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

Abstract

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.