Objective  To investigate the effect of pretreatment ¹⁸F-fluorodeoxyglucose (FDG) PET/CT parameters on disease remission in patients with diffuse large B-cell lymphoma (DLBCL) and construct a prediction model.

Methods  In this retrospective cohort study, the clinical and imaging data of 80 patients (including 44 males and 36 females, aged (63.0±11.4) years) with DLBCL admitted to Tangshan Central Hospital from February 2021 to February 2025 were analyzed. All patients were treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone regimen. Disease remission status was evaluated on the basis of ¹⁸F-FDG PET/CT findings after treatment completion. The patients were classified into complete remission and non-complete remission groups. The clinical characteristics and pretreatment ¹⁸F-FDG PET/CT parameters (maximum standardized uptake value (SUV_max), whole-body metabolic tumor volume (MTV_wb), and whole-body total lesion glycolysis (TLG_wb)) of the two groups were compared. Counting data were compared using the χ² test, and measurement data were compared via the independent samples t-test. Univariate and multivariate logistic regression analyses were performed to screen for the independent influencing factors of disease remission status in DLBCL patients after treatment, and a nomogram model was constructed. The receiver operating characteristic curve was used to evaluate the predictive performance of the model, and calibration and decision curves were employed to evaluate its clinical value.

Results Among the 80 patients, 29 (36.25%) and 51 (63.75%) were in the complete remission and non-complete remission groups, respectively. Univariate logistic regression analysis suggested that the two groups had statistically significant differences in the Ann Arbor stage, B symptoms, International Prognostic Index (IPI) score, serum lactate dehydrogenase level > upper limit of normal, cell proliferating nuclear antigen Ki-67 (hereinafter referred to as Ki-67), SUV_max, MTV_wb, and TLG_wb (χ²=5.922–11.716, t=3.399–15.095, all P<0.05). Multivariate logistic regression analysis showed that the IPI score (OR=2.804, 95%CI: 1.268–6.202), Ki-67 (OR=1.113, 95%CI: 1.011–1.225), SUV_max (OR=1.120, 95%CI: 1.009–1.242), and MTV_wb (OR=1.113, 95%CI: 1.013–1.223) were independent influencing factors of disease remission status in patients with DLBCL after treatment (all P<0.05). The area under the curve of the constructed nomogram model was 0.921 (95%CI: 0.853–0.988), with sensitivity of 0.918 and specificity of 0.836. The calibration and decision curves indicated that the model had high clinical reliability.

Conclusion The nomogram model constructed on the basis of pretreatment ¹⁸F-FDG PET/CT parameters has high clinical value in predicting disease remission in patients with DLBCL.