A Prognostic Nomogram Survival Model for Newly Diagnosed Patients with AIDS-Related Diffuse Large B-Cell Lymphoma: A Multicenter Cohort Study in China

Abstract

BACKGROUND The prognosis of patients with AIDS-related diffuse large B-cell lymphoma(AR-DLBCL) becomes very poor when the lymphoma relapses or is refractory to first line immunochemotherapy. We aimed to develop a novel ARDPI nomogram prognostic model for risk stratification so as to guide individualized treatment to achieve sustained remission and improve the overall prognosis for newly-diagnosed AR-DLBCL patients. METHODS We interrogated data from 306 patients with newly-diagnosed AR-DLBCL. We filtered variables using LASSO regression and Cox regression to identify prognostic co-variates and develop a survival model, we termed AR-DLBCL Prognostic Index (ARDPI). We evaluated model discrimination, calibration and clinical benefit by Area Under the Receiver-Operator Characteristic (AUROC), calibration plots and decision curve analysis (DCA). Next, we compared the ARDPI model discrimination, calibration and clinical benefit with the IPI and NCCN-IPI models using the same methods. Lastly, we stratified patients into three survival risk cohorts based on ARDPI model by X-tile selecting cutoff point. RESULTS 7 co-variates were independently correlated with survival and were used to develop the ARDPI model including age, lymphocyte monocyte ratio (LMR), CD5 expression on lymphoma cells, blood EBV-DNA copy number, CD4/CD8 ratio, central nervous system (CNS) involvement and anti-HIV therapy (ART). AUROCs of ARDPI model for 1-, 3-, and 5-year were 0.80 (95% Confidence Interval [CI], 0.72, 0.88), 0.78 (0.69, 0.87) and 0.77 (0.63, 0.91). Predicted and calibrated values were concordant. The DCA curve had higher net benefit using the ARDPI model. Prediction accuracy of the ARDPI model was better compared with the IPI and NCCN-IPI models. For example, 3-year survival AUROC in the ARDPI model was 0.78 (0.69, 0.87) compared with the IPI (0.53 [0.43, 0.63] P< 0.001) and the NCCN-IPI (0.52 [0.42, 0.62] P< 0.001). Using the ARDPI model, we identified 3 survival risk cohorts with 3-year survivals of 0.80 , 0.38 and 0.09 ( P<0.001). CONCLUSION The ARDPI has good survival prediction accuracy in newly-diagnosed persons with AIDS-related DLBCL and using it has clinical benefit.Accuracy is better than the IPI and NCCN-IPI models. Validation of our conclusions is needed.