Diagnosis of cystic pancreatic lesions by cytologic examination and carcinoembryonic antigen and amylase assays of cyst contents.

The contents obtained by fine needle aspiration (FNA) from 41 pancreatic cysts in 32 patients were studied cytologically and assayed for amylase and carcinoembryonic antigen (CEA) levels, which have been shown to discriminate pancreatic pseudocysts from mucinous cystic neoplasms and necrotic cystic carcinomas. The results were correlated with the histopathologic findings following surgery or with a clinical and radiologic follow-up of up to two years. The clinical, radiologic and cytologic characteristics did not discriminate pseudocysts from cystic neoplasms. The amylase content of cysts was high in pseudocysts, cystic carcinomas and mucinous cystic neoplasms. The mean CEA content was highest in cystic carcinomas and mucinous cysts and low in pseudocysts. The cytologic diagnosis of mucinous cystic neoplasms and carcinomas had a sensitivity of 54% and a specificity of 91%. The diagnosis of these lesions based on a CEA level greater than 10 ng/ml had a sensitivity of 100% and a specificity of 81%. The adjunctive use of CEA content analysis enhanced the sensitivity of the cytologic diagnosis of mucinous cystic neoplasms and carcinomas to 100%.