Undifferentiated Carcinoma of the Pancreas With/Without Osteoclast-Like Giant Cells

Abstract

Undifferentiated carcinoma of the pancreas is a rare malignant epithelial neoplasm with a significant component showing no particular differentiation such as keratinization, glandular structure, or mucin production. Clinical recognition of this neoplasm is important because of its poor prognosis with a mean survival of 5 months. The primary diagnostic challenge for surgical pathologists is to distinguish undifferentiated carcinoma from poorly differentiated epithelial, mesenchymal, germ cell, hematopoietic, and other neoplasms. In addition to the morphological characteristics, immunohistochemical analyses are useful for differential diagnosis. In this article, we present a case of undifferentiated carcinoma of the pancreas, followed by a discussion focused on the differential diagnosis of undifferentiated carcinoma, as well as histomorphologic/cytomorphologic, ultrastructural, and immunophenotypic findings helpful for the diagnosis.