OC-40 IMAGE GUIDED BRACHYTHERAPY ENDS THE DEBATE OF SYSTEMATIC RADICAL HYSTERECTOMY IN LOCALLY ADVANCED CERVICAL CANCER

Abstract

Purpose/Objective: To evaluate the outcomes of 3D image guided brachytherapy (IGABT) after concomitant chemoradiation (CCT) in locally advanced cervical cancer. Materials and Methods: As part of the retro-EMBRACE revisory group, clinical data from patients treated at Institut Gustave-Roussy from 2004 to 2009 with curative intent IGABT after CCT were reviewed. Patients received pelvic +/para-aortic CCT (45-50.4 Gy) followed by MRI or CT guided pulsed dose rate BT. BT was performed according to GEC-ESTRO guidelines. Additional nodal or parametrial EBRT boosts were performed when indicated. In a first period, stage I or II patients systematically underwent radical hysterectomy or were offered a randomized study comparing hysterectomy versus observation in case of complete remission. Following the results of this trial, hysterectomy was limited to salvage treatment. Results: Of 163 patients identified, 27% had stage 1B, 6% IIA, 51% IIB, 3% IIIA, 9% IIIB and 3% IVA. At diagnosis, median tumour volume was 55 cm 3 (3-269). Squamous cell carcinoma was the commonest histological subtype (87%). Nodal involvement was noticed in 37% of the patients; among them, 15% had para aortic involvement. Ninety percents received concomitant chemotherapy and 18% received pelvic plus para-aortic EBRT. BT was based on MRI in 88% of the cases and on CT for the remaining 12%. Vaginal personalized mould was used in the majority of applications (95%), with an intracavitary technique in all cases except two. The doses delivered (EBRT + BT, in EqD2) were 67.1+/-6.4 Gy (α/β=10) to 90% of the IR-CTV, 78.1+/-9.6 Gy (α/β=10) to 90% of the HR-CTV. The D2cc for the bladder, rectum and sigmoid were 67.8+/-6.7 Gy, 58.8+/-5.9 Gy and 58.3 Gy+/-5.7 (α/β=3) respectively. Sixty-one patients (37%) underwent a radical hysterectomy. Macroscopic residual disease was found in 13 cases. With a median follow-up of 36 months (5-79), 45 patients had relapsed. Twelve local relapses were reported (5 central and 7 lateral +/central), of which 4 were isolated. There were 22 nodal failures (10 pelvic and 12 para-aortic) and 28 metastatic relapses. At the time of failure, 70.4% of the patients had distant metastasis, and this was isolated in more than a half. The 3 year OS and DFS were 84% and 73% respectively. Local control was 92% and pelvic control was 86%. Local control decreased in relation to the initial tumour width: 97% for <5cm (n=74), 91 for 5-6cm (n=50) and 81% for ≥6cm(n=39), p=0.036. According to the Common Toxicity Criteria 3.0, 7.4% of patients experienced late grade 3/4 toxicity. Seventy-five percent (9/12) of those with a grade 3/4 toxicity had undergone post-radiation radical surgery. Conclusions: IGABT combined with CCT provides excellent locoregional control rates with low treatment related morbidity, justifying the elimination of radical hysterectomy in the absence of obvious local failure. Distant metastasis remains an important site of first relapse and may warrant more aggressive systemic treatment.