A combination treatment approach and cord blood stem cell transplant for blastic plasmacytoid dendritic cell neoplasm

Abstract

We read with great interest the article on blastic plasmacytoid dendritic cell neoplasm by Pagano et al. The authors propose a strategy of combining ALL like and AML like protocols in this rare and aggressive disease. The authors also emphasize the importance of consolidating when possible with an allogeneic stem cell transplant, in light of the poor prognosis (median overall survival of 8.7 months) of blastic plasmacytoid dendritic cell neoplasm (BPDCN). We would like to share here our experience of successfully treating a patient with cord blood stem cell transplantation using a myeloablative conditioning regimen. Our patient is a 39 year old female who presented with history of easy bruising and shortness of breath. No skin lesions, splenomegaly or lymphadenopathy was found on examination. Peripheral blood counts showed pancytopenia. A subsequent bone marrow aspirate and biopsy confirmed the diagnosis of blastic plasmacytoid dendritic cell neoplasm. She was initially treated with a regimen for aggressive T/NK cell malignancies called SMILE. Day 21 bone marrow after first cycle demonstrated a partial response (PR). She was subsequently treated with an AML regimen consisting of high dose cytarabine and mitoxantrone. She achieved a complete remission (CR) and was consolidated soon after with a cord blood stem cell transplant due to the absence of matched related or unrelated donors. She is doing well, currently about 8 months after stem cell transplant and over 10 months since diagnosis. A sequential combination approach alternating ALL and AML like regimens until CR followed by consolidation with a stem cell transplant when possible is an effective treatment strategy and warrants consideration in patients with this rare and unfavorable prognostic disease. Cord blood stem cell transplant in the absence of a matched related or unrelated donor is feasible and should be attempted in patients who are candidates for transplant.