A rare case of serous cystadenocarcinoma of the pancreas.

Serous cystadenocarcinoma of the pancreas, a rare disease, developed in a 63-year-old Japanese woman. Pathologic examinations of the pancreatic tumor at the subtotal pancreatectomy showed it to be serous cystadenoma with focal atypical lesions. Three years after the operation, however, metastatic liver nodules were found, and the histologic characteristics of these lesions were quite similar to those of the pancreatic neoplasm. Both primary and metastatic tumors were composed of multiple cysts separated by fibrous septa. The epithelium of cysts was cuboidal and had clear cytoplasm, which had positive results for periodic acid-Schiff (PAS) and negative results for PAS with diastase, Alcian blue, and mucicarmine. To the knowledge of the authors, serous cystic neoplasms of the pancreas have been uniformly benign in biologic behavior. Recently, however, serous cystadenocarcinoma of the pancreas has been reported as a new entity. The current case is the second reported case and might support the existence of serous cystadenocarcinoma of the pancreas.