Blastic plasmacytoid dendritic cell neoplasm following acquired erythropoietic protoporphyria.

A 56-year-old Texas rancher with a prior diagnosis of acquired erythropoietic protoporphyria secondary to an underlying myelodysplastic disorder developed an uncommon tumor, blastic plasmacytoid dendritic cell neoplasm (BPDCN). During his initial disease, analysis revealed a TET2 mutation, which is the most common mutation associated with BPDCN. This article discusses this unusual hematopoietic neoplasm, the possible evolution from erythropoietic protoporphyria, and the underlying myelodysplastic process.