The cytology of pancreatic foamy gland adenocarcinoma.

All cell block specimens from pancreatic fine-needle aspirations (FNAs) obtained between January 1, 2002, and June 30, 2003, were reviewed for foamy gland adenocarcinoma (FGA). All smears from these cases were reviewed for cytologic features, including those previously noted in conventional pancreatic adenocarcinoma. Fifty-two cell block specimens showed adenocarcinoma. Of these, 12 (23%) showed histologic features of FGA. This pattern predominated in 6 cases and was present focally in 6 cases. Although there were relatively low nuclear/cytoplasmic (N/C) ratios, other features of adenocarcinoma were present universally, including loss of cohesiveness, nuclear overlap or loss of "honeycomb" architecture, anisonucleosis (> 4 to 1), irregular nuclear contours, prominent nucleoli, and atypical chromatin. Background necrosis was present in 8 cases. Distinct cell borders were present in 9 cases, and foamy cytoplasm was present in all cases. Pancreatic FGA is a recently described histologic pattern of pancreatic adenocarcinoma. It is not uncommon, and we identified the pattern, at least focally, in 23% of our FNA cell blocks. Although cytologic samples show low N/C ratios, most cytologic features of conventional pancreatic adenocarcinoma are present, and the diagnosis presents little additional difficulty.