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AimsThe histopathological diagnosis of low-grade dysplasia (LGD) in Barrett’s oesophagus (BO) is associated with poor interobserver agreement and guidelines dictate expert review. To facilitate nationwide expert review in the Netherlands, a web-based digital review panel has been set up, which currently consists of eight ‘core’ pathologists. The aim of this study was to evaluate if other pathologists from the Dutch BO expert centres qualify for the expert panel by assessing their performance in 80 consecutive LGD reviews submitted to the panel.MethodsPathologists independently assessed digital slides in two phases. Both phases consisted of 40 cases, with a group discussion after phase I. For all cases, a previous consensus diagnosis made by five core pathologists was available, which was used as reference. The following criteria were used: (1) percentage of ‘indefinite for dysplasia’ diagnoses, (2) percentage agreement with consensus diagnosis and (3) proportion of cases with a consensus diagnosis of dysplasia underdiagnosed as non-dysplastic. Benchmarks were based on scores of the core pathologists.ResultsAfter phase I, 1/7 pathologists met the benchmark score for all quality criteria, yet three pathologists only marginally failed the agreement with consensus diagnosis (score 68.3%, benchmark 69%). After a group discussion and phase II, 5/6 remaining aspirant panel members qualified with all scores within the benchmark range.ConclusionsThe Dutch BO review panel now consists of 14 pathologists, who—after structured assessments and group discussions—can be considered homogeneous in their review of biopsies with LGD.

Dysplasia assessment of Barrett's esophagus biopsies is associated with low observer agreement; guidelines advise expert review. We have developed a web-based review panel for dysplastic Barrett's esophagus biopsies. The purpose of this study was to test if 10 gastrointestinal pathologists working at Dutch Barrett's esophagus expert centres met pre-set benchmark scores for quality criteria. Ten gastrointestinal pathologists twice assessed 60 digitalized Barrett's esophagus cases, enriched for dysplasia; then randomised (7520 assessments). We tested predefined benchmark quality criteria: (a) percentage of ‘indefinite for dysplasia’ diagnoses, benchmark score =14% for all cases, =16% for dysplastic subset, (b) intra-observer agreement; benchmark score =0.66/=0.39, (c) percentage agreement with ‘gold standard diagnosis’; benchmark score =82%/=73%, (d) proportion of cases with high-grade dysplasia underdiagnosed as non-dysplastic Barrett's esophagus; benchmark score =1/78 (=1.28%) assessments for dysplastic subset. Gastrointestinal pathologists had seven years’ Barrett's esophagus-experience, handling seven Barrett's esophagus-cases weekly. Three met stringent benchmark scores; all cases and dysplastic subset, three met extended benchmark scores. Four pathologists lacked one quality criterion to meet benchmark scores. Predefined benchmark scores for expert assessment of Barrett's esophagus dysplasia biopsies are stringent and met by some gastrointestinal pathologists. The majority of assessors however, only showed limited deviation from benchmark scores. We expect further training with group discussions will lead to adherence of all participating gastrointestinal pathologists to quality criteria, and therefore eligible to join the review panel.

Background Dysplasia assessment of Barrett’s esophagus biopsies is associated with low observer agreement; guidelines advise expert review. We have developed a web-based review panel for dysplastic Barrett’s esophagus biopsies.Objective The purpose of this study was to test if 10 gastrointestinal pathologists working at Dutch Barrett’s esophagus expert centres met pre-set benchmark scores for quality criteria.Methods Ten gastrointestinal pathologists twice assessed 60 digitalized Barrett’s esophagus cases, enriched for dysplasia; then randomised (7520 assessments). We tested predefined benchmark quality criteria: (a) percentage of ‘indefinite for dysplasia’ diagnoses, benchmark score ≤14% for all cases, ≤16% for dysplastic subset, (b) intra-observer agreement; benchmark score ≥0.66/≥0.39, (c) percentage agreement with ‘gold standard diagnosis’; benchmark score ≥82%/≥73%, (d) proportion of cases with high-grade dysplasia underdiagnosed as non-dysplastic Barrett’s esophagus; benchmark score ≤1/78 (≤1.28%) assessments for dysplastic subset.Results Gastrointestinal pathologists had seven years’ Barrett’s esophagus-experience, handling seven Barrett’s esophagus-cases weekly. Three met stringent benchmark scores; all cases and dysplastic subset, three met extended benchmark scores. Four pathologists lacked one quality criterion to meet benchmark scores.Conclusion Predefined benchmark scores for expert assessment of Barrett’s esophagus dysplasia biopsies are stringent and met by some gastrointestinal pathologists. The majority of assessors however, only showed limited deviation from benchmark scores. We expect further training with group discussions will lead to adherence of all participating gastrointestinal pathologists to quality criteria, and therefore eligible to join the review panel.

Metastatic rectal cancer patients could benefit from novel therapeutic approaches. The signaling network formed by chemokines and their receptors can promote metastasis and resistance to current anticancer treatments. This study assessed the expression of chemokine receptor 4 (CXCR4) and its ligand CXCL12 immuhistochemically in stage IV rectal tumors. Paraffin-embedded primary tumor collected before and after local radiotherapy and systemic treatment with bevacizumab, oxaliplatin and capecitabine was analyzed. Receptor and ligand expression was assessed in the cytoplasm and nucleus of tumor, stromal and normal rectal crypt cells. Baseline expression of CXCR4 and CXCL12 was correlated with patients' pathologic response to treatment. At diagnosis (n=46), 89% of the rectal tumors expressed cytoplasmic CXCR4 and 81% CXCL12. Nuclear CXCR4 expression in tumor cells was present in 30% and nuclear CXCL12 expression in 35% of the tumors. After radiochemotherapy and administration of bevacizumab, nuclear CXCL12 expression was observed in 79% of residual tumors, as compared to 31% of the paired tumor samples expressing nuclear CXCL12 before treatment (P=0.001). There were no differences in CXCR4 or CXCL12 expression at baseline between the patients who had (n=9) and did not have (n=30) a pathologic complete response. Our results show that CXCR4 and CXCL12 are extensively expressed in primary rectal tumors of patients presenting with metastatic disease, while radiochemotherapy and bevacizumab further upregulate CXCL12 expression. These data indicate the importance of the CXCR4/CXCL12 axis in rectal tumor biology, and may suggest the CXCR4/CXCL12 receptor-ligand pair as a potential therapeutic target in metastatic rectal cancer.

Microvillus inclusion disease (MVID) is a rare congenital enteropathy associated with brush border atrophy and reduced expression of enzymes at the enterocytes’ apical surface. MVID is associated with mutations in the MYO5Bgene, which is expressed in all epithelial tissues. Whether organs other than the intestine are affected in MVID is unclear. We report 2 patients with MVID that developed renal Fanconi syndrome while receiving total parenteral nutrition. Renal Fanconi syndrome has been correlated to apical plasma membrane defects in kidney proximal tubular epithelial cells. The aim of the present study was to determine whether MYO5Bmutations in these patients correlate with similar apical plasma membrane defects in renal tubular epithelial cells as observed in the intestine.

Microvillus inclusion disease (MVID) is a rare congenital enteropathy associated with brush border atrophy and reduced expression of enzymes at the enterocytes' apical surface. MVID is associated with mutations in the MYO5Bgene, which is expressed in all epithelial tissues. Whether organs other than the intestine are affected in MVID is unclear. We report 2 patients with MVID that developed renal Fanconi syndrome while receiving total parenteral nutrition. Renal Fanconi syndrome has been correlated to apical plasma membrane defects in kidney proximal tubular epithelial cells. The aim of the present study was to determine whether MYO5Bmutations in these patients correlate with similar apical plasma membrane defects in renal tubular epithelial cells as observed in the intestine. Biopsies from kidney, duodenum, ileum, jejunum, and colon of 2 patients with MVID carrying MYO5Bmutations and of age-matched controls were fixed in paraffin and analyzed with immunohistochemistry and transmission electron microscopy. Structural defects of the brush border and apical recycling endosome organization are observed in enterocytes of all of the segments of the small intestine and colon. MYO5Bmutations in patients with MVID with renal Fanconi syndrome do not correlate with aberrant apical plasma membrane morphology or altered apical recycling endosome organization in renal tubular epithelial cells. MYO5Bmutations have divergent effects on the apical membrane system in kidney and intestinal epithelial cells. Epithelial defects presented in MVID are therefore likely triggered by intestine-specific factors, the identification of which may provide new targets and open avenues for the development of alternative therapeutic strategies to combat this devastating disease.

Microvillus inclusion disease (MVID) is a rare autosomal recessive enteropathy characterized by intractable diarrhea and malabsorption. Recently, various MYO5Bgene mutations have been identified in patients with MVID. Interestingly, several patients with MVID showed only a MYO5Bmutation in 1 allele (heterozygous) or no mutations in the MYO5Bgene, illustrating the need to further functionally characterize the cell biological effects of the MYO5Bmutations.

Microvillus inclusion disease (MVID) is a rare autosomal recessive enteropathy characterized by intractable diarrhea and malabsorption. Recently, various MYO5Bgene mutations have been identified in patients with MVID. Interestingly, several patients with MVID showed only a MYO5Bmutation in 1 allele (heterozygous) or no mutations in the MYO5Bgene, illustrating the need to further functionally characterize the cell biological effects of the MYO5Bmutations. The genomic DNA of 9 patients diagnosed as having MVID was screened for MYO5Bmutations, and quantitative polymerase chain reaction and immunohistochemistry on the material of 2 patients was performed to investigate resultant cellular consequences. We demonstrate for the first time that MYO5Bmutations can be correlated with altered myosin Vb messenger RNA expression and with an aberrant subcellular distribution of the myosin Vb protein. Moreover, we demonstrate that the typical and myosin Vb–controlled accumulation of Rab11a- and FIP5-positive recycling endosomes in the apical cytoplasm of the cells is abolished in MVID enterocytes, which is indicative of altered myosin Vb function. Moreover, we report 8 novel MYO5Bmutations in 9 patients of various ethnic backgrounds with MVID, including compound heterozygous mutations. Our functional analysis indicates that MYO5Bmutations can be correlated with an aberrant subcellular distribution of the myosin Vb protein, and apical recycling endosomes, which, together with the additional compound heterozygous mutations, significantly strengthen the link between MYO5Band MVID.

The impact of the reported number of lymph nodes at pathologic examination of colon specimens on survival was studied.

Chronic sennoside use induces melanosis coli (MC) and possibly increases colorectal cancer risk. Sennosides alter colonic crypt length, proliferative activity, and bcl-2 expression 18 h after administration. To investigate possible mechanisms for carcinogenesis, the effects of acute sennoside use and the presence of MC on colorectal epithelium were studied. Colorectal biopsies from 15 subjects receiving sennosides 6 h before sigmoidoscopy (Sen), 15 controls (NSen), and 27with MC [11 moderate (MMC) and 16 severe (SMC)]. were analysed for degree of apoptosis (H&E staining), immunohistochemical p53, p21/WAF and bcl-2 expression, and proliferative activity (labelling index, LI). Apoptosis (p=0.0004), intensity of p53 staining (p=0.01), and p21/WAF expression (p=0.008) were increased in Sen and SMC compared with NSen and MMC. p53 expression was increased in Sen (p=0.004). No difference in bcl-2 expression or LI was observed. Crypts were shorter in Sen (p=0.05) and longer in SMC (p=0.04) than in NSen. It is concluded that sennosides acutely induce apoptosis of colonic epithelial cells, presumably by a p53, p21/WAF-mediated pathway, resulting in shorter crypts. In severe melanosis coli, apoptosis seems to be delayed, causing longer crypts without a rise in proliferative activity or bcl-2 expression. This escape from a presumably protective mechanism may enhance the risk of carcinogenesis during chronic sennoside use. Copyright © 2001 John Wiley & Sons, Ltd.

Chronic sennoside use induces melanosis coli (MC) and possibly increases colorectal cancer risk. Sennosides alter colonic crypt length, proliferative activity, and bcl‐2 expression 18 h after administration. To investigate possible mechanisms for carcinogenesis, the effects of acute sennoside use and the presence of MC on colorectal epithelium were studied. Colorectal biopsies from 15 subjects receiving sennosides 6 h before sigmoidoscopy (Sen), 15 controls (NSen), and 27with MC [11 moderate (MMC) and 16 severe (SMC)]. were analysed for degree of apoptosis (H&E staining), immunohistochemical p53, p21/WAF and bcl‐2 expression, and proliferative activity (labelling index, LI). Apoptosis (p=0.0004), intensity of p53 staining (p=0.01), and p21/WAF expression (p=0.008) were increased in Sen and SMC compared with NSen and MMC. p53 expression was increased in Sen (p=0.004). No difference in bcl‐2 expression or LI was observed. Crypts were shorter in Sen (p=0.05) and longer in SMC (p=0.04) than in NSen. It is concluded that sennosides acutely induce apoptosis of colonic epithelial cells, presumably by a p53, p21/WAF‐mediated pathway, resulting in shorter crypts. In severe melanosis coli, apoptosis seems to be delayed, causing longer crypts without a rise in proliferative activity or bcl‐2 expression. This escape from a presumably protective mechanism may enhance the risk of carcinogenesis during chronic sennoside use. Copyright © 2001 John Wiley & Sons, Ltd.

Barrett's esophagus (BE) is a premalignantcondition, due to chronic gastroesophageal reflux.Effective antireflux therapy may diminish cancer risk.To evaluate this option an intermediate marker isneeded. We developed a methodology for measurement ofepithelial cell proliferative activity of Barrett'smucosa as an intermediate marker and correlated theactivity with traditional cancer risk markers and other parameters. Fifty-six patients (21-74 years ofage) with Barrett's esophagus and established acidgastroesophageal reflux were included. Biopsies weretaken from Barrett's mucosa at 3-cm intervals. Reflux was measured by 24-hr pH-metry. Proliferativeactivity was determined using in vitro labeling with5-bromodeoxyuridine and immunohistochemistry and wasexpressed as labeling index (LI). The length of BE correlated with erect acid reflux (P = 0.002).LI in specialized columnar metaplasia was higher than ingastric metaplasia, especially in crypt epithelium (P< 0.05). Multiple regression analysis revealed independent positive correlations for surfaceLI with dysplasia (P = 0.011), distance from theincisors (P = 0.041), and crypt LI (P = 0.000). Crypt LIshowed an independent positive correlation with the length of BE (P = 0.033) and type ofmetaplasia (P = 0.007). In conclusion, epithelial cellproliferative activity of BE correlates with severalknown risk factors for cancer. Proliferative activity is an attractive intermediate marker toevaluate the effects of interventional measures todecrease cancer risk in Barrett's esophagus.

Between November 1987 and January 1996 pelvic exenteration for primary rectal cancer was carried out in 11 male patients. Two underwent a primary resection with subtotal cystectomy. In the remaining nine patients, the treatment commenced with a staging laparotomy and the fashioning of an end colostomy of the descending colon, followed by preoperative radiotherapy (50–56 Gy in 5 weeks). Total exenteration with ureteroileo-cutaneostomy was carried out 4–6 weeks later. In two patients, the exenteration was performed despite the detection of hepatic metastases during the second laparotomy. The pathological staging was T4in six and T3in five patients. The immediate postoperative course was uneventful in eight patients and their hospital stay averaged 20 days. Serious postoperative complications prolonged the hospital stay of three patients. Three died during the first 6 months. Recurrent disease caused the death of three of the eight remaining patients: one locoregional (7.5 years after surgery) one from pre-existing hepatic metastases (18 months after surgery) and one from the combination of locoregional and distant recurrence (15 months after surgery). Four patients are on follow-up without evidence of disease, 96, 43, 23 and 22 months after surgery. One patient is alive 20 months after exenteration, with two pulmonary metastases having been recently excised.

Fourteen HBsAg-positive patients received a liver transplant in Groningen. Two were HBeAg-positive and 12 HBeAg-negative. No anti-HBs immunoglobulin was given at the time. Both HBeAg-positive and 9 of 12 of the HBeAg-negative patients became HBsAg-positive again after transplantation. Virus titers were tested in eight patients. Two HBeAg-negative patients were HBV-DNA-negative at transplantation and are still HBV-DNA-negative one-and-half-years after transplantation, both by the branched DNA hybridization technique and by PCR (cut-off values 0.7 × 106 and 103 HBV genomes/ml, respectively). One patient who had a low HBV-DNA titer at transplantation remained PCR-positive thereafter, but became HBsAg-negative. All other patients were HBV-DNA-positive and had a recurrence that rapidly led to high HBV titers. The liver histology was characterized by fibrosis and cirrhosis, centrilobular cholestasis and high expression of HBsAg and HBcAg, but with little inflammatory infiltrate. We conclude from these results that without anti-HBs immunoglobulin prophylaxis there is a high rate of HBV recurrence after transplantation. The current policy is that patients who test negative in the HBV-DNA dot-blot assay (< 107 genomes/ml) are transplantation candidates and are treated with high-dose anti-HBs immunoglobulin after transplantation. HBV-DNA-positive patients (>107 genomes/ml) remain poor candidates for liver transplantation, even with anti-HBs immunoprophylaxis.

Purpose: We investigated the role of Tamm-Horsfall protein in interstitial cystitis. Materials and Methods: Urinary Tamm-Horsfall protein excretion was analyzed in interstitial cystitis patients and controls, and bladder biopsy specimens were stained immunohistochemically for Tamm-Horsfall protein. Results: Urinary Tamm-Horsfall protein levels in 28 women with interstitial cystitis were statistically significantly greater than those in 25 female controls. No positive staining for Tamm-Horsfall protein was demonstrated in the bladder tissue from 10 interstitial cystitis cases. Conclusions: The results support the notion that interstitial cystitis may have a systemic etiology. In addition, this assay might have clinical value in the diagnosis of interstitial cystitis.

Pseudo-Gaucher cells are reticuloendothelial cells that are found in several diseases. We report a case of pulmonary tuberculosis in which extensive pulmonary involvement with these cells resulted in fatal respiratory failure.