Blastic Plasmacytoid Dendritic Cell Neoplasm, a Very Rare Hematological Malignancy With Initial Cutaneous Involvement: A Case Report.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a very rare and aggressive hematologic malignancy, arising from plasmacytoid dendritic cells (pDCs). BPDCN frequently has, at least initially, exclusively cutaneous presentation. We present a 45-year-old woman with a 3-month history of rapidly evolving violaceous patches, infiltrated plaques, and bruise-like tumefactions, disseminated on her face and upper trunk. Histopathology of a lesion, along with Flow cytometry of peripheral blood and cerebrospinal fluid, confirmed the diagnosis of BPDCN. The patient received a hyper-CVAD (cyclophosphamide, vincristine, doxorubicin, dexamethasone) regimen and six triple intrathecal chemotherapies. Unfortunately, the patient contracted COVID-19 and died of severe respiratory complications, despite all the available treatment modalities. Our patient presented with typical clinicopathological manifestations of the disease, misdiagnosed for 3 months. The case additionally reflects difficulties in patient management during the COVID-19 pandemic. Dermatologists should be aware of this rare disease, since the early diagnosis and treatment with new emerging drugs may lead to a better prognosis.