Enhancement of the International prognostic index with β2-microglobulin, platelet count and red blood cell distribution width: a new prognostic model for diffuse large B-cell lymphoma in the rituximab era

• Published in: BMC cancer 2022-05, Vol.22 (1), p.583-583, Article 583
• Main Authors: Chen, Haizhu, Zhong, Qiaofeng, Zhou, Yu, Qin, Yan, Yang, Jianliang, Liu, Peng, He, Xiaohui, Zhou, Shengyu, Zhang, Changgong, Gui, Lin, Yang, Sheng, Zhou, Liqiang, Shi, Yuankai
• Format: Article
• Language: English
• Subjects: Automation; B-cell lymphoma; Blood; Blood platelets; Chemotherapy; Creatinine; Diffuse large B-cell lymphoma; Erythrocytes; Hemoglobin; Humans; Immunotherapy; International prognostic index; Lymphocytes; Lymphocytes B; Lymphoma; Lymphoma, Large B-Cell, Diffuse - drug therapy; Medical prognosis; Monoclonal antibodies; Multivariate analysis; Neutrophils; Patients; Platelet Count; Platelets; Prognosis; Red blood cell distribution width; Retrospective Studies; Risk groups; Rituximab; Rituximab - therapeutic use; Targeted cancer therapy; β2 Microglobulin
• ISSN: 1471-2407; 1471-2407
• DOI: 10.1186/s12885-022-09693-z

This study aimed to propose a new user-friendly, cost effective and robust risk model to facilitate risk stratification for diffuse large B-cell lymphoma (DLBCL) treated with frontline R-CHOP regimens. Data on 998 patients with de novo DLBCL diagnosed between Jan 1st, 2005 and Dec 31st, 2018 at our center, who received frontline R-CHOP or R-CHOP-like regimens, were retrospectively collected. Patients were randomly divided into the training cohort (n = 701) and the validation cohort (n = 297). A new prognostic model for overall survival (OS) was built based on the training cohort. The performance of the new model was compared with International prognostic index (IPI), revised IPI (R-IPI) and National Comprehensive Cancer Network (NCCN)-IPI (NCCN-IPI). The new model was validated in the validation cohort. The multivariate analysis of the training cohort showed that the IPI, β2-microglobulin, platelet count and red blood cell distribution width were independent factors for OS, which were incorporated into the new prognostic model. Patients were stratified into low risk, low-intermediate risk, high-intermediate risk, high risk and very high risk groups, with distinct survival outcomes. The new model achieved good C-indexes for 5-year OS prediction of 0.750 (95%CI 0.719-0.781) and 0.733 (95%CI 0.682-0.784) in the training and validation cohorts, respectively, and displayed well-fitted calibration curves. The C-index and the time-dependent ROC analysis demonstrated better performance of the new model than the IPI, R-IPI and NCCN-IPI in both training and validation cohorts. The integrated Brier score for predicting 5-year OS of the new model was lower than that of the IPI, R-IPI and NCCN-IPI in both cohorts, and decision curve analysis also showed a higher net benefit, indicating the superiority of the new model over the conventional models. The new prognostic model might be a useful predictive tool for DLBCL treated with R-CHOP regimens. Further external validation is warranted.