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M Cremer

Publications and source records attributed to M Cremer.

At least 55 records · Page 3Linked to original sources

Relative contribution of Ki-ras gene analysis and brush cytology during ERCP for the diagnosis of biliary and pancreatic diseases.

BACKGROUND: Ki-ras mutation analysis from material collected during ERCP has been claimed to improve the diagnosis of pancreatic and bile duct carcinomas as compared with conventional cytology. Our aim was to study the relative contribution of both Ki-ras analysis and brush cytology in patients with a significant stricture at ERCP. METHODS: Brushings were collected in duplicate for both analyses in 142 patients in whom a definitive diagnosis was obtained by histology or a minimal follow-up of 6 months. RESULTS: For pancreatic strictures, sensitivity, specificity, and accuracy of Ki-ras analysis vs. cytology in detecting malignancy were 81% vs. 66%, 72% vs. 100%, and 70% vs. 74%, respectively. For biliary strictures, they were 25% vs. 42%, 100% vs. 100%, and 35% vs. 43%, respectively. The combination of the two methods only marginally increased their sensitivity and accuracy in both types of strictures. CONCLUSION: Ki-ras analysis is a sensitive method for diagnosing pancreatic but not biliary carcinoma. However, its specificity is lowered by a high frequency of Ki-ras mutations in patients with chronic pancreatitis (25%) who did not manifest cancer development within a 6-month follow-up period. In pancreatic duct strictures, brush cytology appears to be more specific in detecting malignancy; specificity for Ki-ras and cytology are equivalent for the diagnosis of malignant bile duct strictures. Therefore, making a clinical decision on the sole basis of Ki-ras analysis is probably not justified in the majority of the cases.

Adult↗

Plastic and metal stents for postoperative benign bile duct strictures: the best and the worst.

BACKGROUND: Endoscopic treatment of postoperative benign bile duct strictures (BBDS) is technically challenging, and the long-term outcome after stricture dilation remains poorly defined. METHODS: Forty-eight cases of postoperative BBDS with attempted endoscopic treatment (either transient plastic stenting or definitive metal stent insertion) were reviewed. RESULTS: Endoscopic stricture dilation succeeded in 47 of 48 cases (98%). No procedure-related mortality was observed; 16 (33%) procedure-related or stent-associated complications were observed during treatment. Endoscopic treatment was interrupted in five patients. Stricture relapse occurred in 6 of 6 (100%) and 7 of 36 (19%) patients after metal stent insertion and plastic stent removal, respectively (p < 0.001) (mean follow-up periods 50+/-12 and 44+/-34 months, respectively). After plastic stent removal, stricture relapses were more frequent among patients with strictures related to liver transplantation as opposed to other surgical procedures (p < 0.05); these recurrent strictures were successfully treated by repeated insertion of plastic stents on a temporary basis. At the end of follow-up, all but one patient treated with plastic stents had normal serum alkaline phosphatase values. CONCLUSION: Metal stents proved to be inadequate for treating postoperative BBDS. Temporary insertion of a plastic stent (possibly repeated) provided long-term results equal or superior to those reported for surgical biliary drainage. Repeated insertion of plastic stents was more frequently indicated for strictures related to liver transplantation compared with other surgical procedures.

Adult↗

Intraductal papillary and mucinous tumors of the pancreas: accuracy of preoperative computed tomography, endoscopic retrograde pancreatography and endoscopic ultrasonography, and long-term outcome in a large surgical series.

BACKGROUND: Few data are available on the accuracy of preoperative imaging or on long-term outcome after surgery for intraductal papillary and mucinous tumors of the pancreas. The aims of this study were to assess the following: (1) the accuracy of preoperative computed tomography, endoscopic retrograde pancreatography, and endoscopic ultrasonography for determination of tumor invasion and pancreatic extension as compared with surgical findings; (2) the long-term outcome after surgery. METHODS: Forty-seven patients who underwent surgery between 1980 and 1995 for pathologically diagnosed intraductal papillary and mucinous tumors were included in this study. The findings of available computed tomography (n = 25), endoscopic retrograde pancreatography (n = 29), and endoscopic ultrasonography (n = 21) were reviewed by experienced clinicians blinded to pathologic diagnosis to assess tumor invasion and pancreatic extension. Pathologic specimens were reviewed by experienced pathologists. Postoperative follow-up data were analyzed. RESULTS: Histologic features of invasive carcinoma were found in 43% of patients, severe dysplasia in 21%, and mild or moderate dysplasia in 36%. The overall accuracy of computed tomography, endoscopic retrograde pancreatography, and endoscopic ultrasonography in distinguishing between invasive and noninvasive tumors were, respectively, 76%, 79%, and 76%. The overall 3-year disease-free survival rate was 63%, but it was 21% among patients with invasive carcinoma at surgery (p < 0.001). CONCLUSIONS: This study emphasizes the need for early surgical resection in patients with suspected intraductal papillary and mucinous tumors of the pancreas because of the high frequency of invasive carcinoma and the inadequacy of preoperative imaging for assessing malignancy.

Adenocarcinoma, Mucinous↗

Dissolution of gallbladder stones with methyl tert-butyl ether and stone recurrence: a European survey.

Since there are now several ways to treat symptomatic gallstone disease, one is able to select treatment on the basis of the patient's comfort, the practicability, effectiveness, and side effects of the technique, and the relative costs. In order to assess the present status of contact dissolution with methyl tert-butyl ether with regard to these aspects, the present enquiry reports the data of 21 European hospitals. Eight hundred three patients were selected for contact litholysis of cholesterol gallbladder stones using methyl tert-butyl ether. Percutaneous transhepatic puncture of the gallbladder was performed under x-ray or ultrasound guidance. Dissolution rate, side effects, and treatment times of 268 patients from one single center were compared to those of 535 patients from the other 20 centers. Two hundred sixty-four patients were followed for five years to assess stone recurrence. Physicians were asked how they assessed the expenditure of the method, the discomfort to the patients, and the staffing situation. Patients were asked to indicate their acceptance on an analog scale. Puncture was successful in 761 (94.8%) patients. Prophylactic administration of antibiotics was not necessary. Stones were dissolved in 724 (95.1%) patients. In 315 (43.5%) sludge remained in the gallbladder. The most severe complication was bile leakage, which led 12 (1.6%) patients to have elective cholecystectomy. Toxic injuries due to the ether were not reported. Method-related lethality amounted to 0%, 30-day-lethality to 0.4%. Stone recurrence rate was about 40% in solitary stones and about 70% in multiple stones over five years. Patients with multiple stones developed recurrent stones almost twice as often as those with solitary stones. The probability of stone recurrence in patients with sludge in the gallbladder after catheter removal was not statistically significantly different from those without sludge. Seventy to 90% of the centers found the puncture to be simple and not distressing for patients and the relation between expenditure and therapeutic success to be acceptable. The acceptance of contact litholysis by the patients was excellent. Contact litholysis when applied by an experienced team provides real advantages in the treatment of gallstone disease. The method is technically simple, well accepted by the patients, and can be easily applied in community hospitals. Contact litholysis may be of particular value in patients who are not suitable for anesthesia or surgery.

Adolescent↗

The wirsungorrhagies: causes and management in 14 patients.

BACKGROUND AND STUDY AIMS: Wirsungorrhagy is an extremely rare cause of upper gastrointestinal bleeding. The present study describes 14 cases observed over a seven-year period. MATERIAL AND METHODS: Among 10,000 endoscopic retrograde cholangiopancreatographies performed between 1989 and 1996 we have identified 14 wirsungorrhagies, which were reviewed retrospectively. They occurred in patients with chronic and acute pancreatitis, and primary and metastatic pancreatic cancer. RESULTS: Clinical signs of bleeding were present in six patients; three other patients had occult blood loss, and in five patients wirsungorrhagy was caused by endoscopic manipulation (n=3) or extracorporeal shock-wave lithotripsy (n=2) without clinical or hemodynamic effects. In six patients, wirsungorrhagy was managed by endoscopic methods. Five patients in unstable clinical conditions had an arteriography which allowed identification and treatment of the source of bleeding in three cases. Two patients with bleeding from a communicating cyst in chronic pancreatitis underwent surgery. CONCLUSIONS: Wirsungorrhagy can be responsible for massive bleeding in certain patients, especially those with chronic pancreatitis and pseudoaneurysm. In these cases, arteriography is most useful for identification and treatment of the bleeding. When it occurs during endoscopic manipulations, it can usually be managed endoscopically and/or stops spontaneously with appropriate main pancreatic duct drainage. When it occurs in patients with pancreatic tumors, optimal treatment is surgical resection; this is, unfortunately, usually not feasible.

Acute Disease↗

Eradication of Barrett's mucosa with argon plasma coagulation and acid suppression: immediate and mid term results.

BACKGROUND: Intestinal metaplastic mucosa in Barrett's oesophagus can be replaced by squamous epithelium after mucosal thermal ablation associated with acid suppression therapy. AIMS: To assess whether restoration of squamous epithelium can be obtained after ablation of Barrett's oesophagus using argon plasma coagulation (APC) associated with proton pump inhibitor (PPI) therapy. METHODS: Thirty one patients with Barrett's oesophagus received APC. Omeprazole (40 mg/day) was given from the first APC application to one month after completion of the treatment, then given symptomatically. Twenty four hour pH-metry was performed during endotherapy. RESULTS: Complete re-epithelialisation was visualised at endoscopy in 25/31 patients (81%) after a mean number of 2.4 APC sessions (range 1-4). Only partial squamous re-epithelialisation was observed in three patients and three others had no eradication. At histological assessment, eradication of Barrett's oesophagus was only confirmed in 19/31 patients (61%) due to the presence of a few residual Barrett's glands under the new squamous epithelium. Complete eradication was related to a Barrett's oesophagus segment length of less than 4 cm and the absence of circumferential extension but not to the normalisation of oesophageal acid exposure under PPI therapy. Seventeen patients with apparently complete endoscopic and histological eradication of Barrett's oesophagus were re-evaluated at one year; eight (47%) disclosed relapsing islands of Barrett metaplasia despite continuous omeprazole therapy (10-40 mg/day). CONCLUSIONS: APC combined with 40 mg omeprazole daily can eradicate Barrett's mucosa with apparent squamous re-epithelialisation in the majority of patients even in the absence of normalisation of oesophageal acid exposure. However, one year after endotherapy for Barrett's oesophagus, relapse is frequent but limited in extent.

Adult↗

Choledochal cysts: comparison of findings at MR cholangiopancreatography and endoscopic retrograde cholangiopancreatography in eight patients.

PURPOSE: To compare prospectively the data provided with endoscopic retrograde cholangiopancreatography (ERCP) and magnetic resonance (MR) cholangiopancreatography (MRCP) in eight patients with symptomatic choledochal cysts. MATERIALS AND METHODS: Eight patients (three children, five adults) with choledochal cyst and abdominal pain underwent sequential single-shot turbo spin-echo T2-weighted MRCP and ERCP. Seven of the eight patients had relapsing pancreatitis. In three patients, a dynamic MR examination was performed after secretin stimulation of exocrine pancreatic function. RESULTS: A complete correlation was observed between ERCP and MRCP for defining the anatomic characteristics of the cyst (seven type I cysts, one type IV cyst) and the presence of an abnormal pancreaticobiliary junction (PBJ) (six patients) with a long common channel. Of the seven patients with acute pancreatitis, six had an abnormal PBJ and one had common bile duct (CBD) stones with a normal ductal union evidenced with both techniques. In two patients, dynamic MRCP demonstrated preferential filling of the gallbladder and the CBD after secretin injection, whereas normal duodenal filling was observed in another patient without a junctional abnormality. CONCLUSION: MRCP provides information equivalent to that provided with ERCP, without potential complications, for the preoperative assessment of choledochal cysts. Dynamic secretin-stimulated MRCP studies might help better understand the pathophysiologic characteristics of this entity.

Adolescent↗

Acinar filling during secretin-stimulated MR pancreatography.

OBJECTIVE: The purpose of this study is to report a new sign, "acinar filling," observed on dynamic MR pancreatography after secretin stimulation in patients with suspected early chronic pancreatitis. CONCLUSION: Acinar filling might reflect tissue hypertension or loss of pancreatic parenchyma compliance or both. This finding is probably an insensitive but specific sign of early chronic pancreatitis.

Aged↗

Pancreatic duct stones management.

Pancreatic stone formation is characteristic of chronic pancreatitis. Ductal obstruction is a major cause of pain and the principal disabling symptom of the disease. This article briefly reviews the pathophysiology of pancreatic stone formation and describes the current nonsurgical range of therapeutic modalities.

Calculi↗

[Intraductal papillary mucinous tumors of the pancreas: are there any preoperative clinical and laboratory factors predictive of degeneration. Results of a French-Belgium collective series].

Intraductal papillary and mucinous tumors are rare. We retrospectively analysed clinical, surgical and histological features and outcome of 41 operated patients (29 males, 12 females, mean age = 63 years). The commonest presenting manifestation was acute pancreatitis (41%). Tumor was located in only one pancreatic segment in 45% cases. Forty one per cent of patients had invasive carcinoma, 20% had tumor with severe dysplasia and 39% with minimal or moderate dysplasia. Only elevated age was significantly associated with invasive carcinoma. Eleven out of 17 patients with invasive carcinoma (65%) had a recurrence after surgery and 6 (35%) died. Among 24 patients with noninvasive tumor, 2 (8%) recurred without tumor-related death in the follow-up (48 months). This study underlines the need for early surgical resection in patients with intraductal papillary and mucinous tumor because of the high frequency of invasive carcinoma and the poor outcome of patients with invasive carcinoma.

Adenocarcinoma, Mucinous↗

Myotonic dystrophy. The role of large triplet repeat length in the development of mental retardation.

OBJECTIVE: To describe mental retardation and microcephaly as initial clinical signs in myotonic dystrophy (MD) with high trinucleotide repeats. PATIENTS AND METHODS: Two patients with maternally inherited MD were examined. Southern blot analysis was performed and trinucleotide repeat expansions were related to the findings of clinical and magnetic resonance imaging investigations. RESULTS: Both patients had the large CTG trinucleotide repeat expansions often seen in congenital MD, but they lacked the typical clinical signs. Mental retardation and microcephaly were the leading features present in infancy. Muscular weakness, in contrast, developed after age 35 years. Although there was no evidence for perinatal asphyxia or sleep apnea, magnetic resonance imaging disclosed reduced brain volume and subcortical demyelination. CONCLUSIONS: Mental retardation preceding the development of muscle weakness suggests that the cerebral involvement in MD is a direct consequence of the genetic disorder and not mediated by muscle disease. Careful clinical examination of the parents for signs of MD should be considered in patients with cognitive deficits even without apparent muscular involvement.

Adult↗

High-resolution comparative hybridization to combed DNA fibers.

Comparative genomic hybridization (CGH) has proven to be a comprehensive new tool to detect genetic imbalances in genomic DNA. However, the resolution of this method carried out on normal human metaphase spreads is limited to low copy number gains and losses of > or = 10 Mb. An improved resolution allowing the detection of copy number representations of single genes would strongly enhance the applicability of CGH as a diagnostic and research tool. This goal may be achieved when metaphase chromosomes are replaced by an array of target DNAs representing the genes of interest. To explore the feasibility of such a development in a model system we used cosmid MA2B3, which encompasses about 35 kb in the vicinity of exon 48 of the human dystrophin gene. Linearized cosmid fibers were attached to a glass surface and aligned in parallel by "molecular combing". Two-color fluorescence in situ suppression hybridization was performed on these cosmid fibers with probe mixtures containing different ratios (ranging from 1:2 to 4:1) of biotin- and digoxigenin-labeled MA2B3 cosmid DNAs. For each mixture fluorescence ratios were determined for 40-50 individual combed DNA molecules. In two series comprising a total of 651 molecules the median fluorescence ratio measurements revealed a linear relationship with the chosen probe ratios. Our study demonstrates that fluorescence ratio measurements on single DNA molecules can be performed successfully.

Biotin↗

Endoscopic treatment of gastric outlet obstruction caused by a gallstone (Bouveret's syndrome) after extracorporeal shock-wave lithotripsy.

Two patients with gastric outlet obstruction caused by a gallstone were treated by endoscopic lithotripsy. All fragments of significant size were removed orally, except for one that was left in the stomach in the first patient. This fragment caused a recurrent ileus after initial clinical improvement. The other patient remained clinically well after hospital discharge.

Aged↗

Different expression of transforming growth factor beta 1 in pancreatic ductal adenocarcinoma and cystic neoplasms.

Pancreatic neoplasms harbor different prognoses according to their histological type: a benign course for serous cystadenoma, a low malignant potential for intraductal papillary mucinous neoplasms (IPMN), and high aggressiveness for ductal adenocarcinoma (ADC). Transforming growth factor beta 1 (TGF beta 1) may regulate tumor growth. The present study analyzes and compares the expression of its precursor beta 1-latency-associated peptide (beta 1-LAP), its latent binding protein (LTBP), and its mRNA in ductal adenocarcinoma (n = 10), in IPMN (n = 8), in serous cystadenoma (n = 2), and in normal tissues (n = 5). LTBP is thought to play a strategic role in the processing and active secretion of latent TGF beta 1 and its stockage in the extracellular matrix. Localization of beta 1-LAP and LTBP was assessed by immunohistochemistry using specific antibodies and expression of TGF beta 1 mRNA by reverse-transcriptase polymerase chain reaction analysis. beta 1-LAP was only slightly expressed in normal specimens, while LTBP was not detected. beta 1-LAP was detected in the cytoplasm of neoplastic cells in 9 of 10 patients with ADC. An intense staining was present in stromal cells surrounding the neoplastic glands in all cases except in one carcinoma in situ. LTBP was detected only in stromal cells and in the surrounding extracellular matrix. In IPMN with mild-grade dysplasia and in cystadenoma, beta 1-LAP was strongly expressed in the epithelial cells, while it was poorly detected in invasive IPMN; stromal cells were poorly or not all stained by beta 1-LAP, except in invasive IPMN (n = 2). LTBP was detected in neoplastic cells of three cases with benign IPMN and two of two cases with cystadenoma, while stroma was not immunostained. TGF beta 1 mRNA was strongly expressed in most of the tumors and no difference in expression was observed between the different types of neoplasms. There is no quantitative difference in expression of TGF beta 1 in ADC and in IPMN or cystadenoma. However, the latter are able to secrete TGF beta 1 efficiently, in contrast to ductal ADC as shown by the ability of the neoplastic cells to express both beta 1-LAP and LTBP. Invasive stroma reaction was associated with enhanced beta 1-LAP and LTBP expression in stromal cells and could be mediated by TGF beta 1 via LTBP

Adenocarcinoma, Mucinous↗

Pancreatic duct: morphologic and functional evaluation with dynamic MR pancreatography after secretin stimulation.

PURPOSE: To assess the utility of dynamic MR pancreatography in the evaluation of the behavior of the pancreatic duct after secretin stimulation and to estimate pancreatic exocrine reserve in patients suspected of having acute recurrent or chronic pancreatitis. MATERIALS AND METHODS: Ten healthy volunteers and 13 patients suspected of having pancreatic disease and no obvious markers of chronic pancreatitis were studied. Single-shot turbo spin-echo T2-weighted dynamic MR pancreatograms were obtained before and every 30 seconds during the 10 minutes after secretin administration. Morphologic features and diameter of the pancreatic duct were monitored before and during secretin stimulation. Duodenal filling volume was graded. Results were compared with those of endoscopic retrograde cholangiopancreatography and secretin stimulation testing with collection of pancreatic fluid. RESULTS: Secretin improved the delineation of ductal morphologic features in both groups. Persistent dilatation of the pancreatic duct after stimulation (five patients) was a significant finding (P = .0015) in the diagnosis of papillary stenosis. The mean duodenal filling score was significantly lower in patients with reduced exocrine function (six patients) than that in the volunteers (P < .0001). CONCLUSION: The use of dynamic MR pancreatography with secretin stimulation may be useful for diagnosing pancreatic papillary stenosis or dysfunction and for detecting reduced pancreatic exocrine reserve.

Adult↗