MRI-based low dose-rate brachytherapy experience in locally advanced cervical cancer patients initially treated by concomitant chemoradiotherapy

Purpose To retrospectively assess the physics contributions and the clinical outcome with preliminary 3D MRI-guided low dose-rate (LDR) intracavitary brachytherapy (BT) experience in locally advanced cervical cancel patients Patients and methods Eighty-four patients with primary locally advanced cervical carcinoma were analyzed The median tumoral cervical volume was 48.0 cc (range 1-468 cc) Twenty-four patients (53%) had histological and/or radiological pelvic involvement After pelvic +/- paraaortic concomitant chemoradiation, a LDR BT boost was delivered to a 3D MRI-based clinical target volume taking into account dose volume constraints for critical organs and optimization of target volume coverage Results With a median follow-up of 53 months (range 31-79 months), the 4 year overall survival and disease-lice survival rates were 57 (95%CI. 43-69) and 52% (95%CI, 40-64), respectively Adding EBRT and LDR using EQD2 model, the median D(100) and D(90) for the IR-CTV were 56 5 Gy(alpha/beta 10) (range 37-83 Gy(alpha/beta 10)) and 69 Gy(alpha/beta 10) (range 52-113 Gy(alpha/beta 10)). respectively For HR-CTV, the median D(100) and D(90) were 67 Gy(alpha/beta 10) (range 47-119 Gy(alpha/beta 10)) and 79 Gy(alpha/beta 10) (range 53-122 Gy(alpha/beta 10)). respectively Thirty-nine late complications were observed in 28 patients (33 3%). 13 bladder. 7 rectal. 5 small bowel, 4 urethral, 3 colic. 2 vaginal. 1 pelvic fibrosis, and 4 others Four grade 3 delayed complications were observed and no grade 4 complication occurred Conclusions Applying an individual treatment planning with 3D MRI-guided LDR brachytherapy appears to be feasible and efficient for patients with locally advanced cervical cancer in routine clinical practice. (C) 2010 Elsevier Ireland Ltd All rights reserved Radiotherapy and Oncology 96 (2010) 161-165