“…2 Among hematologic malignancies, the overall incidence of BPCDN is extraordinarily low (0.4 -0.7%), with two-thirds of all cases affecting elderly persons Ͼ55 years of age, including an increased susceptibility in male subjects (3:1). [3][4][5][6] Frequently an initial finding, skin lesions are almost always (90 -99%) present in BPDCN prompting otherwise asymptomatic patients to seek medical attention and treatment. Evaluation of these patients reveals variable involvement of bone marrow, peripheral blood, spleen, lymph nodes, and extrahematopoietic sites, highlighting the phenotypic heterogeneity of this neoplasm.…”