Ryohei Kobayashi, Seiko Hirono, Manabu Kawai, Ken-ichi Okada, Motoki Miyazawa, Yuji Kitahata, Masaki Ueno, Shinya Hayami, Norihiko Suzaki, Hiroki Yamaue
Background: This study aimed to evaluate the postoperative recurrence risk factors for intraductal papillary mucinous neoplasm (IPMN), and to suppose an appropriate surveillance after surgical resection.
Methods: This study included 257 consecutive IPMN patients undergoing surgery from 1999 to 2014. Pathological diagnosis showed low- or intermediate-grade dysplasia in 85 patients (33.1%), high-grade dysplasia in 87 patients (33.8%), and invasive intraductal papillary mucinous carcinoma (IPMC) in 85 patients (33.1%). The median postoperative follow-up period was 53.5 months.
Results: Fifty-six IPMN patients (21.8%) had recurrence after surgery, including those with remnant pancreatic recurrence (n=14) and extra-pancreatic recurrence (n=42). Remnant pancreatic recurrence had no influence on the overall survival (OS), whereas, patients with extra-pancreatic recurrence had significantly worse OS (P<0.001). Five patients (35.7%) experienced remnant pancreatic recurrence more than 5 years after surgery. All extra-pancreatic recurrences occurred within 5 years. The OS after recurrence in the remnant pancreas tended to be better among patients who underwent second resection than for those without (P=0.081). We found that the positive pancreatic transection margin was the only independent risk factor for remnant pancreatic recurrence (P<0.001; OR, 8.92), whereas the risk factors for extra-pancreatic recurrence were invasive IPMC (P<0.001; OR, 29.41), mixed-type (P=0.008; OR, 6.41), elevated serum CA19-9 (P=0.019; OR, 3.57), and intraoperative transfusion (P=0.025; OR, 3.33).
Conclusions: Our data suggest that continuous surveillance for more than 5 years after surgery is needed for all IPMN patients to evaluate the remnant pancreatic recurrence, and strict 5-year surveillance is necessary for IPMN patients at risk for extra-pancreatic recurrence.
