EUS and MRI/MRCP Findings in Pancreatic Cancer Screening for Individuals Who Harbor a BRCA2 Deleterious Germline Mutation

Abstract

Introduction: Individuals with BRCA2 gene mutations have up to a 7% lifetime risk for developing pancreatic cancer (PC). In addition, these mutations account for the highest percentage of inherited causes of PC. In 2012 the International Cancer of the Pancreas Screening (CAPS) Consortium developed statements on screening, surveillance and management of patients with increased risk for familial PC. Our aim was to describe longitudinal endoscopic ultrasound (EUS) findings in patients undergoing PC screening who harbor a mutation in BRCA2 and to correlate EUS and MRI/MRCP findings. Methods: Patients with BRCA2 mutations were identified through the University of Michigan Breast and Ovarian Cancer Risk Evaluation Program Registry. Demographic information and descriptive analysis of screening tests were obtained from a prospective cohort. Results: 91 patients with BRCA2 mutations were enrolled in the registry, of which 37 (40.7%) were referred for PC screening discussion. Patients were followed for a mean of 7.5 years (+4). Demographic and clinical characteristics were similar between those who were and were not sent for PC screening (mean age 55.2±12.2y v. 54.5±11.5y; mean BMI 29.3±7.3 v. 25.8±5.5). Patients with a family history of PC (OR 9.5, 95% CI 1.1-82.5) were most likely to be referred for PC screening discussion. Of those referred, 18 (48.6%) BRCA2 mutation carriers pursued PC screening. All had EUS performed with 9 (50%) having both EUS and MRI. An average of 2.52 EUS and 1.75 MRI exams were performed. A normal exam on EUS or MRI was present in 12 (66.7%) and 7 (77.8%) patients, respectively. No solid lesions were identified on any surveillance exam. Two patients (11.1%) had a cystic lesion identified on initial EUS consistent with branch-duct (BD) IPMN. An additional 2 patients (11.1%) developed cystic lesions consistent with BD-IPMN after an average of 5 years. Other EUS findings included diffuse echogenicity suggestive of fatty infiltration of the pancreas in 2 (11.1%) patients and changes indeterminate or suggestive of chronic pancreatitis based on Rosemont criteria in 3 (16.7%) patients. Conclusion: In individuals with BRCA2 mutations, less than ½ pursued PC screening. The majority of patients were found to have normal screening examinations. Overtime, 22.2% of patients had findings consistent with BD-IPMNs. Further studies should be performed to determine appropriate screening recommendations and intervals.