Blastic Plasmacytoid Dendritic Cell Neoplasm: Single-Center Experience with Two Cases in One Year

Abstract

Background: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare, highly aggressive hematopoietic malignancy that is characterized by cutaneous infiltration with or without bone marrow involvement and further leukemic spread. Its overall incidence is very low, accounting for 0.44% of all hematologic malignancies. The leukemic form of the disease is an extremely rare situation, representing <1% of all cases of acute leukemia. BPDCN predominantly affects males, with a sex ratio of 3:1, and generally occurs in the elderly. Aims: The aim of this presentation was to evaluate symptoms, signs and outcome of two cases of BPDCN. Methods: Between February 2012 and January 2013, we identified 2 patients with BPDCN presenting with skin lesions. Data regarding clinical presentation, diagnosis, staging, treatment and outcome was collected. Results: First patient was female, 78 years-old, the other one was male, 75 years-old. At diagnosis both had asymptomatic skin lesions. The female patient presented with a cutaneous lesion on her right shoulder since the last month. Laboratory data disclosed anemia (hemoglobin: 11, 3 g/dl) thrombocytopenia (139×109/L) and morphologically immature atypical cells in the peripheral blood. Bone marrow aspiration showed 5% infiltration of immature blastic cells with the following immunophenotype: CD45(+), CD123(+), CD85k(+), CD33(-), CD14(-), CD16(-), CD19(-), CD5(-), CD10(-), CD20(-)CD56(+)20%, CD4(+), NG2(+). No chromosomal alterations were detected by cytogenetic analysis of the bone marrow. She had axillary, jugular, submandibular, and supraclavicular lymphadenopathy. Cutaneous, lymph node and bone marrow biopsies, all confirmed the diagnosis of BPDCN. She was treated with Cy-VAD (cyclophosphamide, vincristine, adriamycin and dexamethasone). She achieved CR, continued with induction 2 chemotherapy with Vepesid-Aracytin and died 4 months later of multi-organ failure. The male patient had a generalized purplish dermal rash arising from the head to the lower extremities that presented one week before and progressed very rapidly. Laboratory data revealed anemia (hemoglobin: 10, 9 g/dl), thrombocytopenia (100×109/L), WBC: 8.30∗103/μL with 42% of morphologically immature atypical cells. Bone marrow aspiration showed 88% infiltration of immature blastic cells with the following immunophenotype: CD45 (+) low, CD43 (+), CD123 (+), CD56 (+), CD4(+), CD34 (-).Cytogenetic analysis showed deletion of the long arm of chromosome 12 - deletion of ETV6 gene and deletion of the long arm of chromosome 17- deletion of P53 gene. Computed tomography scans did not disclosed any pathologic lymphadenopathy. Histopathology of skin lesions showed infiltration of blastic cells. Immunohistochemical analysis confirmed the presence of cells with the same immunophenotypic features. He started chemotherapy with Zavedos and Aracytin (3+7) and he is now in CR after this induction. Summary / Conclusion: We present two cases of a rare clinical entity with cutaneous and bone marrow infiltration with blastic plasmocytoid dendritic cells. The diagnosis relied on the immunophenotypic features of the malignant cells, particularly with the presence of CD4 (+) and CD 56(+). Several treatment options have been used so far, all with poor results. The ALL-type treatment regimen that seems to result to a better outcome according to a recent publication resulted to a very short survival. Unfortunately neither of them could proceed to bone marrow transplantation, which is a better therapeutic option for younger patients with good performance status.