Herein, we report the case of a 72-year-old male patient who presented with a history of left anterior chest wall painless skin lesions. Histology of skin biopsy of the left chest skin lesion showed diffuse dermal infiltration by monomorphic medium-sized blastic cells positive for cluster of differentiation (CD)4, CD45, CD7, CD56, CD43, CD123, T-cell leukemia-1 (TCL1), and B-cell leukemia/lymphoma 2 protein (BCL2). Given the rarity of the disease, standard chemotherapy regimens used in treating different leukemias and lymphomas have been adapted to treat BPDCN. This evidence concerns the gene SPN and leukemia.