A Case Report of Mixed Phenotype Acute Leukemia with Plasmacytoid Dendritic Cell Proliferation.

BACKGROUND

The goal was to improve the understanding of mixed phenotypic acute leukemia (MPAL) complicated with plasmacytoid dendritic cell (PDC) proliferation.

METHODS

A case of mixed phenotype acute leukemia with plasmacytoid dendritic cell hyperplasia was reported. The clinical characteristics, treatment, and prognosis were analyzed by reviewing relevant literature.

RESULTS

The patient was a young female with clinical manifestations of splenomegaly and lymph node enlargement. The bone marrow smear showed hyperactive proliferation, 95% of protoblastic cells. The protoblastic cell body is large, more cell mass, stained gray blue, a small amount of azurophilicgranule can be seen in some cytoplasm, pseudopodia, drag tail, and other phenomena. The nucleus was twisted and folded. Chromatin is fine with nucleoli and Auer rods seen in the cytoplasm. Immune typing: Abnormal primordial cells accounted for 44.75%, and the primordial cells expressed both myeloid markers (CD33, CD13, MPO) and T-series markers (CD7, CD5, Ccd3), which were considered MPAL (M/T) according to WHO diagnostic criteria. In addition, a group of plasmoid dendritic cells occupied an increased proportion of 10.31% of nuclear cells. No obvious phenotypic abnormalities were observed. BCR/ABL fusion genes P190/P210 were negative. NRAS, NOTCH1, and DNMT3A mutations were detected by polymerase chain reaction. Combined with the above results, acute mixed cell leukemia (M/T) with plasmacytoid dendritic cell proliferation was diagnosed.

CONCLUSIONS

The diagnosis of mixed phenotype acute leukemia with plasmacytoid dendritic cell proliferation needs to be integrated with clinical manifestations, cytomorphology, immunology, cytogenetics, and molecular biology, etc. Disease should be diagnosed and treated as early as possible.