Procedures
tumor
UTERINE CERVIX, BLOOD, TUMOR, VAGINA
Nivolumab was administered intravenously at the initial flat dose level of 240 mg q2w with concurrent CRT and maintained for 6 months after CRT completion, corresponding to a total of 13 cycles. Cisplatin was administered intravenously at 40 mg/m² every week, starting on day one of radiotherapy for a total of five cycles. Patients were treated with intensity-modulated radiation therapy technique, using linear accelerators. A dose of 45 gray (Gy) in 25 fractions was delivered to the gross tumor volume with a 2-cm margin, the vagina, the uterine cervix and corpus, the obturator nodes, the internal-external iliac nodes, the common iliac nodes, and the presacral nodes. The para-aortic area and common iliac nodes could also be treated in case of tumor involvement. Simultaneous integrated boost could be delivered to pathological lymph nodes to the total dose of 54 to 57.5 Gy in 25 fractions. Image-guided pulse-dose-rate brachytherapy was delivered on week 7 or 8; brachytherapy target volumes were determined according to the GYN GEC-ESTRO guidelines (13) to ensure homogeneity and reproducibility between the different centers. A total dose of 85 Gy was planned to be delivered to 90% of the high-risk volume and a dose of 60 Gy was planned to be delivered to 98% of the intermediate-risk volume.Patients were evaluated every week during CRT, every 2 weeks after CRT completion while undergoing nivolumab maintenance administration, and every 12 weeks thereafter. Blood samples were collected at baseline and during treatment. A tumor biopsy was performed at baseline only. Radiological assessment was performed at baseline, at brachytherapy initiation (week 7–8), at week 14–16, at week 25, and every 6 months thereafter by both pelvic MRI (T2- and T1-weighted images with gadolinium-chelates enhancement, and diffusion-weighted sequences) and 18F-fluorodeoxyglucose (