Incidental cystic lesions of the pancreas found on Endoscopic ultrasound (EUS)

Background: Cystic lesions of the pancreas are increasingly found with the widespread use of cross-sectional imaging studies such as CT and MRI. Incidental cysts are seen in 0.7% of the American population without known pancreatic disease. No prior EUS studies have reported the detection rate of incidental pancreatic cysts. Purpose: Our aim was to find the incidental detection rate of pancreatic cysts on upper EUS exams. Methods: We retrospectively reviewed 785 patients who underwent upper EUS exams for non-pancreatic indications (2/06–7/10). The various indications for the EUS exams included gastric or duodenal lesions (n=222), biliary or liver indications (n=209), periluminal masses and nodes (n=112), abdominal pain (n=109), esophageal masses (n=93), and miscellaneous indications (n=40). The mean age of the patients was 63 (range 17–94), 332M/453 F. Results: Of the 785 patients, incidental pancreatic cysts were found in 21.8% (n=171). Of the 171 patients, 63.95% had a single cyst. The mean largest cyst dimension was 5.5mm (range 1–55mm). Of the 171 patients with pancreatic cysts, 11% (n=18) had follow-up EUS exams (from 1–14 months after the initial EUS exam). In 61% (n=11) of those who had EUS follow-up exams, the cysts were unchanged or smaller. The mean age was 70 for patients with incidental cysts and 61 for those without. Conclusions: Pancreatic cysts were found incidentally in 22% of patients who underwent upper EUS exams for non-pancreatic indications. On EUS follow-up exams, the incidentally found pancreatic cysts were smaller or remained unchanged in 61.1% and were no longer present in 38.9%. Patients with incidentally found pancreatic cysts were significantly older than those without (p<0.01).