Long interval radiological surveillance of side branch pancreatic duct-involved intraductal papillary mucinous neoplasm in selected patients

Abstract

Aims: Side branch IPMN (SB-IPMN) of the pancreas has a malignancy rate between 10 to 20%. There remains a question on the interval for radiological surveillance for SB-IPMN. We hypothesized that surveillance at longer intervals on selected patients with SB IPMN might be indicated. Methods: This is a retrospective study of prospectively collected data of 276 patients observed from 2000 to 2010. Only patients with follow-up of more than 12 months were included. After 2007, we opted to screen our patients with longer intervals, initially at 12 months then 24 months using MR if no ‘worrisome features’ were present. Results: Of 276 patients, 261 had complete data for analysis and the patients were aged 78 (40–91) years. 232 patients had sole SB-IPMN and 29 had mixed type IPMN and were excluded. 92% of SB-IPMN’s were incidental (n = 209) with 8% symptomatic (n = 24). Single SB IPMN accounted for 84% (n = 195) of all cases with a maximum diameter of 15.5 (5–60) mm. The median of follow up duration was 46 (32–53) months. Short interval radiological surveillance (3–9 months), after the first scan was performed, was 39% (n = 90), while long interval surveillance (12–36 months) was performed in 61% (n = 142). The rate of pancreatic resection in the short and long interval surveillance groups was 4.4% (n = 4) and 5% (n = ) respectively; P = 0.78. Conclusions: Our data suggests that long interval MR surveillance of SB-IPMN patients may be safe and cost effective.