S-564 Blastic plasmacytoid dendritic cell neoplasm: Diagnosis and Therapeutic approaches of Ten cases.

Background:?Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy that typically presents in the form of skin manifestations with or without lymph node and bone marrow involvement. Given its rarity and recent recognition as a distinct pathological entity, no standard of treatment exists for this aggressive disease and its prognosis is particularly dismal.?Methods:?We retrospectively analyzed clinical features and treatment outcomes of patients who were diagnosed with BPDCN between 2000 and 2014.?Results:?Ten patients had a median age at diagnosis of 41 years (range, 18-79), and 7 patients were male. Sites of disease involvement were the skin (n＝7), lymph node (n＝5), bone marrow (n＝2), liver (n＝2), spleen (n＝2), and soft tissue (n＝1). Intensified chemotherapy regimens such as hyperCVAD regimen (cyclophosphamide, vincristine, doxorubicin, dexamethasone, methotrexate, cytarabine), and VPDL (vincristine, methylprednisolone, daunorubicin, L-asparaginase) were used as a first-line treatment. Although all patients treated with intensified chemotherapy showed an objective response (5 patients with complete response) with median progression-free survival of 11.2 months (range 6.2-19.4 months), complete remission was not sustained for more than two years in any case. The response was relatively long-lived compared with previously reported CHOP-like regimens, but the above regimens do not result in long-term remission.?Conclusions:?All patients treated with hyperCVAD or VPDL showed an objective response, but the duration of response was relatively short. Thus, the development of more effective induction as well as consolidation treatment strategy should be warranted to improve this rare disease entity.