Risk Stratification for Diffuse Large B-Cell Lymphoma Integrating Interim ¹⁸f-FDG PET-CT Analysis and the National Comprehensive Cancer Network IPI: A Multicentre Retrospective Study

The treatment of diffuse large B-cell lymphoma (DLBCL) requires an accurate interim assessment of therapeutic effect. The prognostic evaluation of interim 18F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography-computed tomography (PET-CT) remains controversial. Our objective was to assess the prognostic significance of the interim National Comprehensive Cancer Network International Prognostic Index (iNCCN-IPI) and PET-CT-related parameters in predicting patient outcomes and to achieve accurate risk stratification. In this study, we retrospectively analysed the clinicopathological and PET-CT data of 498 patients diagnosed with DLBCL across three medical centres in China. The change in total lesion glycolysis (ΔTLG), the iNCCN-IPI, interim abdominal residual disease (iARD) status, and the change in the maximum standardized uptake value (∆SUVmax) were identified as independent prognostic factors via univariate and multivariate Cox regression analyses. The prognostic significance of these variables was corroborated via machine learning classifiers. Based on the results of multivariate analysis, we developed a prognostic model, iPET-NCCN-IPI, which stratifies DLBCL patients into two distinct prognostic risk groups. The predictive performance of the model was validated by calculating the area under the receiver operating characteristic curve (AUC) and the C-index via the bootstrap resampling method. Additionally, compared with the Deauville score, iPET-NCCN-IPI demonstrated superior prognostic capability, distinguishing potentially poor prognostic outcomes among patients with a Deauville score of 3. In conclusion, we demonstrated that the NCCN-IPI and PET-CT-related parameters at interim evaluation are independent prognostic factors for DLBCL patients. Compared with the Deauville score, the newly developed prognostic tool iPET-NCCN-IPI has superior prognostic predictive ability and can be used to identify patients with potentially poor prognoses among those with a Deauville score of 3.

No relevant conflicts of interest to declare.