A simple prognostic scoring system for newly diagnosed cytogenetically normal acute myeloid leukemia: retrospective analysis of 530 patients.

We retrospectively analyzed the data of 337 patients with cytogenetically normal (CN) acute myeloid leukemia (AML), aged ≤ 65 years (training set). A prognostic index score (PIS) was calculated by totaling the score derived from the regression coefficients of each clinical variable, significantly associated with prognosis by multivariate analysis. The variables that were independent prognostic factors for event-free survival (EFS) and overall survival (OS) in the training set were: age ≥ 50 years, secondary AML and white blood cell count (WBC) ≥ 20 × 10(9)/L. The patients of the training set were stratified into three groups: low-, intermediate- and high-risk. The median EFS was 25, 12 and 7 months in the low-, intermediate- and high-risk groups (p < 0.0001), respectively. The median OS was not reached in the low-risk group and was 19 and 10 months in the intermediate- and high-risk groups (p < 0.0001). This PIS was validated in a series of 193 patients with CN-AML. The median EFS was 66, 16, and 3 months (p < 0.0001) and the median OS was 66, 16, and 5 months in the three risk groups, respectively (p < 0.0001). This PIS may be useful for clinical decision-making in CN-AML and may be prospectively integrated with the newest biological markers which at present are not routinely assessed and need prognostic validation.