Impact of dosimetric parameters on local control for patients treated with three-dimensional pulsed dose-rate brachytherapy for cervical cancer

{PURPOSE: To investigate the impact of dose-volume histograms parameters on local control of three-dimensional (3D) image-based pulsed dose-rate brachytherapy (BT). METHODS AND MATERIALS: Within a French multicentric prospective study, the data of the 110 patients treated for cervical cancer with external beam radiotherapy followed by 3D image-based and optimized pulsed dose-rate BT were analyzed. Delineation procedures were performed on magnetic resonance imaging in a minority of cases and on CT for the majority of cases, adapted from the Gynaecological Groupe Europeen de Curietherapie-European Society for Therapeutic Radiology and Oncology recommendations. Optimization procedure was left to the discretion of the treating center. RESULTS: At 2 years, local control rate reached 78%. Dose to Point A, total reference air kerma, and intermediate-risk clinical target volume (IR-CTV) V-60 were predictive factors for local control (p = 0.001