Giant cell fibroblastoma

Abstract

Giant cell fibroblastoma is a rare fibroblastic tumor occurring mainly in young patients. Back of thigh, inguinal region and chest wall are the most common sites of involvement. The tumor is characterized by a locally aggressive behavior with no reported metastatic potential. Microscopically, it is composed of spindle cells with a moderate degree of nuclear pleomorphism that infiltrate deep dermis and subcutis. A distinctive feature of this tumor is the presence of peculiar pseudovascular spaces lined by a discontinuous row of multinucleated cells. Features very similar to dermatofibrosarcoma protuberans can be seen. Immunohistochemically, it shows positive staining for CD34, while being negative for S-100 protein and vascular markers. The molecular changes are overlapping with dermatofibrosarcoma protuberans. A case of giant cell fibroblastoma will be presented illustrating the clinicopathological and molecular features of this tumor.