Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare but aggressive leukemia. Patients show characteristics similar to leukemia and lymphoma. It is found in the bone marrow and blood but can spread to lymph nodes, the spleen, the central nervous system, and the skin. The skin lesions are characteristic and appear deep purple and numerous. Most patients have been elderly males.
This leukemia derives from plasmacytoid dendritic cells and, like ALAL, has phenotypic ambiguity. It has also been known as blastic NK cell leukemia/lymphoma.
Leukemic cells are negative for many cytochemical stains, such as myeloperoxidase, α-naphthylbutyrate esterase, and ND naphthol AS-D chloroacetate esterase. They show complex karyotypes and genetic mutations.
Treatment requires high levels of chemotherapy. Because this disease is usually found in elderly patients who typically can not tolerate such regimens, targeted therapies are being pursued.
The image to the right is a bone marrow aspirate of BPDCN, which shows medium to large cells with scant cytoplasm, immature chromatin, irregular nuclear contours, and prominent nucleoli.
14. Sullivan, Jill M, and David A Rizzieri. “Treatment of blastic plasmacytoid dendritic cell neoplasm.” Hematology. American Society of Hematology. Education Program vol. 2016,1 (2016): 16-23. doi:10.1182/asheducation-2016.1.16