Use of Functional Magnetic Resonance Imaging in Cervical Cancer Patients With Incomplete Response on Positron Emission Tomography/Computed Tomography After Image-Based High-Dose-Rate Brachytherapy

Abstract

Purpose: To investigate the correlation between positron emission tomography/computed tomography (PET/CT) response and outcome in the era of magnetic resonance imaging (MRI)-based planning and to assess whether the addition of diffusion-weighted MRI (DW-MRI) could more accurately classify treatment response and prognosis. Methods and Materials: A retrospective chart review identified 244 consecutive patients with International Federation of Gynecology and Obstetrics stage IB1-IVA cervical cancer treated with concurrent chemoradiation, including high-dose-rate image-based brachytherapy, between 2007 and 2016. Image-based brachytherapy was delivered with 5 intracavitary/interstitial fractions, each 5 to 6 Gy per fraction. Results: An complete response on posttreatment PET/CT (PET-CR) was discovered in 50 of 244 patients (20%) at a median interval of 3.3 months (range, 2.1-7.7 months) after treatment. After a median follow-up of 27 months, 2-year overall survival was 83% in all patients. Metabolic response significantly impacted 2-year overall survival (94% complete response on posttreatment PET/ CT vs 62.4% PET-IR, P