Construction and validation of a nomogram model for predicting 60-day mortality in patients with acute myeloid leukaemia.

OBJECTIVE

To construct and internally validate a nomogram for predicting 60-day all-cause mortality in adult patients with de novo acute myeloid leukaemia (AML) and to compare its performance with European Leukaemia Network (ELN) 2022 risk stratification.

METHODS

Clinical data from 140 patients with newly diagnosed de novo AML treated at The First Affiliated Hospital of Henan Medical University between 2020 and 2025 were retrospectively analysed. Patients were allocated by stratified random split into a training cohort (n = 98; 21 death events) and an internal validation cohort (n = 42; 8 death events). Univariate and multivariate Cox proportional hazards regression were used consistently for time-to-event analysis. Proportional hazards assumptions were assessed using Schoenfeld residuals. Collinearity diagnosis, age-stratified subgroup analysis, treatment-intensity stratification, 200 bootstrap iterations and stratified 10-fold cross-validation were performed to evaluate model stability and reduce optimism. Discrimination, calibration, clinical utility and interpretability were assessed using time-dependent area under the curve (AUC), C-index, calibration curves, decision curve analysis and Shapley Additive Explanations (SHAP) analysis.

RESULTS

Twenty-nine patients (20.7%) died within 60 days. The final multivariate Cox model identified extramedullary disease (EMD) (hazard ratio [HR]=8.24, 95% confidence interval [CI]:1.91-35.63, P = 0.005), fibrinogen (per 100 mg/dL: HR = 1.12, 95%CI:1.04-1.21, P = 0.002), ferritin (per 200 ng/mL: HR = 1.09, 95%CI:1.02-1.17, P = 0.012) and number of positive prognostic genes (HR = 0.59, 95%CI:0.41-0.86, P = 0.006) as independent predictors. Bootstrap-corrected AUC/C-index values were 0.88/0.79 in the training cohort and 0.84/0.76 in the validation cohort; stratified 10-fold cross-validation yielded an average AUC of 0.87. The nomogram outperformed ELN 2022 risk stratification alone (AUC: 0.95 vs 0.74, P<0.001); SHAP analysis ranked EMD as the dominant feature.

CONCLUSION

This four-variable Cox nomogram showed favourable internally validated discrimination, calibration, clinical net benefit and interpretability for individualised 60-day mortality prediction in adult de novo non-acute promyelocytic leukaemia AML. Multicentre prospective external validation is warranted.