KMT2A (MLL) rearrangements are observed in various types of pediatric and adult leukemia, but only one adult case report has so far shown KMT2A (MLL)-MLLT1 gene rearrangements in blastic plasmacytoid dendritic cell neoplasm (BPDCN) [33]. Here, KMT2A is linked to CD4+/CD56+ hematodermic neoplasm.