[Blastic plasmacytoid dendritic cell neoplasm. Report of three cases]

Blastic plasmacytoid dendritic cell neoplasm is a rare hematological malignancy derived from immature plasmacytoid dendritic cells. The tumor cells have an immature blastic appearance, and diagnosis is based on the expression of CD4, CD56 y CD123 in the absence of other lymphoid, natural killer, or myeloid antigens. The majority of affected individuals are older people with a mean age of 66 years. Male to female ratio is approximately 3:1. Common presentation includes cutaneous lesions followed by tumor dissemination. Treatment with conventional chemotherapy is ineffective and allogeneic hematopoietic stem cell transplantation is required to achieve remission. We report three male patients, aged 23, 27 and 51 years with the disease. All had multiple, infiltrated pink plaques and nodules on the skin of their face, neck and thorax, measuring 1 to 12 cm in diameter. All tumors were histologically characterized by a monotonous proliferation of medium size cells with blastic features. Tumor cells were positive for CD123, CD56, CD4 and CD7 in all cases. After a mean of follow-up of 14.6 months, one patient died of the disease, one patient is alive and the disease relapsed after 17 months of remission and one patient is alive with no evidence of the disease.