstein-Barr virus (EBV) BNLF-1 gene in both malignant and benign EBV-associated diseases: high frequency of a 30-bp deletion in Malaysian and Danish peripheral T-cell lymphomas

In this study, we have sequenced the C-terminal part of the Epstein-Barr virus (EBV)-BNLF-1 gene encoding for the latent membrane protein-1 from tissues of EBV-positive Danish Hodgkin's disease (HD) and of Danish and Malaysian peripheral T-cell lymphomas (PTLs) and from tonsils of Danish infectious mononucleosis (IM). Our study showed that some of the 7 single-base mutations and the 30-bp deletion previously detected between codons of amino acid 322 and 366 in the BNLF-1 gene of the nasopharyngeal carcinoma cell line CAO were present in all Malaysian PTLs and in 60% of the Danish PTLs. In HD and the IM cases, the mutations were present in about 30%. The 30-bp deletion and the single base mutations occurred independently, and mutations were detectable in the majority of EBV type B-positive cases. These findings suggest that the 30-bp deletion and the 7 single-base mutations in the C-terminal part of the CAO-BNLF-1 gene do not characterize a new EBV type A substrain. Rather, some of the positions of single base mutations and the 30-bp deletion are hot spots that may have mutated independently through the evolution of EBV strains.

Omeprazole 40 mg o.m. combined with amoxycillin alone or with amoxycillin and metronidazole in the eradication of Helicobacter pylori

OBJECTIVES

Our objectives were to determine the effect of dual therapy with omeprazole and amoxicillin and of triple therapy with omeprazole, amoxicillin, and metronidazole in the eradication of Helicobacter pylori (HP) and to study the long-term results of eradication in these patients.

METHODS

A prospective, randomized, controlled trial was performed. Patients who were recruited had unequivocal evidence of HP infection based on culture, histology, rapid urease test, and Gram's stain of a tissue smear. Eradication was defined as the absence of bacteria in all tests performed on both corpus and antral biopsies.

RESULTS

The infection was eradicated in 15 of 19 (78.9%) patients randomized to receive dual therapy and in 19 of 22 (86.4%) patients who received triple therapy. We followed the course of 30 patients in whom HP had been eradicated for a prolonged term (up to 12 months). All remained clear of HP. Twenty-five of 28 patients (89.3%) with duodenal ulcers in whom HP was successfully eradicated remained healed at 12 months. Fewer side effects were reported among patients who received the dual therapy.

CONCLUSIONS

Combination therapy with omeprazole and amoxicillin with or without metronidazole is effective in the eradication of HP. In particular, the dual therapy regimen with amoxicillin is not only effective but is also well tolerated by patients.

The rapid urease test in the diagnosis of Helicobacter pylori infection

With the increasing recognition of the importance of H. pylori in gastrointestinal disease, there is a need for a reliable, efficient and yet inexpensive diagnostic test. The performance of the rapid urease test (RUT) as an endoscopy suite diagnostic test was compared to the established methods of culture, histology and Gram stain of tissue smear, in 274 gastric biopsy samples. Histology had the highest sensitivity of 99.3% followed by the RUT (96.6%). Culture and Gram stain of tissue smear had 100% specificity, while the rapid urease test had 99.2% specificity. The RUT had a positive predictive value of 99.3% and a negative predictive value of 96.2%. The RUT is an inexpensive, rapid and reliable diagnostic test of H. pylori infection.

HTLV-I antibody study in normal individuals and unselected hospital patients in Malaysia

A serological investigation for human T cell leukemia virus I (HTLV-I) infection was carried out at the University Hospital, Kuala Lumpur. A total of 626 sera from a non-patient population and 1,038 sera from unselected in-patients were screened for HTLV-I antibodies using an enzyme-linked immunosorbent assay (ELISA). 27/1664 (1.6%) were found to be reactive. However, on Western blotting, only 2 sera were confirmed positive, both showing reactions for the major core (p19 and p24) and the envelope (gp46) proteins. Both of the serum samples were from unselected hospital patients. Most of the remaining sera which were reactive on screening showed indeterminate results on Western blotting. These were further tested by radioimmunoprecipitation assay (RIPA) and none of these sera gave a positive reaction. Therefore, only 2/1038 (0.19%) unselected patients could be confirmed to have antibodies to HTLV-I. None of the normal individuals screened showed a positive Western blot result. Our data indicate that HTLV-I infection is present in our population, but at a low prevalence rate.

Alpha-fetoprotein in hepatocellular carcinoma: a serological and histochemical study in Malaysian patients

Serum alpha-fetoprotein (AFP) levels and its expression in liver tissue was studied in 50 cases of histologically confirmed hepatocellular carcinoma (HCC). Serum AFP levels were elevated (greater than 20iu/ml) in 35/50 (70%) of the cases, 28 of whom had levels greater than 500 iu/ml, which is highly suggestive of HCC. These results indicate that serum AFP, by itself, is a relatively insensitive diagnostic test for HCC. Although elevated levels in high risk patients provide a specific clue, a negative result does not exclude the diagnosis of HCC. Expression of AFP by tumour cells paralleled that of serum in the majority of cases. However, tissue AFP was negative in 7 patients who had markedly elevated serum AFP. This observation may be a reflection of preferential excretion of the tumour antigen or differential expression of the antigen by the tumour cells. None of the patients with normal serum AFP demonstrated a reaction for tissue AFP. There was no correlation between AFP production and tumour differentiation.

Helicobacter pylori infection and non-ulcer dyspepsia: the effect of treatment with colloidal bismuth subcitrate

A study was undertaken to determine the role of Helicobacter pylori in non-ulcer dyspepsia (NUD) and to determine the efficacy of colloidal bismuth subcitrate (CBS) in the treatment of NUD. Seventy-one patients were randomly allocated (double blind) to CBS or placebo, two tablets twice daily for 4 weeks. The severity of dyspepsia was scored and endoscopies performed before and after treatment, and antral biopsy specimens were taken for bacteriologic and histologic examination. Forty patients had H. pylori infection, and all had changes of chronic active gastritis. H. pylori was cleared from 17 to 21 patients (81%) treated with CBS, whereas none of the 19 patients treated with placebo cleared the bacteria. Improvement in histology was noted in 15 of 21 patients (71.4%) treated with CBS, whereas no improvement was noted in any of the placebo controls. Thirty-one patients were negative for H. pylori. All had either normal gastric histology or minor degrees of inflammation. Seventeen of these patients received CBS, and 14 received placebo. All groups reported improvement in the symptom score; however, the H. pylori-positive, CBS-treated group recorded a significantly higher improvement than the other groups (p less than 0.001). Relapse of H. pylori infection after initial clearance of the bacteria was high. Twelve of 16 patients evaluated relapsed 1 month after withdrawal of CBS.

Chronic pyelonephritis: the significance of renal renin and the vascular changes in the human kidney

Hypertension complicates chronic pyelonephritis. Since arterial narrowing is common in the damaged kidney, activation of the renin-angiotensin system due to renal ischaemia has been suggested as a pathogenetic mechanism. We used an antiserum to human renin and an immunoperoxidase technique to study the anatomy of renin-containing cells (RCC) in 18 kidneys removed for pyeloneophritis. We independently assessed the degree of arterial narrowing and correlated these variables with the clinical findings. There was histological evidence of hyperplasia of RCC in 5 of the 6 hypertensive patients and in 7 of the 12 non-hypertensive cases. There was no difference in the apparent number or distribution of RCC between the hypertensive and the non-hypertensive cases. Also, the degree of arterial narrowing did not correlate with either the hyperplasia of RCC or the blood pressure of the patients. Our results do not support the hypothesis that narrowing of the intrarenal arteries is important in the pathogenesis of hypertension in pyelonephritis. In our cases, the renal veins were more severely damaged than the arteries and their lumina were often obliterated by organized thrombus. We suggest that such widespread obliteration of the renal venous tree could impair blood flow and contribute to the tissue damage in the pyelonephritic kidney.

The histopathological pattern of primary IgA nephropathy in a Malaysian patient population

In the 10-year period from October 1977 to July 1987, 149 cases of primary IgA nephropathy were histologically confirmed through renal biopsies in the Department of Pathology, University Hospital, Kuala Lumpur. The ages of these patients ranged from 5 to 72 years, with the majority in the 20-30 year age group. There was no sex preponderance. The ethnic distribution showed a significant predominance of Chinese with 107 (71.8%) Chinese, 24 (16.1%) Malays, 15 (10.1%) Indians and 3 others. A wide range of renal glomerular pathology was seen, the commonest being diffuse mesangioproliferative glomerulonephritis (59.1%). Focal proliferative glomerulonephritis (14.1%) followed by minimal change glomerulonephritis (10.7%) were next in order of frequency. Immunofluorescence studies consistently demonstrated heavy and predominant IgA deposition in the mesangium. Weak deposition of C3, IgG and IgM were also observed in various combinations.

Campylobacter pylori infection: experience in a multiracial population

Over a 15-month period, 399 patients with dyspepsia were investigated for the presence of Campylobacter pylori infection. Half of the patients (50.6%) had Campylobacter organisms in the antrum of the stomach. C. pylori was found in 96.1% of patients with histological changes of chronic active gastritis in the antrum. Of patients with duodenal and gastric ulcers, 87.8% and 87.5%, respectively, had Campylobacter organisms, as did 39.3% of patients with non-ulcer dyspepsia. C. pylori infection was most commonly found in Chinese and Indians. Although the prevalence of infection appeared to increase with age, there was an equal distribution amongst the sexes.

A unilateral mesenchymal disorder of the head

A hitherto undescribed group of lesions consisting of cystic bony lesions, exostosis, fibromatous lesion, unilateral tonsillar hypertrophy, epidermoid cyst (cholesteatoma) and hyperplasia of the mandible confined to the left side of the face is reported. The case may represent a variant of the Proteus syndrome.