Other PK-related neoplasms in the differential diagnoses are the plaque-like stage of dermatofibrosarcoma protuberans (DFSP) and the ALK-rearranged CD34-positive spindle cell neoplasm/medallion-like dendrocyte hamartoma/plaque-like CD34-positive dermal fibroma. The gene discussed is ALK; the disease is spindle cell neoplasm.