Vaginal dilator use more than 9 months is a main prognostic factor for reducing G2-late vaginal complications in 3D-vaginal-cuff brachytherapy (interventional radiotherapy)?

PurposeAnalyse the impact of different prognostic factors on G2-late vaginal complications after vaginal brachytherapy (VBT) +/- external beam radiotherapy (EBRT) in postoperative endometrial cancer (PEC).MethodsOne hundred and twenty-six PEC patients treated with VBT +/- EBRT were retrospectively analysed considering age, body mass index, applicator diameter, clinical target volume (CTV), use of dilators, chemotherapy and EQD2((alpha/beta=3)) at the most exposed 2 cm(3) of the CTV as prognostic factors for vaginal complications. Late vaginal complications were evaluated using objective LENT-SOMA criteria. Statistics: descriptive analysis, Chi-square, Fisher and Student tests were applied. Univariate and multivariate analyses were performed with the Baptista-Pike exact method and multiple logistic regression.ResultsMean age was 65 years (SD +/- 10), and median follow-up was 66 months (8-104). 19/126 patients (15%) showed G2-late vaginal complications, and 107/126 (85%) G0-G1. Univariate analysis showed: CTV <= 9 cm(3) (p = 0.036), use of dilators < 9 months (p = 0.015), and total >= 68 Gy EQD2 received by 2 cm(3) of CTV (p = 0.039) were associated with G2-late vaginal toxicity. Multivariate analysis showed the use of dilators < 9 months as an independent prognostic factor for G2-late vaginal toxicity (p = 0.043, OR 8.59, CI 1.59-159.9).ConclusionThe use of dilators < 9 months in VBT +/- EBRT for PEC was an independent prognostic factor for G2-late vaginal toxicity. The use of vaginal dilators >= 9 months requires further analysis in studies evaluating late vaginal toxicity.