Blastic plasmacytoid dendritic cell neoplasm
A 76-year-old man was referred for evaluation of various cutaneous lesions. He had a\nprior history of total prostatectomy due to prostate adenocarcinoma 6 years before the\ncurrent observation and myelodys plastic syndrome (MDS) presenting with neutropenia\nfollowed-up in hematology for 4 years. His neutropenia had been extensively studied\nthrough imaging studies and bone marrow aspirate and biopsy. MDS of the refractory\ncytopenia with multilineage dysplasia subtype was diagnosed and an expectant approach\nwith careful observation was undertaken.\nTwo months before referral, he progressively developed multiple violaceous plaques and\nnodules on the face and scalp. He denied any constitutional symptoms and mentioned just\na prior episode of minor head trauma. The physical examination revealed multiple\nwell-demarcated, indurated plaques and nodules scattered throughout the right\nfrontotemporal and biparietal areas as well as a 7 cm wide tumor in the anterior\ninterparietal area ( and ). Several mandibular, cervical and supraclavicular\nlymphadenopathies were noted. He was otherwise well, which contrasted with the severity\nof the cutaneous findings. Laboratory results revealed hemoglobin 127 g/L, white blood\ncell count 6.0 x 109 /L with 55% lymphocytes; an additional decrease in\nneutrophils (0.7 x 109 /L) and platelet count of 241 x 109 /L were\nnoted. Lactate dehydrogenase was elevated at 1139 U/L. Chest radiography was\nunremarkable. Thoracoabdomino-pelvic computerized tomography revealed enlargement of\nseveral mediastinal, axillary, celiac, retroperitoneal, obturator and inguinofemoral\nlymph nodes (some larger than 25 mm).\nHistology of skin and 2 cervical lymph nodes revealed a monomorphous, non-epidermotropic\ndiffuse infiltration of small-to-medium sized cells with pleomorphic nuclei () in the skin. This dense infiltrate effaced\nthe nodal architecture and was located in the dermis and hypodermis, separated from the\nepidermis by a grenz zone.\nBy immunohistochemistry, the cells coexpressed CD4, CD43, CD45 CD56, showed partial\npositivity for CD68 ( and ) and were negative for CD3, CD5, CD8, CD20, CD30,\nCD34, CD38, CD117, TDT, myeloperoxidase, light IgG chains and PAX5 (). The proliferative index (Ki-67) was high, approximately\n60%.\nBone marrow biopsy showed a markedly hypercellular marrow, with CD4+, CD43+,CD45+,\nCD56+, CD123+ and HLA-DR+ small blast cells accounting for 80% of cellularity. No\nexpressions of other T or B cell lineage were observed.\nBased on clinical and laboratory findings, the patient was diagnosed with BPDCN with\nextensive cutaneous, nodal and bone marrow involvement.\nSix cycles of CHOP (cyclophosphamide, adryamicine, vincristine, and prednisolone) were\nprescribed, with remission. Only post-therapy inflammatory reactive lesions remained on\nthe face and scalp.\nTwo months later, the disease relapsed. Left-sided brachial monoparesis developed and a\nparavertebral cervical (C2-C3) mass with medullary compromise through the intervertebral\nforamen was detected on magnetic resonance imaging. The patient was hospitalized in a\nstatus of rapid progression of the disease, with enlargement of the cervical mass,\nhyperleukocytosis (> 100.000/ml), mental status deterioration and died 7 months after\nthe diagnosis (9 months after onset of the first clinical symptoms).