Pancreatic resections for benign intraductal papillary mucinous neoplasms: Collateral damages from friendly fire.

BACKGROUND: Surgical resection of intraductal papillary mucinous neoplasms is based on preoperative high-risk stigmata/worrisome features, but the risk of overtreatment remains high. The aim of this study was to evaluate surgical indications and perioperative and long-term complications in patients with low-grade intraductal papillary mucinous neoplasms. METHODS: Patients who underwent surgical resection between 2009 and 2018 with a final histology of low-grade intraductal papillary mucinous neoplasms were included. Surgical indications, type of surgery, and short- and long-term outcomes were evaluated. RESULTS: A significant decrease in the rate of patients resected for low-grade intraductal papillary mucinous neoplasms was observed (43.6% in 2009-2012 vs 27.8% in 2013-2018; P = .003), and 133 patients were finally included (62 women, median age: 68 years). Of these, 24.1% had 1 worrisome feature, 39.8% had ≥2 worrisome features, 18.8% had ≥1 high-risk stigmata, and 15.8% had ≥1 worrisome features + 1 high-risk stigmata. Overall surgical morbidity was 55.6%, 15.8% had Clavien-Dindo ≥3 complications, reoperation rate was 3.8%, and 90-day postoperative mortality was 1.5%. After a median follow-up of 60 months, 13 patients (11.5%) had a recurrence of benign intraductal papillary mucinous neoplasm in the pancreatic remnant, and 2 patients (1.8%) developed pancreatic ductal adenocarcinoma. After partial pancreatectomy, 51.3% of patients were taking pancreatic enzyme replacement therapy. Among nondiabetics, 26% developed diabetes after partial pancreatectomy, of which 38% were insulin-dependent. Eighteen patients (13.7%) developed incisional hernia. CONCLUSION: Given the rates of morbidity and long-term complications after pancreatic resections, surgeons should attentively balance the true risks of intraductal papillary mucinous neoplasm degeneration with the risks of surgical resection in each patient.

Main Duct Thresholds for Malignancy Are Different in Intraductal Papillary Mucinous Neoplasms of the Pancreatic Head and Body-Tail.

BACKGROUND & AIMS: The risk of malignancy is uncertain for intraductal papillary mucinous neoplasms (IPMNs) with main pancreatic duct (MPD) of 5-9 mm. No study has correlated MPD size and malignancy considering the anatomic site of the gland (head versus body-tail). Our aim was to analyze the significance of MPD in pancreatic head/body-tail as a predictor of malignancy in main-duct/mixed IPMNs. METHODS: Retrospective analysis of resected patients between 2009-2018 was performed. Malignancy was defined as high-grade dysplasia and invasive carcinoma. MPD diameter was measured with magnetic resonance imaging. Receiver operating characteristic curve (ROC) analysis was utilized to identify optimal MPD cut-off for malignancy. Independent predictors of malignancy were searched. RESULTS: Malignancy was detected in 74% of 312 identified patients. 213 patients (68.3%) had IPMNs of the pancreatic head and 99 (31.7%) of the body-tail. ROC analysis identified 9 and 7 mm as the optimal MPD cut-offs for malignancy in IPMNs of head and body-tail of the pancreas, respectively. Multivariate analysis confirmed that MPD ≥9 mm (pancreatic head) and ≥7 mm (body-tail) were independent predictors of malignancy along with macroscopic solid components, positive cytology and elevated CA 19-9. The risk of malignancy was low for IPMNs with MPD ≤8 mm (pancreatic head) or ≤6 mm (pancreatic body-tail) unless high-risk stigmata or multiple worrisome features were present. CONCLUSIONS: Different thresholds of MPD dilation are associated with malignancy in IPMNs of the head and body-tail of the pancreas. The risk of malignancy for IPMNs with MPD ≤8 mm (pancreatic head) or ≤6 mm (pancreatic body-tail) lacking high-risk stigmata or multiple worrisome features is low.