The diagnostics of blastic plasmocytoid dendritic cell neoplasm: report of five cases

Abstract

The diagnosis of rare hematological disorders requires a comprehensive clinical and laboratory investigation with careful interpretation of all test results. Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is one of such rare entities. We have performed a retrospective analysis of the results of immunophenotyping, cytomorphology and cytogenetics of bone marrow tumor cells from 5 patients with BPDCN aged from 8 to 51 years. The study was approved by the Independent Ethics Committee of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology. No specific characteristics of blasts were found. No correlation with the treatment and outcomes was noted as well: 3 patients died of progression or relapse (2 and 1, respectively). Bone marrow immunophenotyping is probably the most valuable laboratory test which allows physicians to establish the proper diagnosis in the absence of skin lesions. Flow cytometry immunophenotyping is the only technique used to determine the antigen profile that enables us to distinguish normal plasmacytoid dendritic cells from tumor ones by the presence (or absence) of the expression of CD2, CD7, CD38, CD56, CD303 etc. In the present paper, we provide a detailed description of five cases of BPDCN and main methods for flow cytometry data analysis. The parents of the patients agreed to use the information, including photos of children, in scientific research and publications.