Purpose: This study aimed to evaluate the prognostic significance of fluorine-18 ( 18 F) fluorodeoxyglucose PET/computed tomography (CT) metabolic parameters in patients with primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL). Methods: We retrospectively analyzed 24 PGI-DLBCL patients treated with R-CHOP chemotherapy. Continuous variables were dichotomized at the median and compared using the t-test, whereas categorical variables e.g. gender, cell origin (germinal center B-cell/non-germinal center B-cell) were compared using the Chi-square test. Spearman correlation analysis was performed to examine relationships between metabolic parameters and potential prognostic factors. Univariate Kaplan–Meier survival analysis and multivariate Cox regression were used to identify independent prognostic factors for progression-free survival and overall survival. Prognostic differences among risk groups were also assessed. Results: Total lesion glycolysis (TLG), lactate dehydrogenase, International Prognostic Index (IPI), National Comprehensive Cancer Network-IPI, metabolic tumor volume (△MTV, representing changes in MTV between baseline and interim PET/CT), and clinical staging differed significantly between high and low-MTV groups (all P < 0.05).TLG, △MTV, lactate dehydrogenase, IPI score, National Comprehensive Cancer Network-IPI score, and clinical stage were significantly correlated with MTV (all P < 0.05). Receiver operating characteristic analysis indicated that MTV, standardized uptake value (△SUV max , changes in SUV max between baseline and interim PET/CT), TLG, and ΔMTV effectively predicted mid-term remission. Multivariate analysis identified MTV and ΔSUV max as independent predictors of progression-free survival ( P < 0.05), whereas ΔSUV max was independently associated with overall survival ( P < 0.05). Cox regression analysis revealed significant prognostic differences among subgroups ( P < 0.0001). Conclusion MTV, △SUV max , TLG, and △MTV are effective for evaluating for mid-term remission in PGI-DLBCL patients. Among them, MTV and △SUV max serve as independent prognostic factors.
LIN et al. (2026) studied this question.