Medallion-Like Dermal Dendrocyte Hamartoma: Another CD34⁺ Spindle-Cell Tumor

Medallion-like dermal dendrocyte hamartoma (DH) is a recently described CD34-positive spindle-cell tumor that most frequently affects young girls. Because the lesions are usually detected at or immediately after birth, they have been classified as hamartomas. Dermatofibrosarcoma protuberans (DFSP), superficial or plaque type, shares CD34 positivity. These authors explored the range of clinical-pathologic presentations and genetic findings of DH, with an emphasis on its differentiation from superficial DFSP. They reviewed samples from five DHs and seven superficial DFSPs and employed reverse transcription polymerase chain reaction (RT-PCR) and fluorescence in situ hybridization (FISH) to look for a COL1A1-PDGFB gene rearrangement.

DH occurred…