Bladder (ICRU) dose point does not predict urinary acute toxicity in adjuvant isolated vaginal vault high-dose-rate brachytherapy for intermediate-risk endometrial cancer

Abstract

PurposeHigh-dose-rate brachytherapy (HDR-BT) alone is an adjuvant treatment option for stage I intermediaterisk endometrial cancer after complete surgical resection. The aim of this study was to determine the value of the dose reported to ICRU bladder point in predicting acute urinary toxicity. Oncologic results are also presented.Material and methodsOne hundred twenty-six patients were treated with postoperative HDR-BT 24 Gy (4 × 6 Gy) per ICRU guidelines for dose reporting. Cox analysis was used to identify variables that affected local control. The mean bladder point dose was examined for its ability to predict acute urinary toxicity.ResultsTwo patients (1.6%) developed grade 1 gastrointestinal toxicity and 12 patients (9.5%) developed grades 1-2 urinary toxicity. No grade 3 or greater toxicity was observed. The mean bladder point dose was 46.9% (11.256 Gy) and 49.8% (11.952 Gy) for the asymptomatic and symptomatic groups, respectively (p = 0.69). After a median follow-up of 36.8 months, the 3-year local failure and 5-year cancer-specific and overall survival rates were 2.1%, 100%, and 94.6%, respectively. No pelvic failure was seen in this cohort. Age over 60 years (p = 0.48), lymphatic invasion (p = 0.77), FIGO histological grade (p = 0.76), isthmus invasion (p = 0.68), and applicator type (cylinder × ovoid) (p = 0.82) did not significantly affect local control.ConclusionsIn this retrospective study, ICRU bladder point did not correlate with urinary toxicity. Four fractions of 6 Gy HDR-BT effected satisfactory local control, with acceptable urinary and gastrointestinal toxicity.

Volumetric (3D) bladder dose parameters are more reproducible than point (2D) dose parameters in vaginal vault high-dose-rate brachytherapy

“…Although the use of CT scan for dose calculation in VCB is attractive, no study has proven the superiority of volumetric data against classical ICRU points with regard to predicting urinary toxicity, necessitating a discussion of the cost-effectiveness of planning with tridimensional imaging in VCB compared with simple x-ray due to the minimal optimization of the applicators 13 14 15 , lack of clinical correspondence of the reported dose 16 and significant rise in procedure costs 7 .…”

“…Our group recently published a retrospective series on 126 patients who were treated with high-dose-rate VCB alone for intermediate-risk endometrial cancer with a 9.5% rate of grades 1 or 2 acute urinary toxicity and no case of grade 3 toxicity 16 . We did not find any differences in bladder ICRU point doses between the asymptomatic group and symptomatic group, with 11.256 Gy × 11.952 Gy ( p = 0.69), respectively.…”

“…We did not find any differences in bladder ICRU point doses between the asymptomatic group and symptomatic group, with 11.256 Gy × 11.952 Gy ( p = 0.69), respectively. Additionally, the use of a Foley catheter was deemed to be responsible for part of the acute toxicity reported, due to an inherent increased risk of urinary tract infection 7 16 . Despite the low rates of grades 3 and 4 urinary toxicity in the literature after VCB alone (<3%) 5 , the combination with EBRT could lead to serious complications, like bowel perforation and urethral strictures 1 .…”

Effects of vaginal cylinder position on dose distribution in patients with endometrial carcinoma in treatment of vaginal cuff brachytherapy

“…Therefore, it is important to consider all factors related to the dosimetry of critical organs and the target volume. Although numerous studies have investigated the effects of indication [ 4 , 9 ], treatment time [ 10 ], size [ 4 , 11 ], and style [ 12 ] of the cylinder, filling of the bladder and rectum [ 4 , 13 , 14 ], dose fractionation, and prescription [ 4 , 15 ], the impact of the cylinder position has received little study.…”

Acute and late vaginal toxicity after adjuvant high-dose-rate vaginal brachytherapy in patients with intermediate risk endometrial cancer: is local therapy with hyaluronic acid of clinical benefit?

“…High-dose-rate-vaginal BT can be considered as an adjuvant radiotherapy of choice in intermediate risk patients after surgical staging including pelvic ± aortic lymphadenectomy [11, 12, 13, 14, 15, 16]. However, acute and long-term side effects, such as thinning and increasing fragility of vaginal walls, atrophy, adhesions, fibrosis, and stenosis, have been reported also after HDR-vaginal BT, with occasional impairment of sexual life [8, 9, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23]. …”