Sexual (dys)function after radiotherapy for prostate cancer: a review.
ABSTRACT Prostate cancer has become the most common nonskin malignant neoplasm in older men in Western countries. As treatment efficacy has improved, issues related to posttherapy quality of life and sexual functioning have become more important.
We discuss the various methods used to evaluate erectile and sexual dysfunction and the definition of potency. The etiologies of erectile dysfunction after external beam radiotherapy and brachytherapy for prostate cancer are also reviewed. The literature is summarized, and comparative studies of radiation and surgery are surveyed briefly.
Rates of erectile dysfunction vary from 6 to 84% after external beam radiotherapy and from 0 to 51% after brachytherapy. In most of the studies, the analysis is retrospective, the definition of erectile dysfunction is not clear, only one question about sexual functioning is asked, and nonvalidated instruments are used. The etiology of erectile dysfunction after radiation for prostate cancer is not completely understood.
Because erectile function is only one component of sexual function, it is necessary to assess sexual desire, satisfaction, frequency of intercourse, and other such factors when evaluating the effects of therapy. Patients should be offered sexual counseling and informed about the availability of effective treatments for erectile dysfunction, such as sildenafil, intracavernosal injection, and vacuum devices.
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ABSTRACT: The radiation doses received by erectile tissue may contribute to erectile dysfunction after treatment of prostate cancer. This is the first description of the ability to limit the dose received by the penile bulb (PB) and corporal bodies (CB) using intensity-modulated radiotherapy (IMRT). Twenty-three patients with palpation Stage T1c-T2bN0M0 prostate cancer received IMRT alone. The dose prescribed to the planning target volume was 74-78 Gy. All patients underwent CT and MRI simulation to define the target and normal structures. Three plans with identical beam arrangements and energy were generated for each patient, with varying dose constraints for the PB and CB: no dose constraint, intermediate-dose constraint (20 Gy and 15 Gy, respectively) and low-dose constraint (15 Gy and 7 Gy, respectively). All plans were normalized, such that 95% of the planning target volume received at least 100% of the prescribed dose. For each plan, the ability to meet prostate dose homogeneity criteria (PHC; prostate maximal dose </=120% prescribed dose) and rectal tolerance dose-volume histogram criteria (RTC; </=35% and </=17% of rectal volume received 40 Gy and 65 Gy, respectively) was determined. The D(90), V(50), and V(75) were determined for both PB and the CB, where D(i) was the dose received by i% of the target volume and V(i) was the target volume receiving i% of the prescribed dose. The median PB D(90), V(50), and V(75) for the plans with no dose, intermediate-dose, and low-dose constraints was 20.8 Gy, 33.8%, and 9.9%; 8.0 Gy, 1.7%, and 0%; and 7.1 Gy, 0.1%, and 0%, respectively. The median CB D(90), V(50), and V(75) for plans with no dose, intermediate-dose, and low-dose constraints was 10.2 Gy, 3.8%, and 0%; 6.0 Gy, 0%, and 0%; and 4.9 Gy, 0%, and 0%, respectively. Overall differences in the D(90), V(50), and V(75) among the groups were significant for both the PB and the CB (p <0.0001). All plans with no dose constraint met the PHC and RTC. Twenty plans with an intermediate-dose constraint met the PHC and 21 met the RTC. Eighteen plans with a low-dose constraint met the PHC and 19 met the RTC. No statistically significant difference was found in the number of beam segments for the three groups (median of 51, 55, and 53; p = 0.8). In the vast majority of cases, it is possible to limit the dose to erectile tissue with IMRT, usually by >/=50% without significantly compromising the PHC, RTC, or treatment duration. A Phase III randomized trial has been designed to test the clinical significance of the erectile tissue-sparing technique described here.International Journal of Radiation OncologyBiologyPhysics 04/2004; 58(3):743-9. · 4.52 Impact Factor
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ABSTRACT: INTRODUCTION: Vascular comorbidities (VC) (hypertension, diabetes, and hyperlipidemia) are known factors related to erectile dysfunction (ED) in men. However, no data are yet available for the effects of VC on ED incidence after prostate cancer radiotherapy (XRT). AIM: To investigate the influence of VC on post-XRT ED incidence and to further characterize ED incidence by racial groups. MAIN OUTCOME MEASURES: ED incidence. METHODS: We reviewed 732 charts of patients (267 Caucasian and 465 African American [AA]) who received prostate XRT (external beam radiotherapy and/or brachytherapy) with or without hormone therapy between 1999 and 2010. The number of pre-XRT VC (0, 1, 2, or 3) was determined by medical history and medication list. ED (defined by use of erectile aids or by documentation of moderate or high sexual dysfunction on patient history) was determined pre-XRT as well as 1, 2, and 4 years post-XRT. RESULTS: ED incidence progressively increased from 22% pre-XRT to 58% 4 years post-XRT (P < 0.01). Additionally, ED incidence significantly increased with number of VC-4-year incidence between patients with 1 vs. 0 (P = 0.02), 2 vs. 0 (P < 0.01), 3 vs. 0 (P < 0.01), 3 vs. 1 (P < 0.01), and 3 vs. 2 (P = 0.04) VC (2 vs. 1 VC was nonsignificant). Compared with the Caucasian patients, ED incidences were slightly higher for the AA group with 0, 1, 2, and 3 comorbidities at 4 years follow-up (but statistically nonsignificant). CONCLUSIONS: The number of VCs have a significant effect on development of post-XRT ED. Pre- and post-XRT ED appear to be independent of race when number of VCs are considered. Our results can be used to guide physicians in counseling patients on the incidence of ED by number of VC and as preliminary data for prospective efforts aimed at reducing post-XRT ED. Wang Y, Liu T, Rossi PJ, Watkins-Bruner D, Hsiao W, Cooper S, Yang X, and Jani AB. Influence of vascular comorbidities and race on erectile dysfunction after prostate cancer radiotherapy. J Sex Med **;**:**-**.Journal of Sexual Medicine 06/2013; · 3.51 Impact Factor
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ABSTRACT: Within a multicenter study (DUE-01) focused on the search of predictors of erectile dysfunction and urinary toxicity after radiotherapy for prostate cancer, a dummy run exercise on penile bulb (PB) contouring on computed tomography (CT) images was carried out. The aim of this study was to quantitatively assess interobserver contouring variability by the application of the generalized DICE index. Fifteen physicians from different Institutes drew the PB on CT images of 10 patients. The spread of DICE values was used to objectively select those observers who significantly disagreed with the others. The analyses were performed with a dedicated module in the VODCA software package. DICE values were found to significantly change among observers and patients. The mean DICE value was 0.67, ranging between 0.43 and 0.80. The statistics of DICE coefficients identified 4 of 15 observers who systematically showed a value below the average (p value range, 0.013 - 0.059): Mean DICE values were 0.62 for the 4 "bad" observers compared to 0.69 of the 11 "good" observers. For all bad observers, the main cause of the disagreement was identified. Average DICE values were significantly worse from the average in 2 of 10 patients (0.60 vs. 0.70, p < 0.05) because of the limited visibility of the PB. Excluding the bad observers and the "bad" patients," the mean DICE value increased from 0.67 to 0.70; interobserver variability, expressed in terms of standard deviation of DICE spread, was also reduced. The obtained values of DICE around 0.7 shows an acceptable agreement, considered the small dimension of the PB. Additional strategies to improve this agreement are under consideration and include an additional tutorial of the so-called bad observers with a recontouring procedure, or the recontouring by a single observer of the PB for all patients included in the DUE-01 study.International journal of radiation oncology, biology, physics 03/2012; 84(3):841-6. · 4.59 Impact Factor