Correlation of 18F-FDG PET/CT metabolic parameters with Ki-67 expression and tumor staging in nasopharyngeal carcinoma

Purpose The study aimed to investigate the imaging parameters of 18F-fluorodeoxyglucose ( 18 F-FDG) PET/computed tomography (PET/CT) in nasopharyngeal carcinoma (NPC), specifically examining the relationship between mean standardized uptake value (SUVmean), maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) with Ki-67 expression, T-stage, and tumor node metastasis (TNM) stage. Methods A retrospective analysis was conducted on 143 consecutive NPC patients from January 2015 to December 2023 who underwent 18 F-FDG PET/CT for initial disease assessment. SUVmax, SUVmean, MTV, and TLG were quantified from PET/CT images. Immunohistochemical staining was used to assess Ki-67 protein expression. Correlations between 18 F-FDG PET/CT metabolic parameters, Ki-67 expression, T-stage, and TNM-stage were evaluated using statistical methods, with significance set at P < 0.05. Results All primary NPC lesions demonstrated elevated 18 F-FDG uptake. Significant positive correlations were observed between SUVmax ( r = 0.234, P = 0.005), SUVmean ( r = 0.223, P = 0.007), MTV ( r = 0.218, P = 0.009), and TLG ( r = 0.232, P = 0.005) with Ki-67 labeling index. The univariate analysis indicated that all the parameters (SUVmax, SUVmean, MTV, and TLG) in the group with Ki-67 ≥ 50% were significantly higher than those in the group with Ki-67 < 50% ( P = 0.001). Additionally, binary logistic regression analysis revealed that SUVmax was an independent risk factor for the group with Ki-67 ≥ 50% ( P = 0.003). The univariate analysis revealed that all parameters (SUVmax, SUVmean, MTV, and TLG) in the T3–4 group and clinical stage IV group were significantly higher than those in the T1–2 group and stages I–III group ( P both <0.05), respectively. Furthermore, binary logistic regression analysis demonstrated that MTV was an independent risk factor for both comparisons ( P both <0.05). Conclusion The metabolic parameters derived from 18 F-FDG PET/CT in NPC indirectly reflect tumor biological behavior, suggesting their potential utility in guiding individualized comprehensive treatment strategies.