Relación entre variabilidad del índice de resistencia de arterias uterinas y sobrevida en pacientes de cáncer de cérvix sometidas a braquiterapia de baja tasa de dosis.

Background: The aim of this sudy was to determine if an increased variation between the RI ( resistance index) of uterine artery pre and post LDR ( low dose rate) gynecologyc brachytherapy, could be a good prognosis indicator . Methods: Observational prospective study, participants included 23 patients which were treated in the Radiotherapy service, between October 2012 and July 2013; a Doppler Color Ultrasound was made aiming at the measurement of the RI of both uterine arteries, before and after aplication of LDR brachytherapy. The variability of each uterine artery RI was determined, and normal distribution curves were built; a group of patients which values were major or equal to 2 SD ( standard deviations). All patients were followed for a period of time up to 24 months. The endpoint was OS ( overall survival). Results: Mean OS was 15.69 months. 5 patients ( 21.74%), presented disease persistence/progression. At the end of the follow up period, OS percentage was 83% (n=19). In the group of patients with variability of RI of the uterine artery equal to or more than 2SD, OS was 100% ( p=0,0411 in univariable analysis, p=0,06 in multivariable analysis). Conclusion: In the follow up to 15,69 months, the group with greater variability of RI of uterine arteries had an OS of 100%, with statistical significance in univariable analysis, showing a trend towards statistical signification in multivariable analysis. We need to do more studies to better identification of this relation. [ABSTRACT FROM AUTHOR]