How should we diagnose and treat blastic plasmacytoid dendritic cell neoplasm patients?

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive leukemia for which we developed a nationwide network to collect data from new cases diagnosed in France. In a retrospective, observational study of 86 patients (2000-2013), we described clinical and biological data focusing on morphologies and immunophenotype. We found expression of markers associated with plasmacytoid dendritic cell origin (HLA-DRhigh, CD303+, CD304+, and cTCL1+) plus CD4 and CD56 and frequent expression of isolated markers from the myeloid, B-, and T-lymphoid lineages, whereas specific markers (myeloperoxidase, CD14, cCD3, CD19, and cCD22) were not expressed.

From the observation of atypical cells on blood smear to the diagnosis of mast cell leukemia: a case report in a 79 year old woman consulting for anemia.

Mast cell leukemia is an extremely rare disease, which belongs to the systemic mastocytosis group (WHO 2016). We are reporting the case of a 79-year-old woman, without any hematological particular history consulting for hyperthermia, repeated malaise and subacute anemia. Her clinical examination was normal.

Burkitt cells on a peripheral blood smear: how to deal with?

The diagnosis of double hit lymphoma remains a challenge for the biologist for a good management of the patient. This new category of lymphoma "double hit" (DH) is part of a new entity of the WHO classification 2008: « Unclassifiable B lymphoma with features intermediate between diffuse large cell B lymphoma and Burkitt's lymphoma ». It is defined by the presence of a breakpoint at the locus 8q24 of the c-MYC gene associated with a recurrent translocation involving BCL2 genes primarily BCL6 or more rarely CCDN1 or BCL3 genes.

In vivo and in vitro sensitivity of blastic plasmacytoid dendritic cell neoplasm to SL-401, an interleukin-3 receptor targeted biologic agent.

Blastic plasmacytoid dendritic cell neoplasm is an aggressive malignancy derived from plasmacytoid dendritic cells. There is currently no accepted standard of care for treating this neoplasm, and therapeutic strategies have never been prospectively evaluated. Since blastic plasmacytoid dendritic cell neoplasm cells express high levels of interleukin-3 receptor α chain (IL3-Rα or CD123), antitumor effects of the interleukin-3 receptor-targeted drug SL-401 against blastic plasmacytoid dendritic cell neoplasm were evaluated in vitro and in vivo.

[WHIM syndrome: presumptive diagnosis based on myelokathexis on bone marrow smear].

The WHIM syndrome is a rare congenital immunodeficiency disorder characterized by human papillomavirus (HPV)-induced warts, hypogammaglobulinemia, bacterial infections and myelokathexis. Myelokathexis refers to abnormal retention of mature neutrophils in the bone marrow leading to severe neutropenia. We report the case of a 20 year old man presenting with chronic and severe neutropenia since early childhood without established diagnosis.

Epigenetic control of NF-κB-dependent FAS gene transcription during progression of myelodysplastic syndromes.

The death domain containing TNF receptor 6 (CD95/Fas) is a direct target for the NF-κB transcription factor and is repressed in solid tumors such as colon carcinomas. Previously, we reported that the Fas death receptor, while overexpressed in low-risk myelodysplastic syndromes (MDS), becomes undetectable on CD34(+) progenitors when the disease progresses to secondary acute myeloid leukemia (AML). This study determined the interplay between NF-κB and Fas during MDS progression.

[Usefulness of gray platelets observation in ARC syndrome].

Arthrogryposis Renal Fanconi syndrome and Cholestasis (ARC syndrome) is an extremely rare disease (62 cases) and is uneasy to diagnose. This congenital multisystem disorder affects newborns who usually die in the first year of life. The three cases here report the main clinical and biological features of this unknown disease and show how careful platelets morphology examination on blood smear can help for diagnosis.