Utility of 2-[18F]Fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography in assessing treatment response after chemoradiotherapy for cervical cancer.

Cervical cancer is the fourth most common malignancy globally. As many cases are locally advanced, early prediction of local recurrence, which often occurs within 2 years of chemoradiotherapy (CCRT), is crucial. The National Comprehensive Cancer Network Guidelines recommend post-treatment 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18F-FDG-PET/CT) for response assessment, but this is not standard in Japan. We aimed to investigate the utility of 18F-FDG-PET/CT in assessing primary tumor response after CCRT for cervical cancer. Seventy-three patients with cervical cancer who received curative CCRT and underwent pre- and post-treatment magnetic resonance imaging and 18F-FDG-PET/CT were analyzed. We collected PET metrics (maximum standardized uptake value [SUVmax], metabolic tumor volume [MTV], total lesion glycolysis [TLG]) and classified the response. Receiver operating characteristic (ROC) curve analysis was performed on the post-treatment PET data. Univariate analysis was performed to determine the prognostic factors for local control. ROC curve analysis yielded high negative predictive values for local recurrence of post-treatment MTV, SUVmax and TLG. Univariate analysis showed significant differences in local control for post-treatment MTV, SUVmax, TLG and PET Response Criteria in Solid Tumors, but not for Response Evaluation Criteria in Solid Tumors (RECIST). Functional assessment using 18F-FDG-PET/CT after CCRT for cervical cancer is useful for complementing conventional morphological evaluation and improving the accuracy of response assessment.