The influence of age on prognosis of de novo acute myeloid leukemia differs according to cytogenetic subgroups

Abstract

BACKGROUND AND OBJECTIVES: In the presented study the effect of age and cytogenetics on clinical outcome in acute myeloid leukemia (AML) was evaluated. The 1225 patients with de novo AML were separated according to age as follows: A1: 16 to 49 years (n=442), A2: 50 to 59 years (n=246), A3: 60-69 years (n=333), A4: 70 years and older (n=204). DESIGN AND METHODS: Patients were categorized with respect to cytogenetics into 5 groups: C1: t(15;17) (n=107), C2: CBF-AML/inv(16)/t(8;21) (n=171), C3: 11q23/MLL (n=42), C4: complex aberrant karyotype (n=130), C5: other: normal, other abnormalities, 5q-/-5, 7q-/-7, inv(3)/t(3;3), other 3q abnormalities (n=746). For each age category univariate cox regression analysis was performed using age as a continuous variable and C1 to C5 as dichotomous variables. RESULTS: In cohort A1 all parameters were significantly associated with overall survival (OS). However, in multivariate analysis all cytogenetic parameters were independently correlated with OS, while age was not. In cohort A2 only CBF and complex aberrant karyotype were significantly correlated with OS. In A3 t(15;17), complex karyotype and age, and in A4 only complex karyotype and age were significantly associated with OS in univariate and multivariate analyses. Within all cytogenetic subgroups except AML 11q23/MLL there were significant associations between age and OS. INTERPRETATION AND CONCLUSIONS: (i) Both age and cytogenetics are independent prognostic parameters in AML;(ii) up to the age of 49 years age has no major impact on prognosis while the karyotype has; (iii) in patients 50 years and older the influence of age on outcome increases, and (iv) cytogenetics show an independent effect on survival also in patients over 60 years old.