Predictive value of F-18 FDG PET/CT quantization parameters for progression-free survival in patients with diffuse large B-cell lymphoma.

OBJECTIVES: To evaluate the predictive significance of F-18 FDG PET/CT quantization parameters for progression-free survival (PFS) in patients with diffuse large B cell lymphoma (DLBCL) before chemotherapy.

METHODS: We conducted a retrospective study involving 60 patients with DLBCL between January 2010 and August 2014 who had undergone F-18 FDG PET/CT scan prior to treatment. Maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and number of enlarged lymph nodes (>2 cm) were measured. The primary outcome measure was PFS. Spearman rank correlation analysis, univariate and multivariate Cox regression models, receiver operating characteristic (ROC) analysis, and Kaplan-Meir survival curves were used.

RESULTS: Spearman analysis determined that the MTV and TLG values were positively related to Ann Arbor stage, National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) score, and lactate dehydrogenase (LDH) level. The number of enlarged lymph nodes was positively related only to LDH level. The SUVmax value and clinical characteristics were not related. Univariate Cox regression determined that the MTV and TLG values, number of enlarged lymph nodes, and NCCN-IPI score were predictive factors. Multivariate Cox regression determined that the MTV and TLG values and number of enlarged lymph nodes predicted PFS independently of the NCCN-IPI score. The SUVmax value was not predictive of PFS. According to the cut-off determined from ROC analysis, lower MTV and TLG values were highly predictive of favorable PFS.

CONCLUSIONS: In contrast to SUVmax, the MTV and TLG may be significant prognostic markers for PFS in DLBCL.