Blastic plasmocytoid dendritic cell neoplasm (BPDCN), formerly known as blastic natural killer cell lymphoma CD56+/CD4+ hematodermic neoplasm, is a rare hematologic malignancy derived from the uncontrolled growth of plasmocytoid dendritic cells. Here, CD4 is linked to CD4+/CD56+ hematodermic neoplasm.