A Clinical Study of Pelvic Concurrent Chemoradiotherapy Combined with CT-guided Intracavitary Brachytherapy with Adaptive Simultaneous Dose Escalation for Locally Advanced Cervical Cancer

The standard treatment for locally advanced cervical cancer is cisplatin-based concurrent chemoradiotherapy with external beam radiotherapy (EBRT) and Brachytherapy (BT). overall treatment time (OTT) has been found to be an important predictor of treatment response. Some studies have shown that the acceleration of tumor cell regeneration during the extension of radiotherapy leads to poor local control. Prolonging the overall treatment time of cervical cancer radiotherapy for more than 8 weeks leads to an increase in pelvic local control failure. Therefore, shortening OTT has great potential benefits from both clinical efficacy and social benefits. Shortening OTT in radical cervical cancer radiotherapy includes hypofractionated EBRT and shortening the interval between BT and EBRT. However, further shortening OTT may lead to an increase in acute and late toxicity. Adaptive radiotherapy (ART) strategies systematically monitor variations in target and neighbouring structures to inform treatment-plan modification during radiotherapy. The application of image-guided adaptive brachytherapy (IGABT) has clearly demonstrated the advantages of this approach in the treatment of cervical cancer. Previous studies have shown that the implementation of IGABT can achieve personalized treatment, dose increase, improve clinical efficacy, reduce normal tissue toxicity and side effects, and strengthen international standardized quality control. In this study, online adaptive pelvic EBRT combined with IGABT based on uRT-linac was performed under online CT guidance. The aim of this study is to evaluate the safety and efficacy of pelvic concurrent chemoradiotherapy combined with CT-guided intracavitary brachytherapy with adaptive simultaneous dose escalation in locally advanced cervical cancer.