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BACKGROUND: The DNA content of oesophageal tumour cells is a prognostic factor in untreated patients. To investigate whether DNA ploidy is useful to select patients for neoadjuvant therapy it is of interest to develop a method allowing reliable flow cytometric analysis of the DNA content of tumour cells obtained by forceps biopsy during endoscopy before start of therapy. METHODS: Freshly frozen forceps biopsy samples from 30 patients with oesophageal cancer were disaggregated. DNA was stained with propidium iodide and ploidy was determined by flow cytometry. To enhance sensitivity epithelial cells were simultaneously labelled with anti-cytokeratin antibodies. Results were compared with image analysis. To evaluate the sampling error, parallel measurements were done in 10 patients by image analysis on forceps biopsies obtained during endoscopy before surgery and on the resected tumour. RESULTS: The sensitivity to detect aneuploidy was lower for standard flow cytometry than for image analysis (13 versus 33%). The overall sensitivities were identical using a double labelling technique with additional cytokeratin-staining of the epithelial cells, but divergent results were obtained in 2 cases, where detection of aneuploidy was either possible with image analysis or with double labelling flow cytometry only. DNA content of samples gained by forceps biopsies and surgically resected tumours was concordant in 8 of 10 cases. In 2 patients, aneuploidy was detected only in the surgically resected tumour but not in the pre-operatively obtained forceps biopsies. CONCLUSIONS: A flow cytometric method for routine determination of the DNA ploidy of cells obtained by forceps biopsies from patients with oesophageal cancer was developed and evaluated against image analysis. The technique allows the prediction of DNA content before tumour resection, and might be used for optimising therapy and the patient's quality of live.

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BACKGROUND AND STUDY AIMS: Standardization of the endoscopic report is a key issue for future research in the field of digestive endoscopy. The Minimal Standard Terminology (MST) has been proposed by the European Society for Gastrointestinal Endoscopy (ESGE) as a structured language for production of computerized endoscopic reports. The aim of this study was to validate version 1.0 of this terminology prospectively, by collecting cases in a multicenter, multilingual trial. METHODS: Endoscopic cases (esophagogastroduodenoscopy [EGD], colonoscopy, endoscopic retrograde cholangiopancreatography [ERCP]) were prospectively collected in nine university hospitals in Europe, using the same software. Reports were produced in the local language, but the software allowed comparison of reports between languages, and global analysis of the database. Outcome measures were the adequacy of terms proposed in the MST to describe "reasons for performing an endoscopy", "findings", and "endoscopic diagnoses", frequency of use and content of free-text fields, and types of lesions described. RESULTS: A total of 6,232 reports were analyzed, including 3,447 gastroscopies, 1,743 colonoscopies, and 1,042 ERCPs. Overall, terms originally contained in the MST were adequate to describe fully 91.0% of all examinations where "reasons for endoscopy" were described, 99.5 % of examinations where "findings" were described, 95.8% of all examinations containing descriptions of "endoscopic diagnosis", 98.9% of examinations containing descriptions of "additional diagnostic procedures", and 94.8 % of examinations containing descriptions of "additional therapeutic procedures". Free-text fields were only used in the other cases (less than 5% of cases in average). CONCLUSIONS: The MST appeared adequate to cover a large part of routine endoscopy reports, and could thus be used as a tool for standardization of endoscopic reports in clinical practice. The latter could be significantly improved by the use of a structured and standardized terminology for the production of endoscopic reports.

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The wider use of computers for the management of endoscopic data and the use of electronic endoscopes for the production of high quality endoscopic images has made the standardization of terminology and images formats necessary in digestive endoscopy reports. The European Society for Gastrointestinal Endoscopy and the American Society for Gastrointestinal Endoscopy have combined their efforts to propose a Minimal Standard Terminology for Computerized Databases in Endoscopy. This terminology is based on the following principles: no term describing findings less frequent than 1%, of the daily practice, and no term based on subjective impressions. The Minimal Standard Terminology has been developed according to the natural process of constructing an endoscopic report in natural language and deals with the following: reasons for performing the examination, endoscopic findings, endoscopic diagnosis, additional therapeutic and diagnosis procedures (biopsies, etc.). It is subdivided according to the main organs examined with an endoscopy. Until now, the Minimal Standard Terminology was tested in many centers and was shown to accurately cover 95% of routine examinations for the upper gastrointestinal tract, colonoscopy and cholangio-pancreatography. It is currently being tested in an a prospective way in several centers in Europe (with a grant from the European Commission DGXIII-C4) and in the USA (with grant from the AHDHF).

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OBJECTIVE: A previous phase I trial in 14 pretreated patients with progressive advanced colorectal cancer demonstrated 750 mg/m2 to be the maximum tolerable dose of 5-fluorouracil (5-FU) administered as a five-day continuous infusion modulated by short infusions of 100 mg/m2 folinic acid twice daily. The dose-limiting toxicities were hand-foot syndrome and severe mucositis. A response rate of 21% and 50% stable disease could be achieved. In order to determine the effectiveness and tolerability, we initiated a multicenter phase II trial applying a 650 mg/m2 recommended dose of 5-FU and 100 mg/m2 folinic acid twice daily every three weeks. PATIENTS AND METHODS: From January 1994 to July 1996, 88 advanced and progressive colorectal cancer patients either previously treated with a bolus schedule of 5-FU and folinic acid (34 patients) or without (54 patients) previous chemotherapy were included in this trial. RESULTS: In the group of previously treated patients, therapy led to 6% (2 of 34 patients) remissions while stable disease could be observed in 68% (23 of 34 patients) of the patients. The median survival time was 14 months. The main toxicity was mucositis grade 3 in 15% of the previously treated patients and 10% in the nonpretreated patients. In the population of nonpretreated patients, the overall response rate was 15% (eight of 54 patients) and stable disease could be induced in 67% (36 of 54 patients). The median survival time was 13.7 months. CONCLUSION: This regimen is an active second-line therapy in advanced colorectal cancer with minimal toxicity, thus preserving the quality of life during palliative chemotherapy. Antitumor activity in previously untreated patients does not seem superior to that obtained with weekly regimens applying 24- or 48-hour continuous infusions of 5-FU and folinic acid.

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In chronic cholestatic liver disease hydrophobic and potentially cytotoxic bile acids are assumed to accumulate in the liver. To test this hypothesis we investigated bile acid levels and pattern in livers and serum of patients with, (A) end-stage chronic cholestatic liver disease, and with (B) end-stage cirrhosis of alcoholic/chronic hepatitic origin who underwent liver transplantation. Bile acids were also analyzed in (C) normal liver tissue. Levels of bile acids were 215 +/- 39.1 nmol/g liver (wet weight) in chronic cholestasis and 120 +/- 32.7 and 56.1 +/- 24.2 nmol/g liver in group B and group C (P < 0.01 and P < 0.005), respectively. Cholic acid was the prevailing bile acid in chronic cholestasis (51%) and was elevated eight-fold as compared to group C (P < 0.005). Chenodeoxycholic acid contributed 41% to total bile acids and was elevated four-fold (P < 0.005). Deoxycholic acid contributed only 1.5% to bile acids in chronic cholestasis as compared to 27% in group C (P < 0.01) and was absent in group B. Levels of lithocholic acid tended to be increased in chronic cholestasis as compared to group C and its sulfation was impaired (P < 0.05). The pattern of serum bile acids in chronic cholestasis agreed well with the bile acid pattern in the explanted livers. We conclude that hepatic accumulation of hydrophobic chenodeoxycholic acid and impaired sulfation of lithocholic acid might contribute to tissue degeneration in chronic cholestatic liver disease due to the detergent effects of these bile acids.

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The assessment of blood flow in the gastrointestinal mucosa could be a useful indicator for the diagnosis and treatment of several diseases, such as ulcers, gastritis, colitis or early cancer. The quantity of blood flow is roughly estimated by computing the spatial hemoglobin distribution in the mucosa. The method presented here enables a practical realization by calculating approximately the hemoglobin concentration based on a spectrophotometric analysis of endoscopic true-color images, which are recorded during routine examinations. A system model based on the reflectance spectroscopic law of Kubelka-Munk is derived, which enables an estimation of the hemoglobin concentration by means of the color values of the images. Additionally, a transformation of the color values is developed, in order to improve the luminance independence. Applying this transformation and estimating the hemoglobin concentration for each pixel of interest, the hemoglobin distribution can be computed. The results obtained are mostly independent of luminance. An initial validation of the method is made by a quantitative estimation of the reproducibility.

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In acute and chronic viral disease the specific response of CD4+ T lymphocytes to certain viral proteins is an essential part of antiviral effector mechanisms. In hepatitis C virus infection, the contribution of the immune system and particularly of CD4+ T lymphocytes to the pathogenesis of disease is unknown. We serially determined the peripheral blood CD4+ T lymphocyte response to several recombinant hepatitis C virus proteins (core, NS3, NS4, NS5) and 17 overlapping synthetic peptides derived from the core sequence over up to 48 months in 43 patients with chronic hepatitis C; of these, 16 had been treated with interferon alfa (IFN). Twelve of 27 untreated patients, 4 of 4 sustained responders to IFN, 7 of 8 patients with a transient response, and 1 of 4 nonresponders showed a proliferative response to hepatitis C virus proteins. The hepatitis C virus core protein was the most immunogenic protein, and fine analysis with peptides indicated amino acids 23 to 42, 66 to 85, and 131 to 150 as immunodominant regions. In a subgroup of nine patients, proliferation assays were performed before or during IFN. In this subgroup, sustained responders but not those with a transient or no response to IFN showed a specific CD4+ immune reaction to hepatitis C viral antigens (P < .05). Infection with hepatitis C virus genotype 3a was significantly associated with a sustained response to IFN (P < .05). In general, a CD4+ T lymphocyte response was more common in patients with chronic hepatitis C who responded to interferon-alpha as compared with nonresponders.(ABSTRACT TRUNCATED AT 250 WORDS)

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A method is presented that estimates the local blood flow in the mucosa of the organs of the upper gastrointestinal tract; the method is based on the analysis of endoscopic true-color images. The quantity of blood flow is approximated by the estimation of the hemoglobin concentration in the mucosa. The first step of our algorithm consists of a neural segmentation, which excludes artifacts of the images that interfere with further computation. Next, a transformation of the image data is performed within the RGB-color space in order to obtain an estimation of the blood distribution, which is independent of the local brightness in the images. Finally the quantity of blood flow is estimated on the basis of physical laws of reflectance spectroscopy. Our method is characterized by the following features: 1) It computes an estimation of the blood flow for a whole endoscopic image; as such it is more powerful than local measuring methods; 2) Our method does not need any modifications of the endoscopic equipment; and 3) The use of our method does not put any additional strain on the patient.

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Three-dimensional reconstruction of ultrasonographic images was used to visualize hepatobiliary and pancreatic lesions and stones, and to measure gallbladder emptying. The initial experience shows that these reconstructions may be of some help in the identification of the extension of tumors and the invasion into surrounding tissues. Stones and stone fragments in the pancreas and in the gallbladder as well as the wall of the gallbladder were visualized well. If further studies will reveal a benefit for the patient, three-dimensional ultrasonography may be added to the noninvasive methods used in the diagnosis of several hepatobiliary and pancreatic diseases.

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The transjugular liver biopsy is a method which allows assessment of hepatic tissue from patients with contraindications against classical percutaneous biopsy. A catheter with a long biopsy needle within is inserted into the jugular vein and then pushed forward through the Vena cava into a hepatic vein in order to carry out the biopsy of the liver. Indications for this examination are biopsies in patients with considerably impaired coagulation or tense ascites. It is possible, if necessary, to measure free and wedged pressure within the liver veins during this examination. On average, in 93% of all examinations enough tissue is yielded to allow for satisfactory judgement of histological changes; the rate of success is little less than that with percutaneous biopsies. However, considering all aspects, this technique gives good results. Lethal complications are rare (0.17%); the total complication rate is about 12%, 0.5-2.7% are severe. Although this method needs more time and technical equipment than percutaneous biopsy, the procedure has to be considered as an important technique for the evaluation of terminal liver disease.

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Esophageal varices are of ominous significance in patients with cirrhosis. Diagnostic procedures are undertaken for evaluation of the bleeding risk. Whereas after a recent bleeding event the risk of rebleeding is high (up to 70%) and rebleeding prophylaxis is obligatory, the risk of first bleeding in patients who never bled depends on the presence of bleeding risk indicators. Endoscopy is the most powerful tool for assessment of the bleeding risk. Variceal size, the presence of the red color sign and the presence of concomitant fundic varices indicate a high risk of first bleeding. Currently used endoscopic or medical prophylaxis has a high rate of failure. On the other hand, operative measures prevent bleeding in most patients. However, the perioperative morbidity and mortality is high. Controlled studies will show whether the patients will benefit from new experimental treatment approaches (endoscopic obliteration of varices, endoscopic ligation of varices, TIPS and liver transplantation.

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Quality assurance in gastrointestinal endoscopy, as a crucial diagnostic and therapeutic process in medical care, has become a matter of increasing interest. However, concrete measures and standards are still lacking. Quality assurance as "continuous improvement" and "improvement by inspection" are discussed. Examples for clinical measures in the fields of indication for endoscopy, accuracy to the diagnostic test, thoroughness of the procedure and assessment of complications are given, and educational problems are discussed. Such structural problems of quality assurance as handling of a vast amount of data and assessment of late complications by follow-up information are addressed. Electronic data processing seems to be the most economic way to solve these problems. Requirements to data processing in the view of quality assurance are defined. Transferral of data from other departments within a hospital information system is necessary for the assessment of long-term follow-up. Different methods of communication within a hospital information system are discussed.

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Diarrhoea may occur in up to 10% of patients with ulcerative colitis treated with olsalazine, the azolinked dimer of 5-aminosalicylic acid. However, this symptom often disappears despite continued drug medication. To examine reversibility of and adaptation to olsalazine effects on intestinal absorption, rats were fed olsalazine (4 mg/100 g body weight/day) for 0 (controls), 12, 24, and 32 days. Jejunal, ileal, and colonic loops were perfused in situ with buffer or olsalazine (11.6 mM) in a pendular perfusion system. Water and electrolyte absorption was inhibited in all intestinal segments (p less than 0.001). In the proximal small intestine, however, sodium absorption was inhibited by 61%, whereas chloride and potassium absorptions were turned into net secretion. In contrast, in ileal and colonic segments sodium, chloride, and potassium absorptions were turned into a net secretion. All inhibitory effects were reversible within a short time. Intestinal absorption remained inhibitable compared with controls (p = not significant) after chronic administration of olsalazine even for 1 month. Jejunal monosaccharide absorption was not altered by acute olsalazine perfusion. In the ileum, glucose absorption was significantly inhibited, but the inhibitory capacity of acute olsalazine application decreased significantly (p less than 0.05) depending on duration of olsalazine pretreatment (51% (controls) versus 38% (32 days)). These results point to a complex, acute, but fully reversible effect of olsalazine on intestinal passive and chloride-coupled absorptive processes. Since a mucosal adaptation to these diarrheogenic effects does not occur, the resulting increase in fluid load on the diseased colon may be important in the pathogenesis of olsalazine-related diarrhoea.

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Beneficial effects of ursodeoxycholic acid in chronic cholestatic liver diseases have been attributed to displacement of hydrophobic bile acids from the endogenous bile acid pool. To test this hypothesis, we determined pool sizes, fractional turnover rates, synthesis/input rates and serum levels of deoxycholic acid and chenodeoxycholic acid before and 1 mo after the start of treatment with ursodeoxycholic acid (13 to 15 mg/kg body wt/day) in four healthy volunteers and five patients with chronic cholestatic liver diseases (three with primary biliary cirrhosis and two with primary sclerosing cholangitis). Bile acid kinetics were determined by combined capillary gas chromatography-isotope ratio mass spectrometry in serum samples after administration of [2H4] deoxycholic acid and [13C]chenodeoxycholic acid. In healthy volunteers, deoxycholic acid pool sizes decreased during administration of ursodeoxycholic acid by 72%. In patients with cholestatic liver diseases, deoxycholic acid pool sizes before ursodeoxycholic acid treatment were only 13% of those in healthy volunteers and were unaffected by ursodeoxycholic acid treatment. Chenodeoxycholic acid pool sizes were not different in healthy volunteers and in patients with cholestatic liver disease, and were not altered by ursodeoxycholic acid treatment. In both healthy volunteers and patients with cholestatic liver disease, synthesis/input rates and serum levels of deoxycholic acid and chenodeoxycholic acid were not altered by ursodeoxycholic acid treatment. Because in our patients improvement of serum liver tests during short-term ursodeoxycholic acid treatment was noted without a decrease of the pool sizes of the major hydrophobic bile acids, we conclude that displacement of hydrophobic endogenous bile acids is not the mechanism of action of ursodeoxycholic acid in chronic cholestatic liver disease.

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Metabolic substrates such as octanoate, beta-hydroxybutyrate, and alpha-ketoisocaproate which produce acetoacetate stimulate the rate of pyruvate decarboxylation in perfused livers from fed rats at perfusate pyruvate concentrations in the physiological range (below 0.2 mM). A quantitative relationship between pyruvate oxidation (14CO2 production from [1-14C]pyruvate) and ketogenesis (production of acetoacetate or total ketone bodies) was observed with all ketogenic substrates when studied over a wide range of concentrations. The ratio of extra pyruvate decarboxylated to extra acetoacetate produced was greater than 1 with octanoate and alpha-ketoisocaproate, but it was less than 1 with beta-hydroxybutyrate. The stimulatory effect of beta-hydroxybutyrate on pyruvate decarboxylation was abolished completely in the presence of 0.1 mM alpha-cyanocinnamate, an inhibitor of the pyruvate transporting system in the mitochondrial membrane. The data suggest that the mechanism by which the flux through the pyruvate dehydrogenase reaction is stimulated in liver under ketogenic conditions involves an acceleration of the net rate of pyruvate transport into the mitochondria compartment due to an exchange with acetoacetate and/or acetoacetate plus beta-hydroxybutyrate.

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