International Journal of Clinical Research

Objective To compare the predictive value of changes in metabolic parameters of 18F-PET/CT before treatment (baseline) and after 4 cycles of chemotherapy (interim), combined with the Deauville five-point scale, for prognostic assessment in DLBCL. Methods From March 2020 to October 2024, a retrospective analysis was conducted on 44 patients with pathologically confirmed diffuse large B-cell lymphoma [including 25 males and 19 females, with a median age of 59 (17-83) years]. All patients underwent 18F-PET/CT scans before treatment and after 4 cycles of chemotherapy. The relevant metabolic parameters from both scans were collected, and the absolute changes and percentage changes in each parameter were calculated. ROC curves were used to determine optimal cutoff values, and patients were grouped based on these thresholds for Kaplan-Meier survival analysis and COX regression analysis. After 4 cycles of chemotherapy, another 18F-PET/CT scan was performed, and each patient was scored using the Deauville five-point scale. Patients were divided into two groups: scores 1-3 in one group and scores 4-5 in another, followed by Kaplan-Meier survival analysis and COX regression analysis. The chi-square test was used for comparative data analysis. Results (1) Among the 44 patients, 11 experienced disease progression during follow-up. The median △LLR% in the progression group was 50.00% (5.00%~86.00%), significantly lower than that in the non-progression group (84.00% [60.50%~92.50%]) (z=-2.36, P<0.05). (2) The optimal cutoff value for △LLR% was 60.5%. (3) Significant differences in 2-year PFS were observed between the △LLR% ≥60.5% and <60.5% groups, as well as between the Deauville score ≥4 and <4 groups (χ²=5.529, 7.729, both P<0.05). Conclusion Both △LLR% and the Deauville five-point scale have predictive value for the prognosis of DLBCL, with △LLR% being an independent influencing factor in multivariate analysis. The combination of △LLR% and the Deauville five-point scale can provide better prognostic evaluation for patients.

Diffuse large B-cell lymphoma; Positron emission tomography; Metabolic parameters; Prognosis