Purpose: To evaluate the effect of metabolic parameters of pretreatment primary tumor and regional lymph nodes with F-18-FDG PET/CT compared with MRI findings for the prognostic value and disease-free survival (DFS) in locally advanced cervical cancer.
Material and methods: From 2011 to 2016, 112 patients with a diagnosis of cervical cancer stages IB2-IVA treated with concomitant chemoradiation therapy with 3D intracavitary brachytherapy were analyzed. From this group, 50 patients who underwent pretreatment and posttreatment FDG PET/CT and MRI were enrolled. LRFFS, DFS, and overall survival were analyzed in comparison with FDG PET/CT and MRI data. Relationship between SUVmax data and DFS was also assessed.
Results: The median followup was 21 months, and median age was 54 years. The estimated 5-year locoregional failure-free survival, DFS, and overall survival rates were 87.4%, 70%, and 81%, respectively. DFS was 59.5% in patients with nodal metastases in FDG PET/CT and 100% in node negative patients (p:0,017). DFS was 50% and 79.4% in MRI node-positive and in node-negative patients, respectively (p:0,260). In addition, the nodal SUVmax (p: 0.005) and posttreatment response in FDG PET-CT (p < 0.001) were significant prognostic factors for DFS. Furthermore, primary tumor volume in MRI (p:0,982), node positivity in MRI (p:0,301), and response in posttreatment MRI (p:0,26) are not significant prognostic factors for DFS.
Conclusion: As a result, FDG PET/CT has higher accuracy than MRI in detecting lymph node metastasis, and tumor volume reduction on FDG PET/CT images was greater than that on MRI images after CCRT.
Keywords: Cervical cancer; F-18 FDG PET-CT; MRI; Radiation therapy.
Copyright © 2018 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.