Allogeneic Hematopoietic Stem Cell Transplantation Can Improve Prognosis of Extramedullary Infiltration Positive t(8;21) Acute Myeloid Leukemia

Background: In t(8;21) acute myeloid leukemia (AML), patients with extramedullary infiltration (EMI) tend to have worse survival outcomes than those without EMI. However, it is still unclear whether allogeneic hematopoietic stem cell transplantation (allo-HSCT) benefits EMI-positive t(8;21) AML patients.Material/Methods: This study retrospectively enrolled 651 t(8;21) AML patients, and analyzed 51 patients with EMI at diagnosis. Among the 51 patients, 15 patients received allo-HSCT.Results: The incidence of EMI in t(8;21) AML was 10.0%, and the first complete remission rate was 78.5% in EMI-positive t(8;21) AML patients. The central nervous system was the most frequently involved site (29.4%), followed by bones (15.7%), and skin (9.8%). In terms of karyotype, 19 (37.3%) patients were t(8;21) alone, 12 (23.5%) had additional loss of a sex chromosome, and 5 (9.8%) had complex karyotype. Significantly better overall survival was observed in patients with allo-HSCT compared to patients without allo-HSCT in both multivariable models (HR=0.32; P=0.0122) and the Kaplan-Meier curves (P=0.0157).Conclusions: Allo-HSCT improved the survival of EMI-positive t(8;21) AML.