Comparison of the prognostic value of F-18 FDG PET/CT metabolic parameters of primary tumors and MRI findings in patients with locally advanced cervical cancer treated with concurrent chemoradiotherapy

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. 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. 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. 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.