Objective: The goal of the present study was to determine whether the volumetric parameters such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG) measured by F-FDG PET/CT could be used as prognostic factors for the recurrence-free survival (RFS) and overall survival (OS) in patients with surgically resected rectal cancer.
Patients and methods: A retrospective review identified 73 patients with surgically resected rectal cancer who received F-FDG PET/CT. Survival analysis was conducted using Kaplan-Meier analysis, and survival curves stratified by age, sex, lymph node status, surgical resection margin, American Joint Committee on Cancer (AJCC) stage, and volumetric parameters of F-FDG PET/CT were generated for the estimation of OS and RFS. Independent predictive factors for survival were determined using Cox proportional hazards model.
Results: High MTV, high TLG, advanced AJCC stage, lymph node (+), and surgical margin (+) group showed shorter OS in rectal cancer patients. Cox proportional hazards regression analysis showed that only surgical margin (+) was associated with poor OS. The early AJCC stage, lower MTV, and lower TLG were associated with better RFS in the current study. Cox proportional hazards regression analysis reveals that the surgical margin (+) was the potent predictor of OS. However, none of the factors was associated with RFS.
Conclusions: In conclusion, the results of this study suggest that volumetric parameters of F-FDG PET/CT could be significant prognostic factors in surgically resected rectal cancer.