[Mesenchymal gastric tumor--not always GIST]. / Mesenchymaler Magentumor--nicht immer GIST.

The correct histopathological classification of a gastric mesenchymal tumor as a schwannoma is essential because in contrast to gastrointestinal stromal tumors (GIST) it is a definitive benign neoplasm which can be sufficiently treated by in sano (R0) resection. A (partial) gastrectomy is unnecessary. A clear radiological or sonographical differentiation between a schwannoma and GIST is not possible. The histomorphological and immunohistochemical features of this tumor entity are described.

Computed virtual chromoendoscopy versus standard colonoscopy with targeted indigocarmine chromoscopy: a randomised multicentre trial.

OBJECTIVE: Colonoscopy is the accepted gold standard for screening of neoplastic colorectal lesions, but the substantial miss rate remains a challenge. Computed virtual chromoendoscopy with the Fujinon intelligent colour enhancement (FICE) system is a new dyeless imaging technique that might allow higher rates of adenoma detection. METHODS: This is a prospective randomised five tertiary care centre trial of colonoscopy in the FICE mode versus standard colonoscopy with targeted indigocarmine chromoscopy (control group) in consecutive patients attending for routine colonoscopy. Histopathology of detected lesions was confirmed by evaluation of endoscopic resection or biopsy specimens. RESULTS: 871 patients were enrolled, and 764 patients (344 female, mean age 64 years) were subjected to final analysis (368 in the FICE group, 396 in the control group). In total, 236 adenomas (mean of 0.64 per case) were detected in the FICE group and 271 adenomas (mean of 0.68 per case) in the control group (p = 0.92). There was no statistically significant difference in the percentage of patients with >or=1 adenoma between the control group (35.4%) and the FICE group (35.6%) (p = 1.0). For the differential diagnosis of adenomas and non-neoplastic polyps, the sensitivity of FICE (92.7%) was comparable with that of indigocarmine (90.4%) (p = 0.44). CONCLUSIONS: At colonoscopy, adenoma detection rates are not improved by virtual chromoendoscopy with the FICE system compared with white light endoscopy with targeted indigocarmine spraying. However, FICE can effectively substitute for chromoscopy concerning the differentiation of neoplastic and non-neoplastic lesions.

Low frequency of colorectal dysplasia in patients with long-standing inflammatory bowel disease colitis: detection by fluorescence endoscopy.

BACKGROUND AND STUDY AIM: Patients with long-standing inflammatory bowel disease (IBD) have an increased risk of developing colonic dysplasias. Dysplastic changes in flat mucosa are likely to be missed by conventional colonoscopy. Endoscopic fluorescence imaging, using 5-aminolevulinic acid (5-ALA) as photosensitizer, has evolved as a new technique to differentiate between normal colonic mucosa and dysplasia. We combined this technique with random biopsies to prospectively evaluate the occurrence of dysplasias in patients with long-standing IBD. PATIENTS AND METHODS: 52 colonoscopies were performed in 42 consecutive patients (n = 28 with ulcerative colitis, n = 11 with Crohn's colitis, n = 3 with indeterminate colitis; mean age 43 years, range 21 - 78) with long-standing IBD colitis (median disease duration 14 years, range 3 - 40). All patients were in clinical remission. Patients were examined using both conventional white light and by fluorescence colonoscopy using oral 5-ALA. Four biopsies were taken every 10 cm from mucosa of normal appearance. In addition, macroscopically suspicious and fluorescence-positive areas were biopsied. RESULTS: A total of 688 biopsies of red-fluorescent (n = 20) and nonfluorescent (n = 662) areas of mucosa were taken. Dysplasia was detected histopathologically in only two of the biopsies. These biopsies were taken from two polypoid lesions which were fluorescence-negative. CONCLUSIONS: The rate of colonic dysplasia in patients with long-standing IBD colitis may be lower than previously reported.

Crohn disease of the small bowel proximal to the terminal ileum: detection by MR-enteroclysis.

BACKGROUND: Although Crohn disease (CD) can affect the entire alimentary tract, the proportion of patients with small-bowel inflammation proximal to the terminal ileum is still unclear. Magnetic resonance imaging (MRI) combined with small-bowel enteroclysis can detect inflammatory lesions of the small bowel. Hence, we applied MR-enteroclysis to assess the percentage of patients with small-bowel inflammation proximal to the terminal ileum among patients with CD and abdominal pain. METHODS: Twenty-five consecutive patients with low, active CD of the colon and/or terminal ileum and episodes of abdominal pain were examined by both MR-enteroclysis and conventional enteroclysis. The findings of MR-enteroclysis were compared with endoscopic and histological results in the terminal ileum and conventional enteroclysis in the small bowel proximal to the terminal ileum. RESULTS: In 13 of the 25 patients, inflammation of the small bowel proximal to the terminal ileum was shown by MR-enteroclysis, whereas in only 4 of the 25 patients, signs of inflammation of the small bowel proximal to the terminal ileum were shown by conventional enteroclysis, all of which were demonstrated by MR-enteroclysis. MR-enteroclysis confirmed the findings in 22 of 25 patients in whom endoscopy and histology had shown inflammation (16 of 18) or no inflammation (6 of 7) of the terminal ileum. CONCLUSION: In symptomatic patients with CD even of low activity, inflammation of the small bowel proximal to the terminal ileum is frequent.

[Inflammatory bowel diseases (IBD) -- critical discussion of etiology, pathogenesis, diagnostics, and therapy]. / Chronisch entzündliche Darmerkrankungen -- Kritische Diskussion von Atiologie, Pathogenese, Diagnostik und Therapie.

AIMS: Crohn's disease and ulcerative colitis are the most frequent inflammatory bowel diseases (IBD) with a prevalence of approximately one out of 500. Cytokine research opened new and potent treatment options and thus stimulated clinical and basic research.However, the IBD still remain a challenge for patients and physicians,demanding close cooperation between gastroenterologists,radiologists and surgeons. The basic understanding of IBD,which is necessary for efficient diagnostic and therapeutic concepts is reviewed. METHODS: Based upon recent publications and our clinical experience we discuss aspects of etiology,pathogenesis,diagnostics,and therapy of Crohn's disease and ulcerative colitis. RESULTS: A genetically influenced, exaggerated and sustained immune response against the own gut flora seems to be one of the most important factors in the pathogenesis of IBD. Not less important are environmental influences. For instance, cigarette smoking had been judged to have some negative influence on the natural course of Crohn's disease.Now,however, recent studies show that smoking is even a significant independent risk factor in the pathogenesis of IBD. Since IBD and especially Crohn's disease can effect the whole body, detailed analysis of inflammatory organ involvement is necessary before therapy. For instance, the MRI enteroclysis technique adds a necessary diagnostic tool for the exploration of those parts of the small bowel that cannot been reached by routine endoscopy like the upper ileum and the lower jejunum. In terms of therapy, a change of paradigms can be observed: patients will no longer be treated only when symptoms arise, but will early be integrated into a therapeutic concept, which is determined by site and extent of the disease and adapted to the abilities and needs of the patient.Furthermore,immunosuppressive agents like azathioprine and 6-mercaptopurine will establish as central concept in the medical treatment of IBD. DISCUSSION: IBD-therapy should rather be adapted to the patient's individual inflammatory pattern than be oriented to schematic treatment rules. New endoscopic and radiologic techniques provide the necessary diagnostic tools.

Tele-endoscopy: influence of data compression, bandwidth and simulated impairments on the usability of real-time digital video endoscopy transmissions for medical diagnoses.

BACKGROUND AND STUDY AIMS: Real-time digital video transmission (rtDVT) at an acceptable quality through networks has been possible for several years. This technique can be used for telemedical applications, such as tele-endoscopy. The hypotheses of the present study were that the quality of real-time DVT depends on the technical equipment used, and that the resulting image quality influences the usability of the system for diagnostic purposes. MATERIALS AND METHODS: An experimental network was established between two German referral endoscopy centers, using the Asynchronous Transfer Mode (ATM) protocol. At first, rtDVTs of routine gastrointestinal video endoscopies were transferred through the network for prospective evaluation of the feasibility of the technical equipment and its usability for diagnostic tele-endoscopy, based on the video image quality. Secondly, the image quality and usability for correct telemedical diagnosis were evaluated prospectively in a double-blind experimental setting in relation to variations in the methods of data compression used, transmission bandwidths, and simulated transmission errors. Fourteen endoscopists evaluated 27 variations of an endoscopic video sequence. RESULTS: Compression with the Moving Picture Expert Group 2 (MPEG2 [4 : 2 : 2]) standard, the ATM protocol, and a bandwidth of 40 megabits per second (Mb/s) were used successfully in 40 routine tele-endoscopies for practical evaluation. Doctors were able to handle the system with ease, and its availability was 100%. There were no detectable differences between the original video image and the transferred image, and the images were usable for diagnosis in all cases. The set-up used clinically was therefore considered to provide the optimal conditions for comparisons in the experimental part of the study. Experimentally, any technical variation was found to cause a reduction in the overall image quality and hence a reduction in diagnostic usability: compression algorithm (MPEG2 [4 : 2 : 2] vs. others: P = 0.001), bandwidth (> or = 8 vs. < 8 Mb/s: P = 0.001), and error rate (10 (-8) vs. 10 (-7): P = 0.001). CONCLUSIONS: rtDVT using MPEG2 [4 : 2 : 2] compression and a bandwidth of 40 Mb/s did not effectively differ from the original video images in routine tele-endoscopy. The qualitative requirements in diagnostic video endoscopy, however, are obviously much higher than previously assumed, since experienced endoscopists detected a loss of image quality and a reduction in diagnostic usability with any reduction in the technical specification. Modern methods of data compression, broadband networks and a network protocol with good quality-of-service guarantees are therefore prerequisites for diagnostic rtDVT.

[Surgical therapy of locally advanced and primary inoperable pancreatic carcinoma after neoadjuvant preoperative radiochemotherapy]. / Chirurgische Therapie des lokal fortgeschrittenen und primär inoperablen Pankreaskarzinoms nach neoadjuvanter präoperativer Radiochemotherapie.

INTRODUCTION: So far, surgery represents the only prospect for cure in patients with pancreatic cancer. Most patients, however, present with locally advanced pancreatic cancer at primary diagnosis. Recently, novel therapeutic regimens with preoperative radiochemotherapy have been developed that may improve long-term survival and resectability rates of patients with locally advanced pancreatic cancer. METHODS: This feasibility study evaluates the preliminary results of neoadjuvant therapy with gemcitabine and 5-fluorouracil (5-FU) or cisplatin. Twenty-six patients suffering from locally advanced pancreatic cancer were considered for preoperative radiochemotherapy. They received radiation (45 Gy) and chemotherapy with simultaneous or sequential gemcitabine and 5-FU (n = 15) or gemcitabine and cisplatin (n = 11) administration prior to surgical resection. RESULTS: Mean patient age was 62.4 +/- 2.6 years and 62% (n = 16) were male. The response rate was 69%, and 11 patients underwent curative surgical resection of the pancreatic cancer. Nine Whipple procedures and two complete pancreatectomies were carried out. In five patients a total of eight surgical complications were observed. Median overall survival was 9.8 months after primary cancer diagnosis (mean 12.0 +/- 1.2). During follow-up no local recurrent disease was detected. CONCLUSIONS: Our findings lead us to conclude that preoperative chemoradiation with 45 Gy, gemcitabine and 5-FU or cisplatin is a powerful therapeutic tool in patients with locally advanced non-resectable pancreatic cancer. Major resections, including vascular reconstructions, are nonetheless associated with increased mortality. Preoperative chemoradiation contributes to improved survival in patients with primary non-resectable pancreatic cancer.

[Screening for prevention of colorectal carcinoma. Who, when, how?]. / Screening zur Vorbeugung des kolorektalen Karzinoms. Wer, wann, wie?

Long-term survival of patients with colon carcinoma is largely determined by the timing of the diagnosis. For the identification of early colorectal carcinoma, it is of particular importance to detect and remove local precursor lesions (polyps) by means of effective screening, before they undergo malignant degeneration. The gold standard for such screening continues to be colonoscopy, followed by sigmoidoscopy, which latter, however, leaves large segments of the proximal uninspected. Additional--though less sensitive and more complicated--current screening techniques are the test for occult blood in the stools and the barium Doppler contrast examination, and, possibly in the near future, virtual colonoscopy and genetic testing for tumor DNA in the stools. Detailed screening recommendations are to be found in the guidelines issued by the German Society for Digestive and Metabolic Diseases. A prerequisite for effective prevention of colorectal carcinoma is the provision of information to, and motivation of, both the population and the individual patient, to participate in screening measures.

Extracorporeal shock wave lithotripsy for clearance of bile duct stones resistant to endoscopic extraction.

BACKGROUND: Endoscopic extraction of bile duct stones after sphincterotomy has a success rate of up to 95%. Failures occur in patients with extremely large stones, intrahepatic stones, and bile duct strictures. This study examined the efficacy and the safety of extracorporeal shock-wave lithotripsy in a large cohort of patients in whom routine endoscopic measures including mechanical lithotripsy had failed to extract bile duct stones. METHODS: Out of 1587 consecutive patients, endoscopic stone extraction including mechanical lithotripsy was unsuccessful in 313 (20%). These 313 patients (64% women, median age, 73 years) underwent high-energy extracorporeal shock-wave lithotripsy. Stone targeting was performed fluoroscopically (99%) or by ultrasonography (1%). RESULTS: Complete clearance of bile duct calculi was achieved in 281 (90%) patients. In 80% of the patients, the fragments were extracted endoscopically after shock-wave therapy; spontaneous passage was observed in 10%. For patients with complete clearance compared with those without there were no differences with regard to size or number of the stones, intrahepatic or extrahepatic stone location, presence or absence of bile duct strictures, or type of lithotripter. Cholangitis (n = 4) and acute cholecystitis (n = 1) were the rare adverse effects. CONCLUSIONS: In patients with bile duct calculi that are difficult to extract endoscopically, high-energy extracorporeal shock-wave lithotripsy is a safe and effective therapy regardless of stone size, stone location, or the presence of bile duct stricture.

[Virtual large intestine imaging with multi-level CT. Pain free coloscopy--that works!]. / Virtuelle Dickdarmspiegelung mit der Mehrschicht-CT. Schmerzfrei koloskopieren--das geht!

Provided that the bowel is carefully cleansed, virtual colonoscopy permits a safe, reliable and painfree diagnosis of the large bowel. It requires distension of the bowel with ambient air. Contraindications include pregnancy, acute inflammation of the bowel and recent surgery. Tumors and large polyps (10 mm and more) can be diagnosed with certainty, while polyps measuring 5 mm and more are detected with a high degree of sensitivity. It goes without saying that virtual colonoscopy does not allow for the taking of biopsy material or the performance of therapeutic measures, so that positive or suspicious findings must be clarified by conventional colonoscopy. In principle, virtual colonoscopy is also suitable for use as a screening procedure. Whether the radiation exposure associated with the conventional examination protocol can be considered acceptable for screening purposes is questionable. However, using mathematical means, the radiation dose can be reduced to one-tenth of the usual dose.

[75-year-old patient with persistent abdominal complaints and vomiting during a cruise]. / 75-jährige Patientin mit persistierenden abdominellen Beschwerden und Erbrechen während einer Kreuzfahrt.

BACKGROUND: In elderly patients with gallstone disease, a gallstone ileus must be considered for unexplained abdominal pain. This is demonstrated in the following case report. CASE REPORT: A 75-year-old female patient presented with a 72-hour history of abdominal pain, nausea and vomiting. The patient's abdomen was mildly distended, although soft and nontender with bowel sounds present. Plain radiographs and ultrasound investigation of the abdomen were compatible with small bowel obstruction. To clarify the etiology, an abdominal computed tomography scan was obtained. These examinations disclosed air in the biliary tree, dilated small bowel and an impacted intraluminal abnormality in the terminal ileum compatible with a gallstone. Operative intervention confirmed the presence of a 3 cm obstructing calculus in the terminal ileum that was removed by an enterolithotomy. A two-step cholecystectomy and closure of the cholecystoduodenal fistula were performed 8 weeks later. The patient's recovery was uneventful. CONCLUSIONS: Although rare in a general population, gallstone ileus accounts for 25% of nonstrangulated small bowel obstructions in patients over the age of 65. The radiographic picture and ultrasound of small bowel obstruction and the presence of air in the biliary tree are suggestive for the diagnosis of a gallstone ileus. In our patient, the computed tomography and ultrasound findings confirmed the diagnosis and led to a prompt and directed surgical intervention. In patients with comorbid factors a two-step approach with enterolithotomy in a first and cholecystectomy in a second operation should be the therapeutic strategy of choice.

Colonic mucosal proliferation is related to serum deoxycholic acid levels.

BACKGROUND: Hyperproliferation of the colorectal mucosa is regarded as an early step in colorectal carcinogenesis. Deoxycholic acid, a secondary bile acid, stimulates colorectal epithelial proliferation in animals and is considered a tumor promoter in human colorectal carcinogenesis. The aim of this study was to investigate the correlation between colorectal mucosal proliferation and the serum deoxycholic acid level. METHODS: From each of 19 patients (10 men and 9 women) with (n = 3) or without (n = 16) colorectal adenoma, 18 biopsy specimens were obtained by colonoscopy, 3 from each of the 6 colonic segments. A crude nuclei fraction was prepared, and DNA was stained by propidium iodide to determine the proliferative index (the percentage of cells in the S and G2/M phases of the cell cycle) by flow cytometry. Serum levels of deoxycholic acid were determined by gas-liquid chromatography. RESULTS: The colonic proliferation rates (median of the values obtained in all segments, 14.1%; range, 10.0-18.7%) and the fasting serum deoxycholic acid levels (median, 0.86 micromol/L; range, 0.28-1.58 micromol/L) showed a significant correlation (r = 0.51, P = 0.03). Serum lithocholic, cholic, chenodeoxycholic, and ursodeoxycholic acid levels were not correlated with the proliferation rates. CONCLUSIONS: Levels of deoxycholic acid in serum are correlated with the rates of the colorectal mucosa. These results are consistent with the concept that deoxycholic acid promotes colorectal carcinogenesis.

Detection of colonic dysplasia by light-induced fluorescence endoscopy: a pilot study.

Light-induced fluorescence endoscopy (LIFE) has been shown to differentiate between normal mucosa and dysplastic lesions, and dysplastic lesions of the colon occult to routine white-light colonoscopy may thus be visualized by LIFE. We compared the sensitivity and specificity of LIFE to routine white-light colonoscopy in patients with colonic dysplasia. In a pilot study 20 patients with colonic adenoma, inflammatory bowel disease, or with a history of colon cancer were screened for colonic dysplasia during routine colonoscopy. Forty-two sites of mucosal abnormalities regarded as suspicious for dysplasia during white-light colonoscopy were additionally examined with a prototype LIFE system. Biopsies were taken from all 42 colonic sites. The LIFE images were classified as positive or negative for dysplasia. Sensitivity and specificity were calculated by correlating positive and negative findings to the histopathological results. Histopathology detected 21 adenomas with low-grade dysplasia and one with high-grade dysplasia. All dysplastic lesions were found by routine white-light endoscopy. The specificity of conventional white-light endoscopy was 80%. Of the 22 dysplastic lesions 20 were detected by LIFE (sensitivity 91%). The specificity of LIFE was 90% (two false-positive results). LIFE combined with conventional endoscopy may thus improve the detection of colonic dysplasia.