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- Frozanpor, Farshad
(author)
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Issues relevant to the endoscopic and surgical management of pancreatic carcinoma
- 2011
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Doctoral thesis (other academic/artistic)abstract
- Background: A substantial proportion of the patients with pancreatic cancer require palliative decompression of the extrahepatic bile duct obstruction by endoscopic stent insertion. Only 20% of patients with pancreatic cancer are suitable for resection, which is considered to be a high-risk procedure with postoperative pancreatic fistula (PF) formation in a central role. The main objectives of this thesis were divided into two parts: i.e. to determine whether a covered self-expandable metal stent (cSEMS) was preferable to a conventional uncovered self-expandable metal stent (uSEMS) for palliation of jaundice in patients with an unresectable distal malignant biliary obstruction (Study I). The second part addressed factors that may affect the PF formation rate after distal pancreatectomy (DP) (Study II) and pancreaticoduodenectomy (PD) (Study IV) and the alleged PF preventive effect of pancreatic duct stenting (Study III) after DP. Method and Patients: I) 400 patients with unresectable distal malignant biliary obstruction were enrolled in a randomized controlled trial to compare a cSEMS with a uSEMS. Outcome measures were time to stent failure, survival time and complication rate. II) In a hypothesis-generating study, 51 consecutive patients undergoing DP were analysed regarding the impact of demographic factors, clinicopathological features and radiological parameters on the risk of developing PF. III) 58 patients were randomized to either intraoperative pancreatic duct stent insertion (DP+stent) or not to elucidate the effect of the stent on the PF rate after DP. IV) 182 consecutive patients undergoing PD were recruited to define predictive radiological variables that affected the risk for PF after PD. Results: I) The median survival time in the palliative patients was short with 116 days and 174 days, respectively, in the covered and uncovered stent group. The first quartile period with a patent stent was 154 days in the cSEMS group and 199 days in those having a uSEMS (p = 0.326). Stent migration occurred in 6 cSEMS patients (3%) and in none of the patients in the uncovered group (p = 0.036). II) Pancreatic fistula was diagnosed in 17 (33%) of the DP patients, and it occurred more frequently after hand suturing of the transection area than after the use of a stapler (69.2% vs 21.1%; OR, 40.4; 95% CI, 3.36–486; p = 0.004). The preoperative radiological estimate of the alleged pancreatic remnant indicated that a large volume of the pancreatic remnant was associated with a higher PF risk (57.1% vs. 20.8%; OR, 6.14; 95% CI, 1.14–39.0; p = 0.035). III) Clinically significant PF occurred in 6 DP patients (22.2%) and in 11 (42.3%) DP+stent (OR, 2.57; 95% CI, 0.78–8.48; p = 0.122). Operating time and hospital stay were significantly longer in the DP+stent group. IV) Clinically significant PFs were diagnosed in 35 of the 182 (19.2%) PD patients. CT and MRI-based measurements of the volume of the pancreatic remnant predicted the subsequent risk of PF (OR, 3.712, 95% CI: 1.582 - 8.710, p=0.003), as did a small duct diameter (OR: 8.459; 95% CI, 3.106–23.04; P ≤ 0.001). The size of the pancreatic remnant and width of the pancreatic duct maintained their impact on leakage risk also in a multivariate analysis. Conclusions: cSEMS and uSEMS are equally effective in palliating patients with malignant extrahepatic biliary obstruction, but with a tendency for the former to migrate. Preoperative radiological analyses and estimates of the remnant gland after resection seem to be a useful instrument to predict PF formation after DP as well as PD. Prophylactic pancreatic stent insertion does not reduce PF after a standardized resection of the body and tail of the pancreas.
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| 2. |
- Kullman, Eric, et al.
(author)
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Covered versus uncovered self-expandable nitinol stents in the palliative treatment of malignant distal biliary obstruction: results from a randomized, multicenter study
- 2010
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In: GASTROINTESTINAL ENDOSCOPY. - : Elsevier Science B. V., Amsterdam. - 0016-5107 .- 1097-6779. ; 72:5, s. 915-923
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Journal article (peer-reviewed)abstract
- Background: Covered biliary metal stents have been developed to prevent tumor ingrowth. Previous comparative studies are limited and often include few patients. Objective: To compare differences in stent patency, patient survival, and complication rates between covered and uncovered nitinol stents in patients with malignant biliary obstruction. Design: Randomized, multicenter trial conducted between January 2006 and October 2008. Setting: Ten sites serving a total catchment area of approximately 2.8 million inhabitants. Patients: A total of 400 patients with unresectable distal malignant biliary obstruction. Interventions: ERCP with insertion of covered or uncovered metal stent. Follow-up conducted monthly for symptoms indicating stent obstruction. Main Outcome Measurements: Time to stent failure, survival time, and complication rate. Results: The patient survival times were 116 days (interquartile range 242 days) and 174 days (interquartile range 284 days) in the covered and uncovered stent groups, respectively (P = .320). The first quartile stent patency time was 154 days in the covered stent group and 199 days in the uncovered stent group (P = .326). There was no difference in the incidence of pancreatitis or cholecystitis between the 2 groups. Stent migration occurred in 6 patients (3%) in the covered group and in no patients in the uncovered group (P = .030). Limitations: Randomization was not blinded. Conclusions: There were no significant differences in stent patency time, patient survival time, or complication rates between covered and uncovered nitinol metal stents in the palliative treatment of malignant distal biliary obstruction. However, covered stents migrated significantly more often compared with uncovered stents, and tumor ingrowth was more frequent in uncovered stents.
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| 3. |
- Olsson, Greger, et al.
(author)
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Preoperative biliary drainage by plastic or self-expandable metal stents in patients with periampullary tumors : results of a randomized clinical study.
- 2017
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In: Endoscopy international open. - : Georg Thieme Verlag KG. - 2364-3722 .- 2196-9736. ; 5:9, s. E798-E808
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Journal article (peer-reviewed)abstract
- BACKGROUND AND STUDY AIMS : Preoperative biliary drainage in patients with periampullary tumors and jaundice has been popularized to improve the quality of life and minimize the risks associated with subsequent radical surgery. The aim of this study was to investigate the possible superiority of self-expandable metal stents (SEMS) over plastic stents, by comparing the amount of bacteria in intraoperatively collected bile and using this variable as a proxy for the efficacy of the respective biliary drainage modalities.PATIENTS AND METHODS : In this randomized clinical trial, 92 patients with obstructive jaundice were enrolled; 45 were allocated to the plastic stent group and 47 to the SEMS group. The primary outcome was the extent and magnitude of biliary bacterial growth at the time of surgical exploration. Secondary outcomes were: macroscopic grading of inflammation of the stented bile ducts, occurrence of adverse events after stenting, stent dysfunction, recognized surgical complexities, and incidence of postoperative complications.RESULTS: = 0.03). Postoperative complications in patients who underwent curative surgery were more common in patients with plastic stents (72 % vs. 52 %), among which clinically significant leakage from the pancreatic anastomoses seemed to predominate (12 % vs. 3.7 %); however, none of these differences in postoperative adverse events reached statistical significance.CONCLUSION: This randomized clinical study was unable to demonstrate any superiority of SEMS in the efficacy of preoperative bile drainage, as assessed by the amount of bacteria in the intraoperatively collected bile. However, some data in favor of SEMS were observed among the clinical secondary outcomes variables (preoperative stent exchange rates) without increases in local inflammatory reactions.
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