Prognostic Factors for Early Recurrence After Resection of Pancreatic Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND & AIMS: More than half of pancreatic ductal adenocarcinomas (PDACs) recur within 12 months after curative-intent resection. This systematic review and meta-analysis was conducted to identify all reported prognostic factors for early recurrence in resected PDACs. METHODS: After a systematic literature search, a meta-analysis was conducted using a random effects model. Separate analyses were performed for adjusted vs unadjusted effect estimates as well as reported odds ratios (ORs) and hazard ratios (HRs). Risk of bias was assessed using the Quality in Prognostic Studies tool, and evidence was rated according to Grading of Recommendations Assessment, Development and Evaluation recommendations. RESULTS: After 2903 abstracts were screened, 65 studies were included. Of these, 28 studies (43.1%) defined early recurrence as evidence of recurrence within 6 months, whereas 34 (52.3%) defined it as evidence of recurrence within 12 months after surgery. Other definitions were uncommon. Analysis of unadjusted ORs and HRs revealed 41 and 5 prognostic factors for early recurrence within 6 months, respectively. When exclusively considering adjusted data, we identified 25 and 10 prognostic factors based on OR and HR, respectively. Using a 12-month definition, we identified 38 (OR) and 15 (HR) prognostic factors from unadjusted data and 38 (OR) and 30 (HR) prognostic factors from adjusted data, respectively. On the basis of frequency counts of adjusted data, preoperative carbohydrate antigen 19-9, N status, nondelivery of adjuvant therapy, grading, and tumor size based on imaging were identified as key prognostic factors for early recurrence. CONCLUSIONS: Reported prognostic factors of early recurrence vary considerably. Identified key prognostic factors could aid in the development of a risk stratification framework for early recurrence. However, prospective validation is necessary.

Portal vein resection in pancreatic neuroendocrine neoplasms.

BACKGROUND: Surgery offers the only cure for borderline resectable or locally advanced pancreatic neuroendocrine neoplasms. Data on incidence, perioperative and long-term outcomes of portal vein resection for pancreatic neuroendocrine neoplasms are scarce. This study aimed to analyze the outcome and prognostic factors of portal vein resection in surgery for pancreatic neuroendocrine neoplasms. METHODS: Consecutive patients were analyzed. Portal vein resection was classified according to the International Study Group of Pancreatic Surgery. Clinicopathologic features and overall and disease-free survival were assessed and compared with standard resection in a matched-pair analysis. RESULTS: A total of 54 of 666 (8%) resected pancreatic neuroendocrine neoplasms patients underwent portal vein resection, including 7 (13%) tangential resections with venorrhaphy (type 1), 2 (4%) patch reconstructions (type 2), 35 (65%) end-to-end anastomoses (type 3), and 10 (19%) graft interpositions (type 4); 52% of those underwent pancreatoduodenectomy, 22% distal pancreatectomy, and 26% total pancreatectomy. Postoperative portal vein thrombosis occurred in 19%. Postoperative pancreatic fistula grades B and C (9% vs 16%; P = .357), complications Clavien-Dindo grade ≥IIIb (28% vs 13%; P = .071), and 90-day mortality rate (2% each) were not significantly different compared with 108 matched patients. The 5-year overall survival was 45% (standard resection: 68%; P = .432), and the 5-year disease-free survival was 25% (standard resection: 34%; P = .716). Radical resection was associated with 5-year overall survival of 51% and 5-year disease-specific survival of 75%. CONCLUSION: This is the largest single-center analysis evaluating perioperative and long-term outcomes of portal vein resection for pancreatic neuroendocrine neoplasms. The postoperative complication rate after portal vein resection is comparable with standard resection. The 90-day mortality is low. Radical resection leads to excellent 5-year oncological survival.

Prognostic impact of resection margin status on survival after neoadjuvant treatment for pancreatic cancer: systematic review and meta-analysis.

BACKGROUND: A greater than 1 mm tumour-free resection margin (R0 >1 mm) is a prognostic factor in upfront-resected pancreatic ductal adenocarcinoma. After neoadjuvant treatment (NAT); however, the prognostic impact of resection margin (R) status remains controversial. METHODS: Randomised and non-randomised studies assessing the association of R status and survival in resected pancreatic ductal adenocarcinoma after NAT were sought by systematic searches of MEDLINE, Web of Science and CENTRAL. Hazard ratios (HR) and their corresponding 95% CI were collected to generate log HR using the inverse-variance method. Random-effects meta-analyses were performed and the results presented as weighted HR. Sensitivity and meta-regression analyses were conducted to account for different surgical procedures and varying length of follow-up, respectively. RESULTS: Twenty-two studies with a total of 4929 patients were included. Based on univariable data, R0 greater than 1 mm was significantly associated with prolonged overall survival (OS) (HR 1.76, 95% CI 1.57-1.97; P<0.00001) and disease-free survival (DFS) (HR 1.66, 95% CI 1.39-1.97; P<0.00001). Using adjusted data, R0 greater than 1 mm was significantly associated with prolonged OS (HR 1.65, 95% CI 1.39-1.97; P<0.00001) and DFS (HR 1.76, 95% CI 1.30-2.39; P=0.0003). Results for R1 direct were comparable in the entire cohort; however, no prognostic impact was detected in sensitivity analysis including only partial pancreatoduodenectomies. CONCLUSION: After NAT, a tumour-free margin greater than 1 mm is independently associated with improved OS as well as DFS in patients undergoing surgical resection for pancreatic cancer.

A systematic review and meta-analysis of morbidity and pancreatic fistula after distal pancreatectomy with versus without prophylactic intra-abdominal drainage.

BACKGROUND: The omission of a prophylactic intra-abdominal drainage has been under debate in pancreatic surgery due to the high risk of complications and especially of postoperative pancreatic fistula (POPF). Recently, the second randomized controlled trial (RCT) and two propensity score-matched comparative studies assessing risks and benefits of a no-drainage policy versus prophylactic drainage after distal pancreatectomy (DP) have been published. This systematic review with meta-analysis provides an updated summary of the available evidence on this topic. METHODS: RCTs and non-randomized comparative studies (NCS) investigating outcomes of no drainage versus drainage after DP were searched systematically in MEDLINE, Embase and CENTRAL. Random effects meta-analyses were performed, and the results presented as weighted odds ratios (OR) or mean differences (MD) with their corresponding 95% confidence intervals (c.i.). Subgroup analyses were performed to account for inter-study heterogeneity between RCTs and NCS. RESULTS: Two RCTs and six NCS with a total of 3,610 patients undergoing DP were included of whom 1,038 (28.8%) patients did not receive prophylactic drainage. A no-drainage policy was associated with significantly lower risks of POPF (OR 0.38, 95% c.i. 0.25-0.56; P<0.00001), reduced major morbidity (OR 0.64, 95% c.i. 0.47-0.89; P=0.008), less reinterventions (OR 0.70, 95% c.i. 0.52-0.95; P=0.02) and fewer readmissions (OR 0.69, 95% c.i. 0.54-0.88; P=0.003) as well as shorter length of hospital stay (MD -1.74, 95% c.i. -2.70- -0.78; P=0.0004). Subgroup analyses including only RCTs confirmed benefits of the no-drainage policy. CONCLUSION: A no-drainage policy is associated with reduced POPF and morbidity and can therefore be recommended as standard procedure in patients undergoing DP.

Impact of circumferential resection margin on survival in ampullary cancer: retrospective analysis.

BACKGROUND: Ampullary carcinoma is a clinically variable entity. This study aimed to evaluate prognostic factors for the outcome of resected ampullary carcinoma patients with particular intent to analyse the influence of surgical radicality. METHODS: Patients undergoing resection between 2002 and 2017 were analysed. Clinicopathological parameters, perioperative outcome and survival were examined. Risk factor analysis for postresection survival was performed. Resection margin status was evaluated according to the revised classification for pancreatic adenocarcinoma. RESULTS: A total of 234 patients were identified, 97.9 per cent (n = 229) underwent formal resection, while 2.1 per cent (n = 5) underwent ampullary resection. Histological subtypes were 46.6 per cent (n = 109) pancreatobiliary, 34.2 per cent (n = 80) intestinal, 11.5 per cent (n = 27) mixed, and 7.7 per cent (n = 18) undetermined. In the pancreatobiliary group, tumours were more advanced with more vascular resections, pT4 stage, G3 differentiation and pN+ status. Five-year overall survival was significantly different for pancreatobiliary compared to intestinal (51.7 per cent versus 72.8 per cent, P = 0.0087). In univariable analysis, age, pT4 stage, pN+, pancreatobiliary subtype and positive resection margin were significantly associated with worse overall survival. Long-term outcome was significantly better after true R0 resection (circumferential resection margin-, tumour clearance >1 mm) compared with circumferential resection margin+ (<1 mm) and R1 resections (5-year overall survival: 69.6 per cent, median overall survival 191 months versus 42.4 per cent and 53 months; P = 0.0017). CONCLUSION: Postresection survival of ampullary carcinoma patients is determined by histological subtype and surgical radicality. Intestinal differentiation is associated with less advanced tumour stages and better differentiation, which is reflected in a significantly better overall survival compared to pancreatobiliary differentiation. Despite this, true R0-resection is a prognostic key determinant in both entities, achieving 5-year survival in two-thirds of patients.