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In 3 patients, 2 men aged 46 and 51 years and a woman aged 54 years, with colorectal cancer there was insufficient information on the basis of the family history to diagnose 'hereditary non-polyposis colorectal cancer' (HNPCC). Further investigation showed microsatellite instability in the tumour material, an indicator for a mutation in DNA-'mismatch repair' (MMR-) genes. Immunohistochemical study of lymphocytes showed an absence of the gene products MSH2 and MSH6. Study of the MMR genes revealed a pathogenic germ-line mutation in MSH2. All three patients were satisfied with genetic testing of the MMR-genes as this gave their children and their family members the opportunity to clarify genetic status. HNPCC is a clinical diagnosis, based on family history. As family history taking is often incomplete, the diagnosis is regularly not considered. The following individual criteria can help to recognize a patient at risk for HNPCC: (a) colorectal cancer diagnosed below 50 years of age, (b) second colorectal cancer, (c) a combination of colorectal and endometrial cancer.  相似文献   
13.
In vitro studies suggest that a deficient mismatch repair (MMR) system reduces 5-Fluorouracil cytotoxicity. Colon cancer (CC) in hereditary nonpolyposis colorectal cancer (HNPCC) is due to a dysfunctioning MMR gene that leads to microsatellite instability (MSI). Clinical studies on the efficacy of 5-Fluorouracil (5-FU) in MSI high tumours are contradictory. In a retrospective study, we compared the survival of subjects with stage III CC from HNPCC families that were treated with and without adjuvant 5-FU. The Dutch HNPCC family registry was used. Information on adjuvant chemotherapy for stage III CC was obtained from subjects of families with a mutation and/or who fulfilled the AMS criteria or who were strongly suspicious for HNPCC. CC specific survival was calculated. Observation time was measured either until the date of death, date of a second primary CC or until the closing date of the study, i.e., June 1, 2001. Statistical analysis was done by Kaplan-Meier survival analysis. A total of 92 subjects with stage III CC were included. Twenty-eight of them (17 males) had adjuvant treatment with 5-FU. The median follow-up was 4 (range: 1-17) years; 8 subjects died of CC. The 5-year survival was 70% (95% Cl: 49-90). Sixty-four subjects (36 males) did not have adjuvant therapy. Their median follow-up was 6 (range: 0-23) years. Twenty of them died of CC. The 5-year survival in this group was also 70% (95% Cl: 59-83). To date, the selection of patients with CC for 5-FU treatment is based on the stage rather than the biology of the tumour. In our study, the 5-year survival of subjects treated with and without adjuvant 5-FU did not differ. Further studies are necessary to elucidate the role of MSI in 5-FU treatment of MSI-H tumours in HNPCC.  相似文献   
14.
A 21-year-old man was admitted because of upper abdominal pain and cholestasis. Endoscopic retrograde cholangiopancreatography was suggestive of primary sclerosing cholangitis. During follow-up the patient developed symptoms which were not compatible with primary sclerosing cholangitis, i.e. icterus and weight loss. Finally the patient died, almost three years after presentation, because of a metastatic adenocarcinoma which had arisen from biliary papillomatosis. Biliary papillomatosis is characterised by papillary adenomatous proliferation of the bile duct epithelium. It has a high chance of malignant degeneration. The only curative option would have been transplantation of the liver and biliary system, but this ought to have happened at an early stage before malignant degeneration had occurred.  相似文献   
15.
BACKGROUND: Epidemiologic studies suggest that coffee use might protect against colorectal cancer. Inconsistencies as to the effect of coffee use and colorectal cancer between epidemiologic studies might be related to the type of coffee brew. OBJECTIVE: We studied the effect of unfiltered coffee consumption on putative biomarkers for colonic cancer risk. DESIGN: A total of 64 healthy volunteers (31 men and 33 women), with a mean age of 43 +/- 11 years were randomly assigned to two groups in a crossover design, with two intervention periods of 2 weeks separated by a washout period of 8 weeks. Treatments were 1 L of cafetière (French press) coffee daily or no coffee. At the end of each intervention period, fasting blood samples, colorectal biopsies and 48 h faeces were collected. RESULTS: No effect of coffee on colorectal cell proliferation, assayed by estimating the Proliferating Cell Nuclear Antigen labelling index, was seen. Additionally, no effects were seen on the concentrations of faecal soluble bile acids and colorectal mucosal glutathione S-transferase activity. However, unfiltered coffee significantly increased the glutathione content in the colorectal mucosa by 8% and in plasma by 15%. Other aminothiols in plasma also increased on coffee. CONCLUSION: Unfiltered coffee does not influence the colorectal mucosal proliferation rate, but might increase the detoxification capacity and anti-mutagenic properties in the colorectal mucosa through an increase in glutathione concentration. Whether this effect indeed contributes to a lower colon cancer risk remains to be established.  相似文献   
16.
Meat consumption and meat preparation methods are thought to be associated with the risk of sporadic colorectal cancer, and possibly adenomas. As the same somatic mutations occur in sporadic adenomas and hereditary non-polyposis colorectal cancer (HNPCC)-related adenomas, similar exogenous factors may play a role in the development of both types of adenoma. In a case control study among 57 sporadic colorectal adenoma cases and 62 adenoma cases from HNPCC families (and 148 adenoma-free controls) from the Netherlands, we examined whether meat consumption and preparation are similarly associated with sporadic and suspected HNPCC colorectal adenomas. Frequency of meat consumption was not significantly associated with adenoma risk in our population of sporadic and HNPCC family cases and controls (Odds Ratios (OR) for high versus low consumption were 1.0 and 0.6, respectively). Interestingly, consumption of red meat and specific preparation methods (i.e., "not adding any water" and " closed lid with most meat types") slightly, but non-significantly, increased the risk of adenomas in the sporadic group only (OR, 95% Confidence Interval (CI): 4.1, 0.7-23.0, 2.0, 0.6-6.5 and 2.6, 0.9-7.2, respectively). This is the first study to examine possible differences or similarities in risk factors for sporadic and HNPCC colorectal carcinogenesis. Our results do not provide support for meat consumption as a risk factor for adenoma formation in HNPCC family members. Some characteristics of habitual meat preparation in the Netherlands may, however, increase the risk of sporadic adenomas.  相似文献   
17.
The hereditary colonic cancer syndrome without polyposis, hereditary non-polyposis colorectal cancer (HNPCC), is usually divided into 2 main categories: hereditary site-specific colorectal cancer (Lynch syndrome I) and colorectal cancer in association with other forms of cancer (Lynch syndrome II). One problem associated with Lynch II is the uncertainty as to which types of cancer form part of the hereditary tumour spectrum. The present study was performed to obtain more information about the tumour spectrum of HNPCC. In the 24 HNPCC families studied, 104 patients had colorectal cancer (mean age at diagnosis: 46 years) and in 4 of the families this was the only type of cancer to occur. Sixty-five extra-colonic tumours were diagnosed in 20 families. Endometrial carcinoma was found in 16 patients belonging to 12 families. Cancer of the stomach occurred in 10 patients representing 5 families, and mainly in the older generations. Urinary-tract tumours were found in 8 patients from 4 families. Second primary tumours were diagnosed in 13 of the 16 patients with endometrial cancer, in 4 of the 10 patients with stomach cancer and in 7 of the 8 patients with a urinary-tract tumour. Many other types of carcinoma were found as well, but less frequently. In our families, the trait appears to be transmitted by patients with cancer of the stomach, endometrium or urinary tract, because some of their children have developed colorectal cancer. The findings suggest that, in these 24 HNPCC families, carcinomas of the endometrium, stomach and urinary tract belong to the hereditary tumour spectrum. Definite assignment of tumours to this spectrum will become possible only after a sensitive and specific biomarker becomes available. The screening programme should depend on which and how many extra-colonic tumours occur in a family.  相似文献   
18.
BACKGROUND: Peptide YY (PYY) is a gut hormone produced by endocrine cells in the distal small bowel, colon, and rectum. PYY inhibits upper gastrointestinal secretory and motor functions. The aim of this study was to determine whether basal and postprandial plasma PYY levels in patients with proctocolectomy and ileal pouch-anal anastomosis (IPAA) are reduced and to determine the relationship between plasma PYY and plasma cholecystokinin (CCK) levels. METHODS: Plasma concentrations of PYY and CCK were measured before and after ingestion of a standardized breakfast in 14 IPAA patients and in 12 healthy control subjects. RESULTS: Basal PYY was slightly lower in the IPAA patients than in the controls (8.3 +/- 0.3 versus 9.3 +/- 1.1 pM; not significant). Ingestion of the meal induced a small but significant increase of PYY to a maximum of 10.9 +/- 0.9 pM in patients. Integrated postprandial PYY was markedly reduced in patients when compared with the controls (1725 +/- 66 pM*180min versus 3194 +/- 480 pM*180 min; P < 0.005). Plasma PYY concentrations were inversely correlated with plasma CCK concentrations in the 2nd and 3rd h after the meal (r = -0.86; P = 0.0001). CONCLUSION: PYY release in response to meal ingestion is markedly reduced but not completely absent in patients with proctocolectomy and ileal pouch-anal anastomosis. The inverse relationship between circulating PYY and CCK in the late postprandial phase is compatible with a negative feedback regulation of CCK release by endogenous PYY.  相似文献   
19.
Benign esophageal cysts are very rare embryonic malformations. In adults, esophageal cysts are mostly asymptomatic. Complications can occur due to mass effects. The diagnosis can be made using endoscopic ultrasonography (EUS), which is regarded as the diagnostic test of choice. It is a matter of debate whether relatively asymptomatic esophageal duplication cysts should be removed or whether conservative management is feasible. We report here on the case of a 37-year-old woman who presented with mild upper abdominal complaints and who was found to have compression of the distal lumen on barium esophagography. It was possible to diagnose an esophageal duplication cyst with EUS. In view of the absence of symptoms, it was decided to provide conservative management. During a 13-year follow-up period, no growth of the cyst was documented, nor did symptoms develop during this period. Close EUS observation may eliminate the need for surgery in asymptomatic patients.  相似文献   
20.
Resistance to chemotherapy is a significant problem in the treatment of colorectal carcinomas. To obtain insight into the mechanism of drug resistance, the expression of P-170 glycoprotein and biotransformation enzymes that are potentially able to contribute to drug resistance were investigated in paired samples of normal mucosa and tumors from 24 patients with colorectal cancer. In the tumors, glutathione S-transferase (GST) enzyme activity and content of GST-pi and P-170 glycoprotein were increased significantly compared with normal mucosa (P less than 0.03, P less than 0.003, and P less than 0.02, respectively). In contrast, GST-alpha and -mu, present in minor amounts compared with GST-pi, were downregulated in the tumor. Cytochrome P-450(4,5,6) and UDP-glucuronyltransferase (towards 4-nitrophenol and bilirubin) levels were significantly lower in the tumors (P less than 0.0001 and P less than 0.0002, respectively). Because decreased expression of cytochrome P-450 and increased levels of GST-pi and the P-170 glycoprotein have been implicated in (multi)drug resistance, these findings strongly suggest that in colorectal tumors the inherent resistance is multifactorial. Research to overcome this resistance should therefore be directed toward a combined treatment that eliminates all of these different mechanisms.  相似文献   
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