Cytogenetic Findings in a Case of Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN).

Objectives: Blastic plasmacytoid dendritic cell neoplasm (BPDCN), previously known as natural killer (NK) cell leukemia/lymphoma, is categorized by the World Health Organization as a sole entity. Most often, BPDCN presents with features of both lymphoma and leukemia. The average age at diagnosis is 60 to 70 years and there are more men than women who are diagnosed with BPDCN. Herein we report a 67-year-old female with a recent peripheral blood morphology revealing a hematopoietic leukemia process. Flow cytometry revealed an atypical cell population without B-cell or T-cell lineage expression. It was positive for CD45 and CD123 and negative for CD34. The peripheral blood showed blastic plasmacytoid dendritic cell neoplasm, macrocytic anemia and moderate thrombocytopenia. Chromosome analysis showed an abnormal clone with i(7)(q10) and monosomies of chromosomes 13 and 15. She underwent a bone marrow biopsy. Bone marrow and peripheral blood showed a blastic plasmacytoid dendritic cell neoplasm (BPDCN), hypercellular marrow (estimated 95%) with 90.4% blasts (aspirate smear).