Introduction/Background After the published guidelinesof Group Européen de Curiethérapie and European Society for Radiotherapy andOncology (GEC-ESTRO) for tridimensional image-guided brachytherapy, many cancercenters have started abandoning the bidimensional conventional brachytherapy(2D-BT). The purpose of this study was to analyze the transition from 2D-BT totridimensional computed tomography-guided brachytherapy (CT-BT) and its effectson target and organs at risk in cervical cancer patients treated in ourinstitution.

Methodology We performed a retrospectiveanalysis of 308 patients diagnosed with cervical cancer between 2016 and 2018.All patients were treated with primary chemoradiation, followed by CT-BT. Foreach patient we used a tandem-ring applicator and retrospectively realized one2D-BT plan with dose prescribed in International Commission on Radiation Unitsand Measurements (ICRU) point A and equal dwell times and a second plan withdose prescribed to the high-risk clinical target volume (HR-CTV) and differentdwell times.

Results When prescribed to ICRUreference points, the mean dose to point A was 99.88% of the prescription dose(PD), the mean ICRU bladder and rectum point dose was 102.38% and 100.79% ofPD, respectively. When prescribed to HR-CTV, the mean dose to irradiated volumewas 96.6% of the PD, mean D2cc for bladder and rectum was 86.76% and 65.58% ofPD, respectively. Mean volume of 100% dose was 106.5cc vs 78.25cc whenprescribing to point A vs HR-CTV.

Conclusion The study showed a reduction ofthe irradiated volume by 23.3% when the prescription of dose was done to HR-CTVcompared to point A, the D2cc for bladder and rectum were also lowered. Inconclusion, the old and never-ending love story of 2D-BT and CT-BT has to cometo an end in our institution, in order for the tridimensional image-guidedbrachytherapy techniques to write their own story and for cervical cancer tostop getting the principal role.

Disclosure Nothing to disclose.