Abstract 835P
Background
This study aimed to propose a new user-friendly and robust prognostic model for diffuse large B-cell lymphoma (DLBCL) treated with R-CHOP regimens.
Methods
Data on 1019 de novo DLBCL patients diagnosed between Jan 1st, 2005 and Dec 31st, 2018 at our center, who were treated with R-CHOP, were retrospectively collected. Patients were randomly divided into the training (n=715) and the validation cohort (n=304). 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 NCCN-IPI. The new model was validated in the validation cohort.
Results
The multivariate analysis of the training cohort showed that IPI, β2-microglobulin (β2M), platelets (PLT), red blood cell distribution width (RDW) were independent factors for OS. A new model was constructed with these variables: IPI (low-intermediate risk, 2 points; high-intermediate risk, 3 points; high risk, 5 points), elevated β2M, PLT<157 and RDW<14.5, with 1 point each for the last three factors. In the training cohort, patients were stratified into low risk (0 point, n=288), low-intermediate risk (1 point, n=87), high-intermediate risk (2-3 points, n=179), high risk (4 points, n=56) and very high risk (≥5 points, n=105) groups, with 5-year OS of 91.0%, 78.5%, 66.7%, 48.0% and 29.4%, respectively (P<0.001). Also, patients in the validation cohort had distinct 5-year OS of 90.0%, 75.6%, 64.8%, 47.9% and 26.7% for the five risk groups, respectively. The new model achieved good C-indexes for 5-year OS prediction of 0.749 and 0.728 in the training and validation cohorts, respectively, and displayed well-fitted calibration curves. The AUC of the new model for OS prediction at specific time points (6 months to 10 years) was consistently and significantly higher than that of the conventional models in both cohorts. Moreover, the integrated Brier score and decision curve analysis also indicated that the new model displayed better performance.
Conclusions
The new prognostic model might be a useful predictive tool for DLBCL treated with R-CHOP regimens. Further validation in independent or prospective cohorts is needed.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.