Monocytes appearing repeatedly after chemotherapies had an identical rearrangement pattern of immunoglobulin with leukemic blasts in a patient with CD13+ acute lymphoblastic leukemia.
CD13 is commonly expressed in hematopoietic malignancies of myelomonocytic origin and has less commonly been described in lymphoid neoplasms, including acute lymphoblastic leukemia, B-cell lymphoproliferative disorders, and plasma cell malignancies.
CD13/APN expression in some ALL at diagnosis could result from a block in the signal transduction pathways that cause its suppression by bone marrow stromal cells.
We report on a case of a 30-year-old male with acute B-lymphoblastic leukemia (B-ALL) with immunophenotype CD19(+), CD22(+), CD20(+), CD10(+), with aberrant expression of CD13 and CD117, and IgH gene rearrangements.