DNTT and CD4+/CD56+ hematodermic neoplasm: Cutaneous BPDCN was divided into terminal deoxynucleotidyl transferase (TdT) positive and TdT negative subgroups, which did not differ in prognosis, although TdT-positive cases showed a lower median onset age (66 vs 79 years) and higher frequency of extracutaneous lesions.