Outcomes of Acute Lymphoblastic Leukemia with KMT2A (MLL) rearrangement - The MD Anderson Experience.

Abstract

Acute lymphoblastic leukemia (ALL) with t(4;11)(q21;q23) - KMT2A-AFF1 is associated with a poor prognosis. The impact of KMT2A rearrangements other than t(4;11) is uncertain and the benefit of allogeneic stem cell transplant (HSCT) is unclear. We reviewed adult patients with ALL treated at our institution from 1984 to 2019 and identified 50/1102 (5%) with KMT2A rearrangement: 42 (84%) with t(4;11)/KMT2A-AFF1 and 8 (16%) with other gene partners. The median age was 45 years old (range, 18 - 78 years); median white blood cell count was 109.0 x 109/L (range, 0.5 - 1573.0). The complete remission (CR) rate was 88% and the rate of measurable residual disease negativity by flow cytometry at CR was 41% (76% overall during follow-up). At the last follow-up, 14 patients were alive. The 5-year overall survival (OS) rate was 18% (95% CI, 9 - 35%) with no difference between t(4;11) and other KMT2A rearrangements (p=0.87). In a 4-month landmark analysis, the 5-year OS rate was 32% (95% CI, 14 - 70%) in patients who underwent HSCT versus 11% (95% CI, 3 - 39) in others (p=0.10). Our study confirms the poor prognosis of ALL with any KMT2A rearrangement and the role of HSCT in these patients.