Minimally invasive versus open central pancreatectomy: A systematic review and meta-analysis.

To compare the procedural outcomes of minimally invasive and open central pancreatectomy. A systematic review in compliance with PRISMA statement standards was conducted to identify and analyze studies comparing the procedural outcomes of minimally invasive (laparoscopic or robotic) central pancreatectomy with the open approach. Random effects modeling using intention to treat data, and individual patient as unit of analysis, was used for analyses. Seven comparative studies including 289 patients were included. The two groups were comparable in terms of baseline characteristics. The minimally invasive approach was associated with less intraoperative blood loss (mean difference [MD]: -153.13 mL, p = 0.0004); however, this did not translate into less need for blood transfusion (odds ratio [OR]: 0.30, p = 0.06). The minimally invasive approach resulted in less grade B-C postoperative pancreatic fistula (OR: 0.54, p = 0.03); this did not remain consistent through sensitivity analyses. There was no difference between the two approaches in operative time (MD: 60.17 minutes, p = 0.31), Clavien-Dindo ≥ 3 complications (OR: 1.11, p = 0.78), postoperative mortality (risk difference: -0.00, p = 0.81), and length of stay in hospital (MD: -3.77 days, p = 0.08). Minimally invasive central pancreatectomy may be as safe as the open approach; however, whether it confers advantage over the open approach remains the subject of debate. Type 2 error is a possibility, hence adequately powered studies are required for definite conclusions; future studies may use our data for power analysis.

PIGA Mutations and Glycosylphosphatidylinositol Anchor Dysregulation in Polyposis-Associated Duodenal Tumorigenesis.

The pathogenesis of duodenal tumors in the inherited tumor syndromes familial adenomatous polyposis (FAP) and MUTYH-associated polyposis (MAP) is poorly understood. This study aimed to identify genes that are significantly mutated in these tumors and to explore the effects of these mutations. Whole exome and whole transcriptome sequencing identified recurrent somatic coding variants of phosphatidylinositol N-acetylglucosaminyltransferase subunit A (PIGA) in 19/70 (27%) FAP and MAP duodenal adenomas, and further confirmed the established driver roles for APC and KRAS. PIGA catalyzes the first step in glycosylphosphatidylinositol (GPI) anchor biosynthesis. Flow cytometry of PIGA-mutant adenoma-derived and CRISPR-edited duodenal organoids confirmed loss of GPI anchors in duodenal epithelial cells and transcriptional profiling of duodenal adenomas revealed transcriptional signatures associated with loss of PIGA. IMPLICATIONS: PIGA somatic mutation in duodenal tumors from patients with FAP and MAP and loss of membrane GPI-anchors may present new opportunities for understanding and intervention in duodenal tumorigenesis.

Patterns, timing and predictors of recurrence following pancreaticoduodenectomy for distal cholangiocarcinoma: An international multicentre retrospective cohort study.

INTRODUCTION: Patients undergoing pancreaticoduodenectomy for distal cholangiocarcinoma (dCCA) often develop cancer recurrence. Establishing timing, patterns and risk factors for recurrence may help inform surveillance protocol strategies or select patients who could benefit from additional systemic or locoregional therapies. This multicentre retrospective cohort study aimed to determine timing, patterns, and predictive factors of recurrence following pancreaticoduodenectomy for dCCA. MATERIALS AND METHODS: Patients who underwent pancreaticoduodenectomy for dCCA between June 2012 and May 2015 with five years of follow-up were included. The primary outcome was recurrence pattern (none, local-only, distant-only or mixed local/distant). Data were collected on comorbidities, investigations, operation details, complications, histology, adjuvant and palliative therapies, recurrence-free and overall survival. Univariable tests and regression analyses investigated factors associated with recurrence. RESULTS: In the cohort of 198 patients, 129 (65%) developed recurrence: 30 (15%) developed local-only recurrence, 44 (22%) developed distant-only recurrence and 55 (28%) developed mixed pattern recurrence. The most common recurrence sites were local (49%), liver (24%) and lung (11%). 94% of patients who developed recurrence did so within three years of surgery. Predictors of recurrence on univariable analysis were cancer stage, R1 resection, lymph node metastases, perineural invasion, microvascular invasion and lymphatic invasion. Predictors of recurrence on multivariable analysis were female sex, venous resection, advancing histological stage and lymphatic invasion. CONCLUSION: Two thirds of patients have cancer recurrence following pancreaticoduodenectomy for dCCA, and most recur within three years of surgery. The commonest sites of recurrence are the pancreatic bed, liver and lung. Multiple histological features are associated with recurrence.