Differential diagnosis of cystic neoplasms of the pancreas by fine-needle aspiration.

Fine-needle aspiration biopsy of pancreatic lesions is becoming widespread. Pathologists need to be familiar with the cytologic features of pancreatic tumors, of which cystic neoplasms are a distinct subset. Of our 31 pancreatic aspirates diagnostic of neoplasia, six were diagnosed as cystic by radiographic imaging. These cases were compared. Similar symptoms were experienced by all of these patients, although those with malignant tumors lost the most weight. Loss of border definition, ascites, and liver metastases were the only radiologic clues to malignancy. Each entity had distinguishing cytologic features. These cases illustrate the importance of knowing the clinical, radiologic, and cytologic features of pancreatic cystic neoplasms to arrive at a preoperative diagnosis and determine proper treatment.