Purpose: Rituximab with cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) represents the standard of care for first-line treatment of diffuse large B-cell lymphoma (DLBCL). However, many patients are unable to tolerate R-CHOP and have inferior outcomes. This study aimed to develop a practical tool to help physicians identify patients with newly diagnosed DLBCL unlikely to tolerate a full course of R-CHOP.
Methods: We developed a predictive model (Tolerability of R-CHOP in Aggressive Lymphoma [TRAIL]) on the basis of a training data set from the phase III GOYA trial (obinutuzumab with CHOP v R-CHOP in 1L DLBCL) using a composite binary end point, identifying patients who prematurely stopped or required reductions of R-CHOP. Candidate predictive variables were selected on the basis of known baseline characteristics that contribute to patient frailty, comorbidity, and/or chemotherapy toxicity. TRAIL was developed using an iterative trial-and-error modeling process to fit a logistic regression model. The final model was evaluated for robustness using a GOYA holdout data set and the phase III MAIN (R-CHOP with or without bevacizumab in 1L DLBCL) R-CHOP-21 data set as external validation.
Results: TRAIL includes four simple predictors available in the routine clinical setting: Charlson Comorbidity Index, presence of cardiovascular disease or diabetes, serum albumin, and creatinine clearance. Model generalization performance estimated by the area under the curve was around or above 0.70 across GOYA training, GOYA holdout, and MAIN data sets. Classifying patients into low-, intermediate- and high-risk categories, the proportion of patients experiencing a tolerability event was 3.3%, 12.4%, and 32.9%, respectively, in GOYA holdout, and 9.7%, 9.7%, and 34.2%, respectively, in MAIN.
Conclusion: TRAIL may be useful as a clinical decision support tool for treatment decisions in patients with DLBCL who may not tolerate standard chemoimmunotherapies.