Undifferentiated (anaplastic) carcinoma with osteoclast-like giant cells of the pancreas: a series of 5 cases with clinicopathologic correlation and cytomorphologic characterization

Initial diagnosis of UCOGCP is frequently made via EUS-FNA of pancreas tumors, with cytomorphologic features on smears and hematoxylin and eosin stained slides prepared from cell block material being characteristic for the diagnosis. Although the cellular constituents have a consistent immunophenotype, the diagnosis can be based on the morphologic features alone. UCOGCP is an important diagnosis as it may have a distinct clinical course from undifferentiated carcinomas of the pancreas lacking osteoclast-like giant cells.