Pancreatic Incidentalomas on CT Colonography: Ignore, Follow up or Investigate?

Background: Increasing use of cross-sectional abdominal imaging such as CT colonography (CTC), has resulted in increased identification of incidental pancreatic cystic lesions. Such incidental findings are a cause for anxiety amongst patients and clinicians and can result in increased cost to healthcare delivery resultant from referral to subsequent investigations. Our study explored the prevalence of incidental cystic pancreatic lesions on CTC at a tertiary pancreatic centre, and their management. Methods: A detailed review of CTC reports and patient case notes between 2010-2016 was undertaken. Patients from both screening (National Bowel Cancer Screening) and non-screening cohorts were included in our study. Results: 136 of 4666 patients who underwent CTC had an incidental finding of a pancreatic lesion (2.9%) and 117 confirmed cystic pancreatic lesions (2.5%). Radiological diagnosis of intraductal papillary mucinous neoplasm (IPMN) was available in the CTC report for 71 patients. Twelve patients (0.2%) were found to have pancreatic ductal adenocarcinoma (PDAC) incidentally at CTC, 2 resectable and 10 unresectable with the diagnosis confirmed on biopsy. Follow-up surveillance imaging recommendations were made for 39.3% of patients within one year of the diagnosis of a cystic pancreatic lesion on CTC. One patient with pancreatic duct dilatation of 7mm was lost in follow-up and was found to develop PDAC at 21 months. Conclusions: Pancreatic lesions are increasingly found incidentally on CTC. All patients with pancreatic cystic tumour should be referred to pancreatic multidisciplinary team for discussion to determine management pathway.