TWO METASTATIC CASES OF DERMATOFIBROSARCOMA PROTUBERANS

Summary: Dermatofibrosarcoma protuberans (DFSP) typically presents as a slow growing cutaneous mass with red discoloration, known to be low grade with high local recurrence rates and rarely metastasize. Fibrosarcomatous transformation increases the risk of metastasis. We present two cases of DFSP with uncommon metastatic locations. The first patient is a 68-year-old female with DFSP of the lumbosacral soft tissue and eventual metastasis to the pancreas. The second patient is a 31-year-old male with DFSP of the scalp and eventual metastasis to the proximal femur. In both cases, histology revealed spindle cell neoplasms with bland nuclei, no significant pleomorphism or mitotic figures in a storiform arrangement. Molecular testing demonstrated PDGFB rearrangement, confirming metastatic DFSP.