Mucinous cystic neoplasm of the pancreas with latent malignancy.

Mucinous cystic neoplasms of the pancreas are rare. They have traditionally been classified as cystadenoma or cystadenocarcinoma. Over a 5-year period, and three operations, a patient initially diagnosed as having a cystadenoma of the pancreas was subsequently found at the time of definitive total pancreatectomy to have a cystadenocarcinoma. The recent literature suggests that there is not distinction between cystadenoma and cystadenocarcinoma, since these tumors have been shown to contain coexisting areas of malignant and benign epithelium in both types. The authors' experience with this patient demonstrates the necessity for thorough histologic sectioning of these tumors to document the presence of carcinoma, since all of these tumors should be regarded as potentially malignant neoplasms. Surgical therapy for these lesions should be total excision whenever feasible.