Predictors of Malignancy in Branch Duct Intraductal Papillary Mucinous Neoplasms in the Elderly: Analysis of 234 Patients in a High-Volume Endoscopic Ultrasound Center

Abstract

Purpose: Pancreatic cystic neoplasms are a relatively common finding in clinical practice due to increased abdominal imaging with computed tomography scans. Of particular interest, the approach to managing branch duct intraductal papillary mucinous neoplasms (BD-IPMN) remains unclear. We sought to identify and follow all of the pancreatic cystic lesions, in particular BD-IPMN, to better determine risk factors, management and outcome. Methods: Review of all pancreatic cysts in patients who underwent endoscopic ultrasound (EUS) from 1/5/2007 to 6/26/12 at Roger Williams Medical Center. Patient characteristics, including demographics, cyst locations, pathology, imaging, surgical interventions, and follow-up were analyzed. Results: Two hundred and thirty four patients with pancreatic cystic lesions were identified during a 5.5- year period, with mean age of 65 years and 65% were female. Based on EUS findings, imaging and cystic fluid analysis, 115 (49%) were BD-IPMN, 41 (18%) were serous cystadenoma, 39 (17%) were pseudocyst, 28 (12%) were mucinous cystic neoplasm (MCN), 5 (2%) main duct IPMNs (MD-IPMN) and 6 (2%) uncharacterizable cysts. Ten patients (9%) with BD-IPMN, five patients (80%) with MD-IPMN, and all patients (28) with MCNs underwent surgical intervention. One patient with MD-IPMN did not undergo surgical intervention due to advanced age and multiple co-morbidities. One hundred eight patients with BD-IPMNs are currently being followed clinically and radiographically, while seven patients were lost to follow-up. In the 115 patients with BD-IPMN, 4 patients were <59 years of age, 32 were between 60-69, 34 between 70-79, and 25 were 80-89 years of age. Average cyst size (2.34 cm) was greatest in 70-79 year age group. Seventy-seven patients (67%) were >65 years vs. 38 patients (33%) <65 years, average lesion sizes were 2.05 cm and 1.31 cm respectively. Two patients with BD-IPMN were found to have pancreatic cancer on follow-up and 1 during surgical resection with average age of 80 years. Median follow-up for office visits and surveillance imaging was 12 months. One hundred and five (97%) patients with BD-IPMN are currently cancer free. Average cyst size of patients with and without cancer, are 3.1cm and 1.82cm respectively. Conclusion: BD-IPMNs are the most common pancreatic cystic pathologies identified by EUS, however there is little evidence in the literature to guide the frequency and type of surveillance for BD-IPMN. Within our data set, the data showed that elderly patients (>65 years of age) on average have larger size cysts and higher chance of malignancy. Further prospective studies including multi-center investigations are necessary to better clarify management and surveillance strategy for this unresolved entity.