Bowel morbidity after prostate brachytherapy with Cesium-131 assessed by longitudinal EPIC survey.

Abstract

84 Background: Cesium-131 is a relatively new radioisotope for prostate brachytherapy (PB), with limited long- term data for toxicity profiles. Here we report our 1-year follow up for severity and time to resolution of bowel toxicity using Expanded Prostatic Cancer Index Composite (EPIC) scoring. METHODS Longitudinal prospective study of 186 patients with prostate cancer treated with Cesium-131 PB at our institution were followed by EPIC recordings. The mean prostatic volume was 41.3 cm3 and the mean prostate D90 and V100 were 105.7% and 92.4%, respectively. Patients completed surveys preoperative and at 2 weeks, 4 weeks, 3, 6, 9, and 12 months post-operatively. Outcomes were analyzed using student t-tests, with an EPIC score drop of > 10 points considered clinically significant. RESULTS For all patients (n=186), the mean EPIC bowel summary score at baseline was 90.1 ± 11.7 compared to 72.0 ± 21.8 [mean difference 19.0 ± 1.7, p<0.0001], 69.7 ± 21.4 (21.1 ± 2.0, p<0.0001), 87.0 ± 13.7 (3.4 ± 1.0, p = 0.001), 90.2 ± 10.1 (0.6 ± 1.0, p = 0.508), 89.8 ± 12.8 (1.4 ± 1.1, p = .216), and 88.5 ± 13.5 (2.6 ± 1.2, p = .031) at 2 weeks, 4 weeks, 3, 6, 9, and 12 months, respectively. For patients treated with PB alone (n=128), the mean EPIC bowel summary score at baseline was 91.6 ± 10.3 compared to 70.7 ± 23.2 (20.9 ± 2.1, p<0.0001), 66.1 ± 22.1 (25.3 ± 2.6, p<0.0001), 86.7 ± 13.8 (4.9 ± 1.2, p<0.0001), 91.4 ± 8.3 (0.8 ± 0.9, p = 0.396), 91.9 ± 10.8 (0.8 ± 1.3, p = 0.545), and 91.6 ± 10.5 (1.4 ± 1.3, p = 0.266), at 2 weeks, 4 weeks, 3, 6,9, and 12 months, respectively. For patients treated with external beam radiation therapy (EBRT) + PB (n=58), the mean EPIC bowel summary score at baseline was 89.6 ± 14.2 compared to 74.7 ± 18.6 (14.9 ± 2.6, p<0.0001), 77.2 ± 17.8 (12.3 ± 2.5, p<0.0001), 87.5 ± 13.7 (0.4 ± 1.8, p = 0.823), 87.9 ± 12.9 (0.3 ± 2.2, p = 0.884), 85.8 ± 15.3 (2.6 ± 2.2, p = 0.243), and 82.9 ± 16.1 (4.8 ± 2.5, p = 0.060) at 2 weeks, 4 weeks, 3, 6, 9, 12 months, respectively. CONCLUSIONS For men undergoing PB with Cesium-131 both as monotherapy and in conjunction with EBRT, bowel symptoms returned to clinical baseline within 3 months and statistical baseline within 6 months. These results remained non-significant relative to pre-operative values up to 1-year post-PB. No significant financial relationships to disclose.

Cite this paper

@article{Beriwal2011BowelMA, title={Bowel morbidity after prostate brachytherapy with Cesium-131 assessed by longitudinal EPIC survey.}, author={Sushi Beriwal and Ryan Smith and John A Vargo and Ronald M. Benoit}, journal={Journal of clinical oncology : official journal of the American Society of Clinical Oncology}, year={2011}, volume={29 7_suppl}, pages={84} }