A Case of Acute Lymphoblastic Leukemia with Maturation

ABSTRACT

Acute lymphoblastic leukemia with maturation (ALLm) has different disease characteristics that does typical ALL. ALLm is characterized by an increased number of mature appearing leukemic cells (>20% of ANCs in the BM) having differentiation beyond the prolymphocyte stage according to light microscopic (LM) examination. It also has a worse prognosis than typical ALL. We have recently experienced a case of ALLm and we report on this case along with a literature review. A 36 year old patient showed lymphoblasts and mature appearing leukemic cells that were counted up to 15.8% and 23.0%, respectively, of the WBCs on bone marrow examination. Despite their mature appearance, these cells showed positivity for Tdt, CD10, CD19 and HLA-DR on the immunophenotypic study. Differentiating the mature-appearing leukemic cells from the hematogones or mature lymphocytes is difficult, and only through immunophenotypic examination is it possible to discriminate ALLm from typical ALL. We suggest performing a leukemic marker study that includes CD38 to effectively differentiate mature appearing leukemic cells from hematogones, especially for the follow up of leukemia with mature appearing cells.