Objective To investigate the value of ¹⁸F-FDG PET/CT metabolic parameters in the prognostic assessment of nasopharyngeal cancer patients.

Methods The clinical data and PET/CT metabolic parameters of 185 nasopharyngeal cancer patients were retrospectively analyzed. The collected parameters were SUV_max, MTV, TLG, total metabolic tumor volume (TMTV) and whole-body total lesion glycolysis (WTLG). The ROC curve was used to determine the optimal cut-off values of PET/CT metabolic parameters. Univariate and multivariate Cox regression models were used to screen the independent prognostic factors. Kaplan–Meier curves were used to analyze the survival differences.

Results The results of univariate Cox regression analysis showed that age, pathologic type, WTLG, TMTV, MTV, and TLG were closely associated with OS and PFS; and SUV_max was associated with PFS (P<0.05). Multivariate Cox regression analysis results showed that age, TMTV, and WTLG were the independent prognostic factors for OS and PFS (P<0.05). The combination of WTLG with T/N staging (AUC=0.781 and 0.781) and TMTV with T/N staging (AUC=0.800 and 0.790) yielded greater predictive accuracy than that of WTLG and TMTV alone (AUC=0.724 and 0.719) or T/N staging (AUC=0.593 and 0.575).

Conclusion TMTV and WTLG are important prognostic predictors of nasopharyngeal carcinoma. TLG and MTV of primary lesions are prognostic factors for patients’ PFS and OS. SUV_max has limited prognostic value. Systemic metabolic indexes (TMTV and WTLG), when combined with T/N staging, can optimize prognostic stratification.