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T Ponchon

Publications and source records attributed to T Ponchon.

At least 55 records · Page 3Linked to original sources
PubMed2000

Detection of Ki-ras gene point mutations in bile specimens for the differential diagnosis of malignant and benign biliary strictures.

BACKGROUND AND AIM: The present study was undertaken to determine if detection of Ki-ras gene point mutations in bile specimens could differentiate between benign and malignant biliary strictures. PATIENTS: Bile specimens were obtained from 117 patients exhibiting a stricture of the main bile duct, the nature of which was assessed by cholangiography, histology, and follow up. METHODS: DNA from frozen bile specimens was extracted, amplified, and tested for codon 12 point mutations of Ki-ras gene using sequence specific oligonucleotide hybridisation and mutant allele specific amplification. RESULTS: DNA amplification was successful in 110/117 bile specimens (94%). Detection of Ki-ras gene mutations in bile specimens was positive in 24.4% (22/90) of patients with malignant strictures, in 31.4% (22/70) when only primary malignant tumours were considered, and in 4% (1/25) of patients with benign strictures. Of the 49 patients with histological specimens obtained before surgery, the sensitivity of histology, Ki-ras mutation analysis, and combined methods was 59.2%, 28.6%, and 73.5% respectively. CONCLUSIONS: Our study showed that Ki-ras mutations may be detected in about one third of bile specimens from patients with primary tumours invading the main bile duct. Detection of such mutations appears to be specific and may help to differentiate between benign and malignant biliary strictures.

Bile↗
PubMed1999

Prospective evaluation of transnasal esophagogastroduodenoscopy: feasibility and study on performance and tolerance.

BACKGROUND: With a pediatric endoscope, esophagogastroduodenoscopy (EGD) can be performed via a nasal route in adults. To evaluate this new procedure, we conducted a randomized comparative study of the feasibility of diagnostic transnasal EGD and assessed the factors influencing its quality and tolerance (endoscope diameter or route). METHODS: Transnasal EGD was attempted in 100 patients to assess its feasibility. For the analysis of quality and tolerance, 150 patients were randomized as follows into 3 groups according to the route of examinations: (1) oral route with 9.8 mm diameter standard videoendoscope; (2) oral route with 6.0 mm diameter pediatric videoendoscope; (3) transnasal route with 6.0 mm diameter pediatric videoendoscope. The operator assessed the quality of examination by standard scores. Patients quantified pain intensity, nausea, and choking sensation. RESULTS: Transnasal EGD was feasible in 82% of patients. The quality of the examination was significantly lower with pediatric endoscope. No difference was noted concerning pain intensity, but nausea and choking sensation were significantly reduced when the nasal route was used. CONCLUSIONS: Transnasal EGD is feasible in the routine practice of diagnostic EGD. The nasal route, and not endoscope diameter (6.0 mm vs 9.8 mm diameter), is the determining factor that explains increased patient tolerance during transnasal EGD. Technical improvements in pediatric videoendoscopes are required.

Adolescent↗
PubMed1998

A randomized trial of endoscopic drainage methods for inoperable malignant strictures of the common bile duct.

BACKGROUND: Although metallic stents remain patent longer than plastic stents, the optimal palliation of inoperable malignant biliary strictures remains controversial because of the high cost of metallic stents and short patient survival. METHODS: A total of 101 patients (mean age 72.5+/-12.9 years) with malignant strictures of the common bile duct were included in this study, after three exclusions for technical failure (n = 3) and one for noncompliance with study design. The etiology of the strictures included pancreatic cancer (65), cholangiocarcinoma (21), ampullary tumor (3), and metastatic lymph nodes (12). Patients were randomized to receive either an 11.5F polyethylene stent to be exchanged in case of dysfunction (group 1, n = 33), an 11.5F stent to be exchanged every 3 months (group 2, n = 34), or a self-expanding metallic Wallstent (group 3, n = 34). RESULTS: Endoscopic procedures were successful (including complete relief of jaundice) in 97.1 % of cases. Procedure-related morbidity was 11.9%, and mortality was 2.9%. Bilirubinemia after 48 hours (37.2%+/-21.7% decrease from the preoperative level) did not differ between groups. Patients were followed for a mean of 166 days (median 143, range 0 to 596 days). Overall survivals were not different between groups, but complication-free survival for groups 2 and 3 was longer than that of group 1 (p < 0.05). Cumulated hospital days were 7.4+/-1.5, 10.6+/-1.7, and 5.5+/-1.4 (groups 1, 2, and 3, respectively) (p < 0.05; analysis of variance). Cost analysis showed that metallic stents were advantageous in patients surviving more than 6 months, whereas a plastic stent was advantageous in patients surviving 6 months or less. CONCLUSIONS: Metallic stents and plastic stents exchanged every 3 months are valuable alternatives for increasing complication-free survival in patients with malignant strictures of the common bile duct. Metal stents are advantageous in patients with the longest life expectancy.

Adult↗
PubMed1998

Predictive factors for survival of patients with inoperable malignant distal biliary strictures: a practical management guideline.

BACKGROUND: Stenting is the treatment of choice for inoperable malignant strictures of the common bile duct. Criteria for the choice of stents (plastic versus metallic) remain controversial because predicting survival is difficult. AIMS: To define prognostic factors in order to improve the cost effectiveness of endoscopic palliation. PATIENTS: One hundred and one patients were included in a prospective trial. Seven prognostic variables for survival were analysed (age, sex, bilirubinaemia, weight loss, presence of liver metastases, and tumour histology and size). All patients were followed until death or at least one year after inclusion. By the end of the study, 81 (80.2%) patients had died. RESULTS: In univariate analysis, the variables associated with survival were weight loss (p < 0.05) and tumour size (p < 0.01). By multivariate analysis, tumour size was the only independent prognostic factor (p < 0.05). A threshold of 30 mm at diagnosis distinguished two survival profiles: the median survival of patients with a tumour greater than 30 mm was 3.2 months, whereas it was 6.6 months for patients with a tumour less than 30 mm (p < 0.001). CONCLUSIONS: A practical strategy could be based on tumour size at diagnosis: a metal stent should be systematically chosen for patients with an inoperable tumour smaller than 30 mm, while larger tumours are efficiently palliated by a plastic stent.

Adult↗
PubMed1997

What role can endoscopy play in the management of biliary complications after laparoscopic cholecystectomy?

BACKGROUND AND STUDY AIMS: This study was carried out to establish the indications for biliary endoscopy due to biliary complications after laparoscopic cholecystectomy (LC). PATIENTS AND METHODS: One hundred nineteen patients (36 men, 86 women; median age 59, range 16-93) were referred for endoscopic retrograde cholangiopancreatography (ERCP) to five centers between 1990 and 1994, and included in the study. The delay between LC and ERCP was 105 +/- 21 days. RESULTS: Four types of complications were observed. a) Fifty-seven patients had residual stones or clip migration into the common bile duct (CBD); all were successfully treated with endoscopic sphincterotomy (ES). b) Twelve major injuries to the CBD were diagnosed by ERCP; successful surgical repair was carried out in most of these cases. c) Twenty patients had a partial biliary stricture; endoscopic stenting was attempted as a primary procedure in eight patients, with a satisfactory outcome in five (63%). d) Thirty patients had a bile leak; endoscopic therapy (26 patients) led to recovery in 18 (69%). The benefit of endoscopic treatment was less clear in five (19%); ES failed to bring about improvement in three patients (12%). CONCLUSIONS: ERCP is indicated when a biliary complication is suspected after laparoscopic cholecystectomy. Endoscopic sphincterotomy is effective for the treatment of retained stones, clip migration, and bile leakage. Endoscopic stenting may be offered as a primary option in partial CBD strictures.

Adolescent↗
PubMed1997

[Value of endoscopy in the treatment of chronic pancreatitis].

Endoscopic treatment in patients with chronic pancreatitis involves several features: sphincterotomy of the wirsung, dilatation, insertion of a prosthesis, cystoenterostomy, cystowirsungostomy. Extracorporal lithotrity is often associated. Endoscopic treatment appears to give satisfactory short-term results in cases with pain, pseudocyst or pancreatic fistula. Morbidity is low. The optimum duration of endoscopic drainage via the prosthesis is still a question of debate and the long-term efficacy remains to be demonstrated. Endoscopic treatment is indicated in patients with a definitive or temporary surgical risk or may be indicated for all symptomatic patients. In this case, endoscopic treatment would be used as a therapeutic test. Stenosis of the main bile duct is not at present a good indication for endoscopic treatment as this stenosis is resistant to balloon dilatation and prosthesis calibration.

Chronic Disease↗
PubMed1996

Methods, indications, and results of percutaneous choledochoscopy. A series of 161 procedures.

OBJECTIVE: Nonsurgical methods for evaluation and treatment of the biliary tree are usually done under fluoroscopic guidance. Direct visualization of the bile ducts, that is, choledochoscopy, could provide a more precise method with which to perform these maneuvers. The methods, indications, and results of percutaneous choledochoscopy are discussed from a series of 161 procedures performed in 123 consecutive patients. METHODS AND RESULTS: Ninety-six patients had transhepatic drains and 27 had T-tubes implanted. Biopsy of bile duct stenosis was conducted in 52 cases. The sensitivity for the diagnosis of malignancy was 78%, and the authors recommended this method in case of nonsurgical treatment of stenosis. Gallstone extraction was performed in 75 cases (35 intrahepatic). Lithotripsy was necessary for 64 patients and complete gallstone clearance was obtained for 69 patients (92%). The rate of stone recurrence was 18.1% (median follow-up, 32 months), prompting the authors to reconsider surgery for the treatment of underlying disease. Laser photocoagulation was used successfully for two of three patients to ablate an intraductal adenoma. In eight cases of cholangiocarcinoma, the laser effect was too short to satisfactorily relieve obstruction of the intrahepatic bile ducts. Morbidity dramatically decreased from 53.7% to 5% when progressive dilation of the tract, aseptic conditions, and general anesthesia were applied systematically. CONCLUSION: Percutaneous choledochoscopy can be used routinely, provided that strict techniques are adhered to. This procedure should be reserved for only a small subset of biliary diseases.

Adolescent↗
PubMed1996

[Pancreatectomy for intraductal papillary mucinous tumor of the pancreas].

Twelve cases of pancreatectomy for intraductal papillary-mucinous tumor of the pancreas operated between August 1985 and February 1996 are reported. Mean age of the patients was 57.6 years (range: 25 to 77 years). Two of them were female and 10 were male. Ten patients underwent a pylorus preserving pancreaticoduodenectomy, one patient a segmental isthmic pancreatectomy and one other a left pancreatectomy. Histologic examination of the operative specimen showed benign ademomatosis with severe dysplasia in 3 cases, intramucosal or microinvasive carcinoma in 7 cases and invasive carcinoma in 2 cases. Two patients died during the period of follow-up, one at 20 months from metastases, the other one at 33 months accidentally. The 10 remaining patients were alive and disease-free with a follow-up of 3 to 93 months (mean time of follow-up: 38 months). Pancreatectomy is indicated without delay as soon as the diagnosis of this uncommon tumor is obtained.

Adenocarcinoma, Mucinous↗
PubMed1995

Value of endobiliary brush cytology and biopsies for the diagnosis of malignant bile duct stenosis: results of a prospective study.

BACKGROUND: Before considering a nonsurgical method of management of a bile duct stenosis, a tissue diagnosis is highly desirable. In a prospective study we have evaluated the feasibility and reliability of endobiliary brush cytology and biopsies performed at the time of endoscopic retrograde cholangiography. METHODS: Two hundred thirty-three consecutive patients underwent an attempt at endobiliary brush cytology and biopsies of bile duct stenosis when no mass was detected on ultrasound and CT scan. RESULTS: The material for cytology was sufficient for analysis in 210 cases (90%) and biopsies were obtained in 128 cases (55%). One hundred fifteen patients had both cytology and biopsies (49%). For the diagnosis of malignant stenosis, the sensitivity was 35% for cytology, 43% for biopsies, and 63% for the combination of cytology and biopsies. For both cytology and biopsies, the specificity was 97%. In the cases of cancer primarily involving the bile ducts, the sensitivity was 86% when combining both cytology and biopsies. CONCLUSIONS: Endobiliary sampling is technically difficult and has a limited sensitivity for the diagnosis of malignant biliary stenosis. Biopsies should be combined with cytology to increase the sensitivity.

Adult↗
PubMed1995

Endoscopic stenting for pain relief in chronic pancreatitis: results of a standardized protocol.

BACKGROUND: Pancreatic endoscopic stenting aims to relieve abdominal pain due to chronic pancreatitis. Optimal treatment modalities and post-treatment effects have still to be determined. The object of this study was to investigate the results of a standardized protocol of endoscopic stenting. METHODS: Twenty-three patients with abdominal pain due to chronic pancreatitis and stricture of the distal main pancreatic duct were treated according to the following protocol: after balloon dilation of the stenosis, a 10F stent was placed into the main pancreatic duct and then exchanged every 2 months, the total duration of drainage being 6 months. RESULTS: Use of analgesics could be discontinued in 17 patients (74%) on termination of drainage, and in 12 patients (52%) 1 year later. These results were significantly associated with reduction of main pancreatic duct diameter and resolution of stricture, but were not influenced by abstinence from alcohol and pancreatic enzyme supplementation. CONCLUSIONS: Pancreatic duct stenting results in short-term clinical improvement in patients with chronic pancreatitis and proximal main pancreatic duct stricture. Persistence of advantageous clinical results is to be expected in 50% of cases and when strictures have resolved.

Abdominal Pain↗
PubMed1995

Biopsies of the ampullary region in patients suspected to have sphincter of Oddi dysfunction.

Tumors of the ampulla of Vater that develop within the ampulla can go unrecognized during endoscopic examination. Patients with intra-ampullary tumors may present with a clinical picture very similar to that of sphincter of Oddi dysfunction. We wished to determine what percentage of patients initially diagnosed with sphincter of Oddi dysfunction are later found to have an intra-ampullary neoplasm. Sixty-nine consecutive patients were considered to have sphincter of Oddi dysfunction and subsequently were treated with endoscopic sphincterotomy. No gallstones were found in the gallbladder or bile duct. Patients returned for biopsies of the ampulla at least 10 days after the endoscopic sphincterotomy. Three patients (4.3%) were found to have ampullary adenocarcinoma. Thirty-six had normal results of biopsy analysis and 30 had inflammatory or fibrotic changes on biopsy specimens. No objective criteria (clinical, biologic, endoscopic, or radiographic) that would help to distinguish between an ampullary tumor and sphincter of Oddi dysfunction were identified. Biopsies of the ampulla should be performed in all patients suspected of having sphincter of Oddi dysfunction and treated by endoscopic sphincterotomy.

Adenocarcinoma↗