Abstract
Acute myeloid leukemia (AML) with rearrangement of the lysine methyltransferase 2a gene (KMT2Ar) has adverse outcomes. However, reports on the prognostic impact of various translocations causing KMT2Ar are conflicting. Less is known about associated mutations and their prognostic impact. In a retrospective analysis, we identified 172 adult patients with KMT2Ar AML and compared them to 522 age-matched patients with diploid AML. KMT2Ar AML had fewer mutations, most commonly affecting RAS and FLT3 without significant impact on prognosis, except for patients with ≥2 mutations with lower overall survival (OS). KMT2Ar AML had worse outcomes compared with diploid AML when newly diagnosed and at relapse, especially following second salvage (median OS of 2.4 vs 4.8 months, P < 0.0001). Therapy-related KMT2Ar AML (t-AML) had worse outcomes compared with de novo KMT2Ar AML (median OS of 0.7 years vs 1.4 years, P < 0.0001). Allogeneic hematopoietic stem cell transplant (allo-HSCT) in first remission was associated with improved OS (5-year, 52 vs 14% for no allo-HSCT, P < 0.0001). In a multivariate analysis, translocation subtypes causing KMT2Ar did not predict survival, unlike age and allo-HSCT. In conclusion, KMT2Ar was associated with adverse outcomes regardless of translocation subtype. Therefore, AML risk stratification guidelines should include all KMT2Ar as adverse.