Early Metabolic Response Assessed Using 18F-FDG-PET/CT for Image-Guided Intracavitary Brachytherapy Can Better Predict Treatment Outcomes in Patients with Cervical Cancer

• Published in: Cancer research and treatment Vol. 53; no. 3; pp. 803 - 812
• Main Authors: Kim, Nalee, Park, Won, Cho, Won Kyung, Bae, Duk-Soo, Kim, Byoung-Gie, Lee, Jeong-Won, Kim, Tae-Joong, Choi, Chel Hun, Lee, Yoo-Young, Cho, Young Seok
• Format: Journal Article
• Language: English
• Published: Korea (South) Korean Cancer Association 01.07.2021; 대한암학회
• Subjects: Adenocarcinoma - diagnosis; Adenocarcinoma - metabolism; Adenocarcinoma - mortality; Adenocarcinoma - radiotherapy; Brachytherapy - methods; Disease-Free Survival; Female; Fluorodeoxyglucose F18 - administration & dosage; Follow-Up Studies; Humans; Middle Aged; Original; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals - administration & dosage; Radiotherapy Planning, Computer-Assisted; Risk Assessment - methods; Survival Rate; Uterine Cervical Neoplasms - diagnosis; Uterine Cervical Neoplasms - metabolism; Uterine Cervical Neoplasms - mortality; Uterine Cervical Neoplasms - radiotherapy; 의학일반; Image-guided brachytherapy; Uterine cervical neoplasms; Fluorodeoxyglucose F18; Radiotherapy
• ISSN: 1598-2998; 2005-9256; 2005-9256
• DOI: 10.4143/crt.2020.1251

Purpose This study aimed to identify the prognostic value of early metabolic response assessed using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) during radiation therapy (RT) for cervical cancer.Materials and Methods We identified 116 patients treated with definitive RT, including FDG-PET/CT–guided intracavitary brachytherapy, between 2009 and 2018. We calculated parameters including maximum (SUVmax) and mean standardized uptake values (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) for baseline FDG-PET/CT (PETbase) and image-guided brachytherapy planning FDG-PET/CT (PETIGBT). Multivariable analyses of disease-free survival (DFS) and overall survival (OS) were performed.Results We observed a time-dependent decrease in PET parameters between PETbase and PETIGBT; ΔSUVmax, ΔSUVmean, ΔMTV, and ΔTLG were 65%, 61%, 78%, and 93%, respectively. With a median follow-up of 59.5 months, the 5-year DFS and OS rates were 66% and 79%, respectively. Multivariable analysis demonstrated that ΔSUVmax ≥ 50% was associated with favorable DFS (hazard ratio [HR], 2.56; 95% confidence interval [CI], 1.14 to 5.77) and OS (HR, 5.14; 95% CI, 1.55 to 17.01). Patients with ΔSUVmax ≥ 50% (n=87) showed better DFS and OS than those with ΔSUVmax < 50% (n=29) (DFS, 76% vs. 35%, p < 0.001; OS, 90% vs. 41%, p < 0.001, respectively). Adenocarcinoma was frequently observed in ΔSUVmax < 50% compared to ΔSUVmax ≥ 50% (27.6% vs. 10.3%, p=0.003). In addition, models incorporating metabolic parameters showed improved accuracy for predicting DFS (p=0.012) and OS (p=0.004) than models with clinicopathologic factors.Conclusion Changes in metabolic parameters, especially those in SUVmax by > 50%, can help improve survival outcome predictions for patients with cervical cancer treated with definitive RT.