No Adverse Effect of Residual Neoplastic Mast Cells in Systemic Mastocytosis Associated with Acute Myeloid Leukemia with T(8;21) (Q22;Q22); Runx1-Runx1t1 after Bone Marrow Transplantation - Abstract
Mast cells are often increased in acute myeloid leukemia (AML) with t(8;21), however, concurrent development of systemic mastocytosis (SM) is rare. Here we report the case of a 22-year-old man with concurrent AML and SM. Although he achieved remission with chemotherapy, he relapsed with development of a myeloid sarcoma in the brain. After successful matched sibling hematopoietic stem cell transplant, neoplastic mast cells carrying both the RUNX1-RUNX1T1 translocation and the c-kit point mutation D816 V persisted in the marrow for up to 18 months after transplantation. Despite this, leukemia remains in continuous complete remission for 8.75 years. This observation suggests that neoplastic mast cells in SM-AML with t(8;21) have no adverse effect on hematopoiesis after bone marrow transplantation.