Retrospective Analysis of a New Prognostic Score for Diffuse Large B-Cell Lymphoma Based on Interim Positron Emission Tomography-Computed Tomography

Improved prediction of chemoresistance in patients with diffuse large B-cell lymphoma through a new interim positron emission tomography-computed tomography evaluation model

OBJECTIVES

The positron emission tomography (PET) could predict the prognosis of DLBCL patients, but the exact procedure on interim PET (iPET) to determine chemoresistant patients remains elusive.

METHODS

We retrospectively analyzed 593 newly diagnosed DLBCL patients uniformly treated with R-CHOP regimen. Among them, 352 patients diagnosed from August 2010 to December 2016 were included in the test cohort and 241 patients diagnosed from January 2017 to December 2019 were included in the validation cohort. The iPET was evaluated with Deauville criteria and ΔSUVmax method. The reduction of maximal SUV between baseline and after 4 cycles of chemotherapy were defined as ΔSUVmax. The survival functions were depicted using the Kaplan-Meier method and compared with the log-rank test.

RESULTS

Patients with iPET Deauville 4 had heterogeneous outcome and end of treatment complete response rates (eCRR). Combined Deauville with ΔSUVmax method, we proposed a modified-Deauville model: patients with Deauville 4 and ΔSUVmax > 70%, as well as those with Deauville 1-3, were reclassified into the modified-Deauville negative group, while patients with Deauville 4 and ΔSUVmax ≤ 70%, as well as those with Deauville 5, into the modified-Deauville positive group. In the test cohort, 3-year PFS, OS and eCRR of modified-Deauville negative group were 80.2%, 89.9% and 91.8%, significantly higher than those of positive group (12.5%, 27.3% and 29.2%, p ≤ .001). Similar results were found in the validation cohort, that 3-year PFS, OS and eCRR were 87.8%, 95.4%, 96.3% in modified-Deauville negative group, and 27.4%, 32.5%, 13.5% in positive group. Through modified-Deauville model, patients in iPET positive group had very low eCRR and were resistant to conventional chemotherapy.

CONCLUSIONS

The modified-Deauville model could better distinguish DLBCL patients with poor response to chemotherapy. Accordingly, these patients could be recognized early and provided with alternative therapeutic agents, which might improve the clinical outcome of refractory DLBCL patients.

Available prognostic models for risk stratification of diffuse large B cell lymphoma patients: a systematic review

The International Prognostic Index (IPI) has been used for risk stratification for a long time in diffuse large B cell lymphoma (DLBCL). Based on new clinical and biological prognostic markers, many new prognostic models have been described. This review aims to present the progress in development and validation of these prognostic models. A comprehensive literature review was performed to identify studies that proposed a new prognostic model in DLBCL. A total of 38 studies met the inclusion criteria. The IPI, revised IPI (R-IPI), and National Comprehensive Cancer Network (NCCN)-IPI were the most studied prognostic indexes, externally validated and commonly used to compare to other models. Despite an increasing number of prognostic models have been proposed lately, most of them lack external validation. Further studies, that combine biological and clinical markers with prognostic significance, are needed to determine the optimal prognostic tool for more personalized treatment approach to DLBCL patients.