Cyclin/proliferation cell nuclear antigen immunohistochemistry does not improve the prognostic power of Dukes' or Jass' classifications for colorectal cancer.

Immunohistochemistry of cyclin/proliferation cell nuclear antigen (PCNA) is an attractive alternative to tumour cell proliferation activity determined by flow cytometry which has been shown to be independently predictive of survival in patients with colorectal carcinoma and to enhance Dukes' classification. Dukes' and Jass' histopathological classifications were determined in 91 patients who had undergone curative resection for cancer of the colon (n = 51) or rectum (n = 40) and followed up for a minimum of 10 years. PCNA immunohistochemistry was possible in 79 tumours. Univariate analysis revealed that Jass' (P < 0.0001) and Dukes' classifications (P < 0.0002) were powerful predictors of survival but that the PCNA index had little prognostic power (P = 0.4). Multivariate analysis of both classifications showed similar predictive power and the PCNA index improved the prediction of survival when used with either classification for patients with colon cancer (chi 2 = 5.3, 1 d.f., P = 0.02 for each combination). The PCNA index, however, was not predictive for rectal cancer. Patients with the lowest PCNA index had the worst prognosis.

Expression of proliferating cell nuclear antigen (PCNA) in gastric carcinoma: no evidence for prognostic value.

It has been proposed that immunostaining with PC10, a monoclonal antibody against proliferating cell nuclear antigen (PCNA), is of prognostic value in gastric carcinoma. Gastric carcinomas from a series of 90 patients in whom survival data were known have been studied. There was no relation between the degree of PC10 immunostaining assessed semiquantitatively and survival.

Epstein-Barr virus and carcinomas: rare association of the virus with gastric adenocarcinomas.

We have analysed 174 gastric carcinomas from the United Kingdom and from Japan for the presence of Epstein-Barr virus (EBV) using in situ hybridisation for the small EBV-encoded nuclear RNAs (EBERs). EBV was detected in the tumour cells in all of six undifferentiated gastric carcinomas with prominent lymphoid stroma (undifferentiated carcinomas of nasopharyngeal type, UCNT) but only in three of the remaining 168 typical gastric adenocarcinomas (1.8%). No differences were observed between the British and the Japanese cases. One case with an EBV-positive UCNT showed adjacent areas of EBV-negative typical adenocarcinoma. It is uncertain whether these patterns represent two independent carcinomas or whether they are the result of heterogeneous EBV infection in a single tumour. In the remaining EBV-positive carcinomas, viral transcripts were detected in virtually all tumour cells, indicating that EBV infection must have taken place early in the neoplastic process and suggesting that the virus is likely to be of pathogenetic significance for the virus-associated tumours. Immunohistology demonstrated absence of detectable levels of the EBV-encoded latent membrane protein, LMP1, and nuclear antigen, EBNA2. The BZLF1 protein which induces the switch from latent to lytic infection was demonstrated in a small proportion of the tumour cells in three cases. The close association of EBV with undifferentiated gastric carcinomas compared to the variable association with gastric adenocarcinomas suggests fundamentally different roles for the virus in the aetiology of these two malignancies.

Different clinicopathological types of segmental sclerosing glomerular lesions in adults.

Renal biopsies and kidneys from 111 adult patients with segmental sclerosing glomerular lesions were put into different morphological groups by pathologists unaware of clinical findings. 'Overload changes' (n = 11) were large glomeruli with hilar lesions. Ten of these patients had reduced renal mass. In the 'glomerular tip lesion' (n = 10) there were changes at the tubular origin in otherwise normal glomeruli. All patients in this group had the nephrotic syndrome, completely responsive to steroids. 'Mesangial hypercellularity with diffuse segmental changes at the glomerular tip', corresponding to 'early classical focal segmental glomerulosclerosis' (n = 18), differed from the glomerular tip lesion in that glomeruli were larger and hypercellular. Most patients with this classification had the nephrotic syndrome, several were given additional immunosuppression, and less than half had complete remission. 'Diffuse multiple segmental lesions', corresponding to 'late classical focal segmental glomerulosclerosis' (n = 16), presented usually with the nephrotic syndrome, and most of these patients had no response to immunosuppression. Unlike most other groups, in 'focal segmental sclerosing lesions' (n = 56) there were genuinely focal lesions, not in every glomerulus. Most patients had asymptomatic proteinuria. Pathological study is able to classify segmental lesions that would often be grouped as 'focal segmental glomerulosclerosis' into types with different pathogenesis, clinical findings, appropriate treatment, response to treatment, and prognosis.

Renal biopsy findings in hypertensive patients with proteinuria.

27 patients with hypertension and persistent proteinuria were investigated by renal biopsy. The 13 patients without structural glomerular abnormalities were younger and had less proteinuria than the other 14, but otherwise the two groups had similar clinical features. 6 of the 14 had diffuse glomerular abnormalities; the other 8 had segmental sclerosing lesions, which were mainly in the hilum of the glomeruli, as seen in states of glomerular overload. Glomeruli in all groups were larger than those in normotensive people. It is possible that hypertension causes glomerular enlargement, proteinuria, and segmental glomerular lesions because of loss of functioning glomeruli due to ischaemia.

Evidence for unique distribution of Kimmelstiel-Wilson nodules in glomeruli.

Different distributions of segmental lesions within glomeruli correspond to different pathogenetic mechanisms. A graphic method of analysis of the position of segmental lesions was applied to 106 Kimmelstiel-Wilson nodules in 10 renal biopsies from patients with diabetic glomerulonephropathy, 4 with IDDM and 6 with NIDDM. The nodules were randomly distributed in a horseshoe-shaped area corresponding to the peripheral or intralobular mesangium. This distribution was different from that of segmental lesions studied previously in the glomerular tip lesion, in vasculitic-type glomerulonephritis, and in hyperfiltration associated with reduced renal mass. Our finding is consistent with ideas that Kimmelstiel-Wilson nodules have a distinct pathogenesis not related to hyperfiltration or any other process previously investigated as a cause of characteristic distribution of segmental lesions.

Induction of cholangiocarcinoma in the Golden Syrian hamster using methylazoxymethyl acetate.

The Golden Syrian hamster, which has a bile acid profile similar to that of humans, is often used as an experimental model for cholangiocarcinoma. Unfortunately, most chemical carcinogens result in other tumour types also being induced which can be disadvantageous. In the present study, we describe the development of cholangiocarcinoma associated with precursor lesions of bile duct proliferation and dysplasia which occurred following a single i.v. dose of methylazoxymethyl acetate (10, 20 or 40 mg/kg body weight). Moreover, no other tumours were induced. This model may, therefore, prove useful in investigating the steps involved in the carcinogenesis of cholangiocarcinoma.

Comparability of hamster with human faecal unconjugated bile acids in a model of colorectal cancer.

The relationship between experimental colorectal carcinogenesis and bile acids has usually been investigated in the rat, a species with a markedly different bile acid profile from man. In this study, we show that the hamster faecal bile acid profile is similar to that in man. Rectal cancer was induced in hamsters using twice weekly instillations of N-methyl-N-nitro-N-nitrosoguanidine (MNNG) for 4 weeks at doses of 1-8 mg kg-1. The medcian (range) faecal bile acid concentrations of tumour-bearing hamsters (0.52, 0.46-0.84 mumoles g-1 faeces) was reduced compared to controls (1.08, 0.95-1.65, mumoles g-1) and non-tumour bearing MNNG treated hamsters (1.18, 0.64-1.42 mumoles g-1), largely due to a decrease in cholic acid derivatives (all p less than 0.05) at least). This model may be more suitable for studying the relationship between colorectal cancer and bile acids.

Comparison of size of juxtamedullary and outer cortical glomeruli in normal adult kidney.

Abnormally large glomeruli are susceptible to hyperfiltration-associated sclerosis. We used an established morphometric method to test the general belief that juxtamedullary glomeruli are larger than those in the outer cortex, in a population with no clinical or pathological evidence of renal disease. Overall, juxtamedullary glomeruli were significantly larger, but this varied according to the amount of global glomerulosclerosis present. Global sclerosis increased with age, particularly in the outer cortex, and the ratio of juxtamedullary to outer cortical glomerular size showed a positive correlation with overall, and outer cortical, global sclerosis. Thus in the truly normal adult kidney, juxtamedullary glomeruli are not significantly larger than outer cortical glomeruli. However, global sclerosis increases with age and is most marked in the outer cortex, and this leads to compensatory enlargement of predominantly the juxtamedullary glomeruli. These findings suggest that in single kidneys, or in conditions characterised by ischaemic glomerulosclerosis such as hypertension, morphological changes related to hyperfiltration may appear first, and therefore become most severe, in juxtamedullary glomeruli.

Use of the OM-11-906 monoclonal antibody for determining p62 c-myc expression by flow cytometry in relation to prognosis in colorectal cancer.

The expression of the c-myc protein product (p62 c-myc) and deoxyribonucleic acid (DNA) ploidy status was determined by a flow cytometric technique in 83 patients with colorectal cancer followed up for a median of 30 months (range 6-60 months). The OM-11-906 antibody, used to detect p62 c-myc, revealed a 62 kDa and 45 kDa band on Western blots in tumours. Correlation of quantitative dot blotting of tumour mRNA to flow cytometric p62 c-myc expression was good (r = 0.87, P less than 0.01). Levels of p62 c-myc varied in colorectal cancer and low levels (less than 20 fluorescein units) correlated with improved survival (log rank chi 2 = 4.69, df = 1, P = 0.03), and this was a better prognostic index than DNA ploidy (log rank analysis chi 2 = 2.38, df = 1, P less than 0.1). Although expression of the c-myc gene was found, using the OM-11-906 antibody, to be a prognostic feature in colorectal cancer, these and other results need to be interpreted with caution given the presence of two protein bands by Western blotting.

Determinants of glomerular cross-sectional area.

A method of measurement of glomerular cross-sectional area was applied to 267 renal biopsies from 19 groups of patients with well-defined pathological and clinical conditions. There was a correlation between the mean glomerular area for each group and the percentage of global sclerosis in each group. A few groups had glomeruli that were larger than would be expected from their percentage of global sclerosis, probably due to cellular proliferation and/or infiltration. A few groups had glomeruli that were smaller than would be expected from their percentage of global sclerosis, probably due to ischaemic shrinkage. These observations indicate that as well as the known influence of body size on the glomerular area, the number of functioning glomeruli in the body has an important effect on the glomerular area.

Analysis of the position of segmental lesions in glomeruli in vasculitic-type glomerulonephritis and other disorders.

A method was developed of plotting the position of segmental lesions in glomeruli on histological sections of kidney. Using a Leitz Imagan semi-automatic image analyser, the outline of lesions was traced, as was the outline of Bowman's capsule. The centre of gravity of a lesion, computed by the image analyser, was plotted with reference to the line through the hilum and the centre of gravity of the glomerulus, by taking its angle to that line and its proportional distance between that line and Bowman's capsule. Points representing all lesions were transferred onto a circle graphically representing a glomerulus. Lesions in 11 renal biopsies with the glomerular tip lesion were clustered at the tubular origin. Lesions in four necropsy kidneys from patients with one kidney were clustered at both the vascular pole and the tubular origin. Lesions in 13 renal biopsies with acute vasculitic-type glomerulonephritis were shown to be randomly scattered by nearest-neighbour analysis, after allowance had been made for an edge effect due to the method of plotting lesions and for an area where the arterioles passed through Bowman's capsule. Scientific analysis of the position of segmental lesions is possible and has confirmed previous suggestions that there are at least three general sites in which these lesions can be distributed in glomeruli: at the tip, at the vascular pole, and randomly.

Comparison of deoxyribonucleic acid ploidy and nuclear expressed p62 c-myc oncogene in the prognosis of colorectal cancer.

A simultaneous flow cytometric assay of the nuclear expressed protein product of the c-myc oncogene p62 and deoxyribonucleic acid (DNA) ploidy in archival paraffin-embedded tumor material was undertaken in 179 patients with colorectal cancer, followed for up to 9 years. DNA ploidy showed a survival advantage for diploid tumors (chi 2(1) = 5.39, p = 0.020) and could be used to further divide patients with Dukes' A tumors (chi 2(1) = 4.87, p = 0.027) and Dukes' C tumors (chi 2(1) = 5.33, p = 0.021). By dividing patients into 2 levels of tumor expression of p62 c-myc, there was a trend for improved survival in patients with low expression (chi 2(1) = 3.65, p = 0.056). A combination of ploidy status and p62 c-myc expression improved upon survival prediction by ploidy alone in providing 3 groups (chi 2(2) = 7.86, p = 0.0197). While these results do not suggest a replacement for the Dukes' staging for prognosis (chi 2(3) = 33.82, p less than 0.00001), they strongly support the concept that enhanced expression of c-myc oncogene is associated with the progression of colorectal cancer.

Assessment of glomerular size in renal biopsies including minimal change nephropathy and single kidneys.

A method of assessing glomerular size on sections of post-mortem kidney was adapted for use on needle biopsies of kidney. A semi-automatic image analyser was used to measure the cross-sectional area of the outline of Bowman's capsule on all glomeruli in renal biopsies. The mean of approximately the largest 25 per cent of areas was calculated. The method was used to compare glomeruli in 13 control patients without obvious structural abnormalities with those in 10 patients with a single kidney, 22 with minimal change nephropathy, and 20 with membranous nephropathy. Patients were at least 14 years old. Glomeruli in minimal change nephropathy were significantly smaller than those in all other groups. Glomeruli in single kidneys were significantly larger than those in all other groups. Glomeruli in membranous nephropathy were the same size as controls. Any differences between groups could not be explained by differences in body build. It is possible that in adults glomeruli in minimal change nephropathy are abnormally small. The method of assessing glomerular size can be used on renal biopsies as well as on sections of whole kidney.

Mucosal mast cells in reflux gastritis and chronic (type B) gastritis.

The histological features that characterize alkaline reflux gastritis are typical of the histamine-mediated response to tissue injury. We have investigated this in nine patients with symptomatic reflux gastritis following partial gastrectomy for duodenal ulcer by determining the gastric mucosal mast cell count before and after Roux-en-Y biliary diversion. Following diversion, the histological picture changed from that of reflux gastritis to type B chronic gastritis in all cases. The mean mucosal mast cell count in all patients was 47.57/mm2 before diversion and 123.33/mm2 after diversion (P less than 0.05). Analysis of the paired data, in which eight out of nine patients showed a rise in mucosal mast cell numbers following bile diversion, also showed a significant difference before and after surgery (P less than 0.01). The gastric mucosal mast cell count is significantly less in reflux gastritis than in type B chronic gastritis. This is most likely to be due to increased degranulation, which would explain why striking vascular changes occur in the absence of inflammatory cell infiltration in reflux gastritis.

Effect of Roux-en-Y biliary diversion on Campylobacter pylori.

To assess the effect of biliary diversion on gastric colonization by Campylobacter pylori, we undertook a retrospective histologic study of 24 patients with symptomatic bile reflux after peptic ulcer surgery, who had endoscopic gastric biopsies performed before and after a Roux-en-Y operation. The time interval between the preoperative and postoperative endoscopic examinations ranged from 0.8 to 9.8 yr (mean 4.7 yr). The partial gastrectomy specimen, which had been resected at the initial operation, was available for assessment in 12 patients (50%). Biopsy specimens were assessed for the presence of C. pylori and scored for severity of reflux gastritis by the use of a histologic grading system. Ten of the 12 partial gastrectomy specimens (83%) were C. pylori-positive. Only 13 of the 24 patients (54%) were C. pylori-positive before the Roux-en-Y operation, rising to 22 (92%) after biliary diversion (p = 0.008). The median reflux score was 6 in the partial gastrectomy specimens; it rose to 11 before the Roux-en-Y operation and fell again to 6 after biliary diversion (p less than 0.001). These results suggest that C. pylori may recolonize the gastric remnant after biliary diversion.