Pancreatic masses: A multi-institutional study of 364 fine-needle aspiration biopsies with histopathologic correlation

Only 15% of primary malignant tumors are confined to the gland at the time of presentation. Fine-needle aspiration (FNA) is valuable in confirming the malignant nature of these unresectable lesions. Benign pancreatic lesions and metastatic neoplasms can also be evaluated by fine-needle aspiration. We undertook a retrospective study to evaluate the efficacy of FNA in assessing pancreatic masses. Three hundred and sixty-four radiologically guided FNAs of the pancreas performed between 1986–1996 were reviewed. Surgical material was also evaluated when available and compared to the FNA material. There were 223 men and 141 women. Their ages ranged from 23–90, with a mean of 64 yr. Two hundred and twelve patients (58%) had primary malignant tumors, 183 had adenocarcinomas, 15 had mucinous cystadenocarcinomas, 12 had neuroendocrine tumors, and 2 had pleomorphic giant-cell carcinomas. Ninety-one (43%) had available surgical material which showed adenocarcinoma. Ninety-one patients (25%) had benign aspirates, including 53 showing benign ductal epithelium, 23 showing pancreatitis/inflammation, 10 showing pseudocysts, and 7 showing serous cystadenomas. Surgical material was available in 24 (26%) of these patients. Two of these showed adenocarcinoma. Sixteen aspirates (4%) were suspicious for malignancy, 13 (81%) of which showed adenocarcinoma on follow-up biopsies. Twenty-two aspirates (6%) showed metastatic neoplasms. Twenty-three (6%) had unsatisfactory specimens. Ten (43%) of these had follow-up biopsies, 3 of which were malignant. FNA of primary benign and malignant pancreatic masses is highly sensitive (98%) and specific (100%). Eighty-one percent of the suspicious lesions showed adenocarcinoma on follow-up biopsy. FNA of metastatic neoplasms to the pancreas is also very accurate. This technique can be useful in avoiding unnecessary surgery. Diagn. Cytopathol. 1998;19:423–427. © 1998 Wiley-Liss, Inc.