Management of suspected pancreatic cystic neoplasms based on cyst size

BackgroundEvaluation and management of cystic pancreatic neoplasms remain problematic. International consensus guidelines have advised resection for lesions greater than 3 cm.MethodsWe reviewed our prospective pancreatic cystic neoplasm database for outcomes based on a cyst size of 3 cm.ResultsFive hundred patients have been managed from 1999 to 2006. There were 349 patients (70%) with cysts less than or equal to 3 cm: 293 (84%) were not operated, including 243 nonmucinous cysts: 2 failed observation (0.8%, mean follow-up of 24 months). Fifty-six patients with cysts less than or equal to 3 cm were initially operated (16%), including 23 asymptomatic patients. Histopathology showed intraductal papillary mucinous neoplasm (IPMN) in 20, mucinous cystic neoplasm (MCN) in 18, and serous cystadenoma in 5. Twelve had carcinoma (21%). A total of 151 patients (30%) had cysts greater than cm: 87 (50%) were not operated, including 68 that were nonmucinous: 2 failed observation (2.9%, mean follow-up of 47 months). Sixty-four patients with cysts greater than 3 cm (42%) were initially operated, and final pathology showed MCN in 27, serous cystadenoma in 11, IPMN in 7, and pseudocyst in 7. Twelve had carcinoma (19%). Patients with cysts less than or equal to 3 cm were less likely to be operated (16 vs 42%; P < .001), less often symptomatic (39 vs 50%; P = .017), while older (mean age, 65 vs 61 years; P = .03). Had patients been managed by size alone, up to 20% would have received inappropriate treatment. Management based on aspiration was significantly better in predicting mucinous neoplasms compared with size (75% vs 57%; P < .001), including asymptomatic patients less than or equal to 3 cm (78% vs 65%; P = .003).ConclusionSize of pancreatic cystic lesions alone is not a reasonable basis for determining management.