Composite DermatofibrosarcomaProtuberans-Giant Cell FibroblastomaRecurring as Bednář Tumor-Giant CellFibroblastoma with Mucoid Lakes and WithAmputation Neuroma

Overview

We report an unusual case of composite giant cell fibroblastoma-dermatofibrosarcoma protuberans(DFSP) that, in its second recurrence, contained a pattern of Bednář tumor (BT) and giantcell fibroblastoma (GCF). The recurrent tumor showed extreme myxoid change with creation ofmucoid lakes, which mimicked a pattern of myxoid liposarcoma. One area in the recurrent lesioncontained amputation neuroma overgrown with neoplastic spindle cells, which simulated a nervesheath neoplasm. This case demonstrates common histogenesis of GCF, DFSP and BT, and itshows how broad morphological spectrum can be produced by a composite tumor, especiallywhen the tumor includes unconventional growth pattern or additional non-neoplastic lesion.

Key words:
dermatofibrosarcoma protuberans - giant cell fibroblastoma - Bednar tumor - myxoidliposarcoma - soft tissue