Biliary cystadenocarcinoma: report of a case presenting with osseous metastasis and a review of the literature.

Biliary cystadenocarcinoma is a rare malignancy, and osseous metastasis resulting from this tumor have been recorded in only one of the 19 documented cases in the literature. The case report of this 59-year-old male is unusual in that the patient's initial clinical manifestations of the disease were that of osseous metastases, while the primary tumor eluded discovery for greater than 1 year. Although this is the first documented case in which radiation and chemotherapy were used to control the disease, the use of these agents may have contributed to the delay in establishing the primary site of the tumor. The clinical and pathologic features of this and the previously reported cases are reviewed with an emphasis on the newer diagnostic modalities being used in more recent cases to establish the diagnosis for this tumor.