Combined pretreatment with 18F-FDG PET/CT and Comet assay guides the concurrent chemoradiotherapy of locally advanced cervical cancer: study protocol for a randomized controlled trial

Abstract Background Cisplatin-based chemoradiation is the standard of care for patients with locally advanced cervical cancer. Nevertheless, an increasing number of radio-resistant tumors still recur. Methods and design Three hundred cervical cancer patients with FIGO stages IB2–IVA and no para-aortic lymphadenopathy (> 10 mm) will be enrolled. All patients will be randomly divided into four arms to receive either (1) intensity modulated radiation therapy (IMRT), (2) RapidArc, (3) positron emission tomography/computed tomography (PET/CT) with F-18 fluorodeoxyglucose (FDG), or (4) Comet assay-guided IMRT, PET/CT, and Comet assay-guided RapidArc. All patients will receive definitive radiotherapy consisting of external beam whole pelvic radiation therapy and high-dose rate intracavitary brachytherapy. Cisplatin 30 mg/m2 weekly will be administered concurrently for five courses. Two to four cycles of TP (Taxol 135 mg/m2, D1, and DDP 75 mg/m2, D1–3) sequential chemotherapy will be performed according to MRI or PET/CT after cisplatin-based chemoradiation. The primary outcome measure is progression-free survival, and the second outcome measures are overall survival and time to progression. Discussion RapidArc has an obvious advantage in improving the degree of target coverage, improving organs at risk, sparing healthy tissue, and significantly reducing the treatment time. FDG-PET/CT can increase the agreement between biopsies and delineated tumor volume and has the potential to positively impact the course of treatment. The Comet assay is attractive as a potential clinical test of tumor radiosensitivity. During radiotherapy, accurately defining disease areas is critical to avoid the unnecessary irradiation of normal tissue. Based on FDG-PET/CT and Comet assay, higher doses can be safely delivered to accurate tumor volumes, while the doses to the bladder and rectum are relatively low. Trial registration ClinicalTrials.gov Protocol Registration and Results System Receipt Release Date: May 21, 2017 – Retrospectively registered. NCT03163979