Skin lesions serve as clues to relapse of pediatric blastic plasmacytoid dendritic cell neoplasm.

A 10-year-old girl with a history of blastic plasmacytoid dendritic cell neoplasm, a rare malignancy in children, presented with recurrent skin eruptions beginning while on maintenance chemotherapy, including mildly pruritic skin-colored plaques, tender indurated nodules, and violaceous bound-down plaques. This case highlights an unusual presentation of relapsed blastic plasmacytoid dendritic cell neoplasm on chemotherapy, with skin lesions providing important clues to the progression of systemic disease.