Department of Urology, Keio University School of Medicine, Tokyo, Japan.
Department of Urology, St. Marianna University School of Medicine, Kanagawa, Japan.
Int J Urol. 2020 Dec;27(12):1087-1093. doi: 10.1111/iju.14358. Epub 2020 Sep 6.
To investigate the relationship between radiation doses in prostate brachytherapy and deterioration of erectile function in patients with localized prostate cancer.
A longitudinal survey study was carried out among 261 prostate cancer patients who received prostate brachytherapy. A total of 48 patients were potent at baseline and they did not receive any supplemental therapy preoperatively. Dosimetry parameters of the whole prostate gland, prostate apex, urethra and rectum were collected using the VariSeed 8.0 treatment planning system (Varian Medical Systems, Palo Alto, CA, USA). We carried out a logistic regression analysis to clarify the relationship between radiation doses and erectile function deterioration, which was assessed using the International Index of Erectile Function-15 questionnaire.
The median patient age was 66 years (range 53-70 years) with a median follow-up time of 44 months (36-71 months). The mean total International Index of Erectile Function-15 score decreased from 49.9 at baseline to 34.7 after 12 months (P < 0.001), but gradually plateaued within 36 months. Erectile function deterioration was noted in 32 (66.7%) patients 36 months after prostate brachytherapy. In an analysis of risk factors for erectile function deterioration after prostate brachytherapy, age ≥70 years (P = 0.029), prostate V100 ≥95% (P = 0.024), apex V100 ≥95% (P = 0.024), apex V150 ≥70% (P = 0.009) and apex D90 ≥150 Gy (P = 0.011) correlated with erectile function deterioration. A multivariate analysis identified an age of ≥70 years (odds ratio 7.91, P = 0.024) and apex V150 ≥70% (odds ratio 7.75, P = 0.007) as independent risk factors for erectile function deterioration after prostate brachytherapy.
An excessive radiation dose, particularly to the prostate apex area, and an advanced age might have a negative impact on the preservation of potency after prostate brachytherapy.
研究局部前列腺癌患者前列腺近距离放射治疗中放射剂量与勃起功能恶化的关系。
对 261 例接受前列腺近距离放射治疗的前列腺癌患者进行了纵向调查研究。共有 48 例患者在基线时具有勃起功能，且术前未接受任何补充治疗。使用 VariSeed 8.0 治疗计划系统（美国加利福尼亚州帕洛阿尔托市的 Varian Medical Systems）收集整个前列腺、前列腺尖部、尿道和直肠的剂量学参数。我们进行了逻辑回归分析，以明确放射剂量与勃起功能恶化的关系，勃起功能恶化通过国际勃起功能指数-15 问卷进行评估。
患者中位年龄为 66 岁（53-70 岁），中位随访时间为 44 个月（36-71 个月）。国际勃起功能指数-15 总评分从基线时的 49.9 分降至 12 个月后的 34.7 分（P<0.001），但在 36 个月内逐渐趋于平稳。前列腺近距离放射治疗后 36 个月时，32 例（66.7%）患者出现勃起功能恶化。在分析前列腺近距离放射治疗后勃起功能恶化的危险因素时，年龄≥70 岁（P=0.029）、前列腺 V100≥95%（P=0.024）、尖部 V100≥95%（P=0.024）、尖部 V150≥70%（P=0.009）和尖部 D90≥150 Gy（P=0.011）与勃起功能恶化相关。多因素分析确定年龄≥70 岁（优势比 7.91，P=0.024）和尖部 V150≥70%（优势比 7.75，P=0.007）是前列腺近距离放射治疗后勃起功能恶化的独立危险因素。
前列腺尖部区域的放射剂量过高以及高龄可能对前列腺近距离放射治疗后的勃起功能保留产生负面影响。
