1083 - Prospective Two-Year Progression-Free Survival and Toxicity after Daily Online Adaptive Radiotherapy for Cervical Cancer
Presenter(s)
G. Wang1, J. Yang2, J. Yan1, K. Hu1, and F. Zhng1; 1Department of Radiation Oncology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China, 2China National Academy of Educational Sciences (CNAES), Beijing, China
Purpose/Objective(s): Daily online adaptive radiotherapy (oART) accounts for inter-fraction anatomic variation in cervical cancer, but prospective long-term clinical and patient-reported outcomes remain limited. We evaluated two-year progression-free survival (PFS), patterns of failure, late physician-reported toxicity, and patient-reported outcomes (PROs) after daily oART.
Materials/Methods: In this prospective single-arm study, we enrolled postoperative adjuvant (n=17) and definitive (n=27) cervical cancer cohorts, all treated using a standardized daily iterative cone-beam CT (iCBCT)-guided online adaptive radiotherapy (oART) workflow. Postoperative patients received pelvic EBRT to 45.0 or 50.4 Gy in 1.8-Gy fractions, followed by CT-guided high-dose-rate intracavitary brachytherapy to 10 Gy in 2 fractions. Definitive patients received EBRT to 50.4 Gy in 28 fractions with concurrent weekly chemotherapy, with a simultaneous nodal boost to 60.2 Gy in 2.15-Gy fractions when indicated, followed by brachytherapy per protocol. A uniform 10 mm margin was used to cover more variable uterus (PTV-U), and a uniform 5 mm margin was used for other PTV. PFS was measured from radiotherapy start to first progression or recurrence; patients without progression were censored at last follow-up. Kaplan-Meier methods estimated two-year PFS. Distant failure sites were abstracted from recurrence documentation. Late physician-reported toxicities were graded using CTCAE v4.0 (late defined as >90 days after RT) and summarized as patient counts. PROs were scored using EORTC QLQ-C30 (0 to 100) and summarized for selected symptom and function domains.
Results: At last follow-up, all patients were alive. Median follow-up was 34.0 months overall (39.9 months postoperative; 31.5 months definitive). Two-year PFS was 93.8% in the postoperative cohort and 87.8% in the definitive cohort. Four recurrences occurred; supraclavicular lymph nodes represented the most common distant metastatic site. Late physician-reported toxicities occurred in 2 postoperative patients and 10 definitive patients, predominantly gastrointestinal and genitourinary events. At follow-up, PRO symptom burden was low (fatigue 5.9 vs 7.8; pain 1.0 vs 3.1 for postoperative vs definitive), with high function (physical 94.9 vs 96.8; role 96.1 vs 100.0) and global health/quality of life of 88.2 vs 87.0. In the definitive cohort, treatment-phase PRO elevations largely resolved by follow-up.
Conclusion: In this prospective trials, daily iCBCT-guided oART achieved favorable two-year PFS with limited late toxicity and strong patient-reported recovery in both postoperative and definitive cervical cancer cohorts, supporting broader adoption of daily oART in routine practice.