Stefano Andrianello

Background: Despite the low malignant potential of pancreatic mucinous cystic neoplasms (MCNs), surgery is still performed. The aim of this pragmatic study was to assess the outcome of surgery and surveillance for patients presenting with a presumed MCN at the first evaluation. Methods: Data for patients with a presumed MCN observed from 2000 to 2016 at the Verona Pancreas Institute and San Raffaele Hospital were extracted from prospective databases. The endpoints were risk of malignancy at pathology and rate of misdiagnosis for the surgical series, expressed as an odds ratio (OR) with 95 per cent confidence interval, and disease-specific survival (DSS) for the surveillance cohort investigated by the Kaplan–Meier method. Results: A total of 424 patients were identified. In the surgical series (229 patients), the rate of misdiagnosis was 19.2 per cent. The rate of malignant MCNs was 10.9 per cent (25 patients). The overall rate of malignancy, including misdiagnoses, was 11.3 per cent (26 patients). Predictors of malignancy were mural nodules (OR 27.75, 95 per cent c.i. 4.44–173.61; P < 0.001), size at least 50 mm (OR 13.39, 2.01 to 89.47; P = 0.007), and carbohydrate antigen 19.9 level (OR 3.98, 1.19 to 13.30; P = 0.025). In the absence of mural nodules and enhancing walls, none of the resected presumed MCNs smaller than 50 mm were malignant. Only patients with high-risk stigmata undergoing surgery experienced a significantly reduced 5-year DSS compared with all other patients (88 versus 100 per cent; P = 0.031). Conclusion: Presumed MCNs with mural nodules, enhancing walls or cysts of 50 mm or larger should be considered for upfront surgical resection owing to the high risk of malignancy. In the absence of these features, the incidence of malignancy is negligible, favouring surveillance in selected patients given the low risk of malignancy and the high rate of misdiagnosis.

Pancreatoduodenectomy (PD) associated with colonic resections (CR) (PD-CR) might be a viable option in case of locally advanced periampullary tumors or right colon cancer. The aim of this review was to reappraise the indications and outcomes of PD-CR focusing on the occurrence of postoperative pancreatic fistula (POPF) and colonic anastomotic leak (CAL). A systematic literature search was performed in Medline and Cochrane Central Register of Controlled Trials (CENTRAL) for studies published between 2000 and 2020 concerning PD-CR for periampullary or colonic neoplasms. Twenty-seven studies were selected. Morbidity after PD-CR ranged from 12 to 65% and surgery-related mortality was approximately 10%. When reported, the rates of POPF and AL were as high as 40% and 33%, respectively. The oncological results were strictly linked to the nature of the primary tumor and did not significantly differ from those achieved with standard resections. Surgical radicality and nodal status resulted the main determinants of outcome for pancreatic and colonic cancer, respectively. Solid evidence about the surgical outcomes of PD-CR is lacking, mainly due to the small proportion of patients undergoing such combined resection. Given the elevated surgical risk, a multidisciplinary evaluation is recommended for patient’s selection. The increasing use of neoadjuvant therapies is expected to further change the indications and outcomes of PD-CR in the next future.

Introduction: Postoperative pancreatic fistula (POPF) is common after distal pancreatectomy (DP). Whilst extensive investigation into potential predictors has been carried out, there is little evidence regarding POPF healing time.Methods: This is a retrospective analysis of all consecutive DPs performed at the Department of General and Pancreatic Surgery, University of Verona Hospital Trust, from 2015 to 2019. Perioperative variables were analyzed identifying possible predictors of POPF healing time defined as days between surgery and last drain removal due to POPF.Results: A total of 496 patients were included. POPF rate was 28.2% and median POPF healing time was 30 days (95% CI 28‐31). Independent predictors of POPF were body mass index (BMI) (OR 1.073, 95% CI 1.010‐1.147, p = 0.040), operative time (OR 95% CI 1.002–1.009, P = .003), and postoperative acute pancreatitis (OR 3.793, 95% CI, 1.852–7.767, P < .001). Independent predictors of POPF healing time were female sex (HR 1.323, 95% CI 1.093–1.998, P = .042), preoperative pancreatic enzyme replacement therapy (HR 2.319, 95% CI 1.195–4.498, P = .013), ASA score 3 (HR 0.278, 95% CI 0.119–0.646, P = .003), pancreatic transection with ultrasonic dissector (HR 0.605, 95% CI 0.404–0.907, P = .015), and positive drain cultures (HR 0.635, 95% CI 0.443–0.910, P = .013).Conclusion: POPF healing after DP is a slow process since only half of patients recover within 30 days of surgery. A longer healing time can be predicted early in the postoperative period with significant implications in therapeutic choices.

The intraductal oncocytic papillary neoplasm (IOPN) of the pancreas has been recognized by WHO classification as a unique intraductal papillary mucinous neoplasm (IPMN) category. IOPN is composed of oxyphil cells, usually expressing MUC5AC, MUC6, and Hep Par-1, and harboring PRKACA/B fusion genes as their genetic hallmark. Although IOPNs are associated with an infiltrative adenocarcinoma in up to 30% of cases, the survival rate after surgical resection approaches 100%. This highlights the importance of the correct IOPN diagnosis, above all in cases with an associated invasive component. In this study, the immunohistochemical expression of CD117 was investigated in 111 IPMNs, including 17 oncocytic, 45 gastric, 20 pancreatico-biliary, and 29 intestinal IPMNs. We also tested the expression of MUC5AC, MUC6, and Hep Par-1 in the IOPN cohort. CD117 positivity was significantly more frequent in IOPNs compared to the other IPMN subtypes (p < 0.0001). Furthermore, within IOPN, a lower or absent CD117, MUC5AC, MUC6, and Hep Par-1 expression tended to be associated with the presence of an infiltrative component. Our findings shed light into the biology of these complex lesions, which are confirmed to be a distinctive IPMN subtype; notably, CD117 emerged as a potential, additional tool in the differential diagnosis of IPMNs.