Sexual Function After Three-Dimensional Conformal Radiotherapy for Prostate Cancer: Results From a Dose-Escalation Trial

Global research trends on the links between prostate cancer and erectile dysfunction between 2003 and 2023: A bibliometrics and visualized study

Background

The incidence of prostate cancer (PC) has increased in recent years. Erectile dysfunction (ED) after prostate cancer treatment has aroused extensive attention. Bibliometric analysis was designed to investigate a systematic understanding of developments between PC and ED during the past 20 years.

Methods

Literatures on PC and ED were retrieved from the Web of Science Core Collection database (WoSCC). By using the VOS viewer and CiteSpace software to analysis the metrics of bibliometric literature, such as number of articles, journals, countries, institutions, authors, keywords and associated information. The number of publications per year was statistically analysed and plotted thorough Microsoft Office. In addition, Pajek software was used to adjust the visual map.

Results

A total of 2332 screened articles were included in the analysis. The Journal of Sexual Medicine, ranking first among the analysed journals, published 235 articles. The United States and Canada were leaders in PC and ED research. There is a need to strengthen inter-agency cooperation in this area of research on a global scale. Mulhall JP, as the most prolific author in this area of research, published 80 articles. And Rosen RC was the author with the most co-citated (693 co-citated). The main research focus on the prevention, treatment and management of ED after PC treatment in this field through the keyword analysis.

Conclusions

Research on PC and ED is expected to expand further worldwide. We found ED, as new sustainable treatment modalities, scientific postoperative management and psychological interventions for patients, may become the research hotspots and should be closely concerned in this study.

Sexual satisfaction in prostate cancer: a multi-group comparison study of treated patients, patients under active surveillance, patients with negative biopsy, and controls

PURPOSE

Erectile function changes after prostate cancer (PCa) treatment are well documented, but less understood is the relative impact of prostate biopsy and active surveillance on sexual well-being. It is unknown whether potential negative impacts are exclusive to patients who have been treated for PCa, or whether the diagnosis itself or the experience of biopsy may also impact sexual well-being. Sexual satisfaction is an important yet understudied indicator of sexual well-being in this population. This study examines sexual satisfaction and its predictors across several comparison groups to explore relative impact.

METHODS

At baseline and 12 months, questionnaire data was collected in four samples: (1) following PCa treatment, (2) active surveillance, (3) negative prostate biopsy result, and (4) controls receiving no biopsy or treatment. Predictors assessed included group, erectile function, communication style, and partner involvement.

RESULTS

Sexual satisfaction declined in the active treatment group, no changes were observed in active surveillance or non-PCa control, and improvements were observed in the biopsy group. Predictors of sexual satisfaction over and above erectile function included restrictive communication (i.e. protective buffering) and perceived partner involvement. For higher levels of erectile function, a higher perceived degree of partner involvement was protective of sexual satisfaction.

CONCLUSION

Sexual satisfaction is an important indicator of sexual well-being and is negatively impacted following PCa treatment, but not active surveillance or prostate biopsy.

IMPLICATIONS FOR CANCER SURVIVORS

Communication and partner involvement are potentially modifiable factors to be considered for intervention and may promote sexual satisfaction following PCa treatment. Patients experiencing negative biopsy, who note lower sexual satisfaction may experience improved satisfaction with time, and those under active surveillance who worry about sexual satisfaction may find reassurance from these results.

Nanotechnology as a tool to advance research and treatment of non-oncologic urogenital diseases

Nanotechnology represents an expanding area of research and innovation in almost every field of science, including Medicine, where nanomaterial-based products have been developed for diagnostic and therapeutic applications. Because of their small, nanoscale size, these materials exhibit unique physical and chemical properties that differ from those of each component when considered in bulk. In Nanomedicine, there is an increasing interest in harnessing these unique properties to engineer nanocarriers for the delivery of therapeutic agents. Nano-based drug delivery platforms have many advantages over conventional drug administration routes as this technology allows for local and transdermal applications of therapeutics that can bypass the first-pass metabolism, improves drug efficacy through encapsulation of hydrophobic drugs, and allows for a sustained and controlled release of encapsulated agents. In Urology, nano-based drug delivery platforms have been extensively investigated and implemented for cancer treatment. However, there is also great potential for use of nanotechnology to treat non-oncologic urogenital diseases. We provide an update on research that is paving the way for clinical translation of nanotechnology in the areas of erectile dysfunction (ED), overactive bladder (OAB), interstitial cystitis/bladder pain syndrome (IC/BPS), and catheter-associated urinary tract infections (CAUTIs). Overall, preclinical and clinical studies have proven the utility of nanomaterials both as vehicles for transdermal and intravesical delivery of therapeutic agents and for urinary catheter formulation with antimicrobial agents to treat non-oncologic urogenital diseases. Although clinical translation will be dependent on overcoming regulatory challenges, it is inevitable before there is universal adoption of this technology to treat non-oncologic urogenital diseases.

A flavonoid derivative of icariside II (YS-10) improves erectile dysfunction in radiation-injured rats via oxidative stress pathway

Background

We explored the preventive effect and mechanism of YS-10, a novel synthesized flavonoid derivative based on the structure of icariside II (ICA II), on a rat model of radiation-induced erectile-dysfunction (Ri-ED).

Methods

Eighteen 10-week-old male Sprague-Dawley (SD) rats were randomly divided into 3 groups. Six rats were used as the control group (Control), and the remaining 12 were given a single X-ray irradiation of 20 Gy in the prostate and then randomly divided into the radiation injury group (Ri-ED group) and YS-10 treatment group (Ri-ED+YS-10, 2.5 mg/kg/day). After 4 weeks of drug administration and a 2-week drug washout period in the YS-10 treatment group, the erectile function of the animals was evaluated, and the tissues were collected for histopathological analysis and detection of oxidative stress indicators.

Results

After radiation injury, the ratio of maximum intracavernosal pressure (ICP) to mean arterial pressure (MAP), the number of neuronal nitric oxide synthase (n-NOS) positive nerve fibers in the penis cavernosa, endothelial cell content, and n-NOS and endothelial nitric oxide synthase (e-NOS) proteins in the Ri-ED group were significantly lower than those in control group. Compared with the control group, the Ri-ED group had lower superoxide dismutase (SOD) levels and higher malondialdehyde (MDA) levels. Compared with the Ri-ED group, the YS-10 group had a significant increase in the ratio of ICP/MAP in the corpus cavernosum (0.59±0.06 vs. 0.43±0.06, P<0.01), the number of n-NOS positive nerve fibers, and the content of endothelial cells. The protein content of n-NOS and e-NOS in the corpus cavernosum increased and could significantly reduce the level of MDA (2.67±0.27 vs. 3.25±0.21, P<0.05).

Conclusions

As a novel ICA II derivative, YS-10 could significantly improve the erectile dysfunction and pathological damage in rats caused by radiation injury, and its mechanism may be related to the improvement of radiation-induced oxidative stress.

Evaluation of set-up errors and estimation of set-up margin during external beam radiation therapy of prostate cancer using electronic portal imaging device (EPID)

Aim:

In radiation therapy, accurate dose distribution in target volume requires accurate treatment setup. The set-up errors are unwanted and inherent in the treatment process. By achieving these errors, a set-up margin (SM) of clinical target volume (CTV) to planning target volume (PTV) can be determined. In the current study, systematic and random set-up errors that occurred during prostate cancer radiotherapy were measured by an electronic portal imaging device (EPID). The obtained values were used to propose the optimum CTV-to-PTV margin in prostate cancer radiotherapy.

Materials and methods:

A total of 21 patients with prostate cancer treated with external beam radiation therapy (EBRT) participated in this study. A total of 280 portal images were acquired during 12 months. Gross, population systematic (Σ) and random (σ) errors were obtained based on the portal images in Anterior–Posterior (AP), Medio-Lateral (ML) and Superior–Inferior (SI) directions. The SM of CTV to PTV were then calculated and compared by using the formulas presented by the International Commission on Radiation Units and Measurements (ICRU) 62, Stroom and Heijmen and Van Herk et al.

Results:

The findings showed that the population systematic errors during prostate cancer radiotherapy in AP, ML and SI directions were 1·40, 1·95 and 1·94 mm, respectively. The population random errors in AP, ML and SI directions were 2·09, 1·85 and 2·29 mm, respectively. The SM of CTV to PTV calculated in accordance with the formula of ICRU 62 in AP, ML and SI directions were 2·51, 2·68 and 3·00 mm, respectively. And according to Stroom and Heijmen, formula were 4·23, 5·19 and 5·48 mm, respectively. And Van Herk et al. formula were 4·96, 6·17 and 6·45 mm, respectively.

Findings:

The SM of CTV to PTV in all directions, based on the formulas of ICRU 62, Stroom and Heijmen and van Herk et al., were equal to 2·73, 4·98 and 5·86 mm, respectively; these values were obtained by averaging the margins in all directions.

Erectile dysfunction and cancer: current perspective

Erectile dysfunction (ED) is one of the major but underreported concerns in cancer patients and survivors. It can lead to depression, lack of intimacy between the couple, and impaired quality of life. The causes of erectile dysfunction are psychological distress and endocrinal dysfunction caused by cancer itself or side effect of anticancer treatment like surgery, radiotherapy, chemotherapy and hormonal therapy. The degree of ED depends on age, pre-cancer or pre-treatment potency level, comorbidities, type of cancer and its treatment. Treatment options available for ED are various pharmacotherapies, mechanical devices, penile implants, or reconstructive surgeries. A complete evaluation of sexual functioning should be done prior to starting anticancer therapy. Management should be individualized and couple counseling should be an integral part of the anticancer treatment.

Risk of erectile dysfunction after modern radiotherapy for intact prostate cancer

BACKGROUND

Erectile dysfunction (ED) is a prevalent side effect of prostate cancer treatment. We hypothesized that the previously reported rates of ED may have improved with the advent of modern technology. The purpose of this project was to evaluate modern external beam radiotherapy and brachytherapy techniques to determine the incidence of radiotherapy (RT) induced ED.

METHODS

A systematic review of the literature published between January 2002 and December 2018 was performed to obtain patient reported rates of ED after definitive external beam radiotherapy, ultrafractionated stereotactic radiotherapy, and brachytherapy (BT) to the prostate in men who were potent prior to RT. Univariate and multivariate analyses of radiation dose, treatment strategy, and length of follow-up were analyzed to ascertain their relationship with RT-induced ED.

RESULTS

Of 890 articles reviewed, 24 met inclusion criteria, providing data from 2714 patients. Diminished erectile function status post RT was common and similar across all studies. The median increase in men reporting ED was 17%, 26%, 23%, and 23%, 3DCRT, IMRT, low dose rate BT, and SBRT, respectively, at 2-year median follow-up.

CONCLUSION

ED is a common side effect of RT. Risk of post-RT ED is similar for both LDR brachytherapy and external beam RT with advanced prostate targeting and penile-bulb sparing techniques utilized in modern RT techniques.

RhoA/ROCK pathway inhibitor ameliorates erectile dysfunction induced by radiation therapy in rats

OBJECTIVES

Prostate cancer (PCa) treatment with radiation therapy (RT) has an excellent cure rate. However, Radiation-induced Erectile Dysfunction (RiED) is a common and irreversible toxicity impacting quality of life, and there is no FDA approved specific drug for RiED. We previously showed that prostate RT increased RhoA/ROCK signaling in the cavernous nerve (CN) and penile tissues, which may lead to RiED in rats. In this study, we investigated whether RhoA/ROCK pathway inhibition by a specific inhibitor called Hydroxyfasudil (HF) can improve RiED in our well-established rat model.

MATERIALS/METHODS

Male Sprague-Dawley rats were randomized to the following groups: sham-RT, HF-only, RT-only, and RT + HF. Rats were either exposed to a single dose of 25 Gy prostate-confined RT or a sham procedure. 10 mg/kg HF or normal saline was injected intraperitoneally. Erectile function was evaluated by intracavernosal pressure (ICP) and mean arterial pressure (MAP) measurements at week 14 post-RT. Cavernous nerve (CN) injury was evaluated by transmission electron microscopy (TEM), and penile tissue fibrosis by Masson trichrome staining (MT).

RESULTS

We have found that the HF treatment prior to RT showed significant (p < 0.001) improvement in ICP/MAP ratio, area under the curve, and maximum ICP value, compared to RT-alone rats. Furthermore, RT + HF treated rats exhibited increased CN myelination and decreased axonal atrophy, comparted to RT-only. HF treatment showed significantly decreased penile tissue fibrosis (p < 0.05) compared to RT-alone treated rats.

CONCLUSION

Our results provide the first preclinical evidence that targeting RhoA/ROCK pathway by HF may provide a novel therapeutic option for the treatment of RiED.

Challenges in Reporting the Effect of Radiotherapy on Erectile Function

BACKGROUND

Erectile dysfunction (ED) is the most common side effect of prostate radiotherapy (RT), but reported rates over time and across modalities have varied widely.

AIM

To evaluate the published literature between 2002 and 2018 for high quality data utilizing prospectively gathered patient-reported ED, and to summarize the challenges in reporting of RT-induced ED (RIED).

METHODS

A PubMed search and literature review was performed to identify articles describing rates of ED before and after definitive external beam RT or brachytherapy without androgen deprivation.

OUTCOMES

Patient-reported ED, patient and treatment variables, and study follow-up constituted the main outcomes of this study.

RESULTS

24 articles were identified, reporting RIED rates between 17% and 90%. Variables contributing to this range included patient, treatment, and study characteristics known to impact ED reporting.

CLINICAL IMPLICATIONS

For future studies, we recommend the use of validated patient-reported questionnaires and reporting of baseline function and comorbidities, RT type and dose, and use of androgen deprivation therapy and erectile aids at the time of ED measurement. With sufficient follow-up to understand the late nature of RIED, these recommendations will improve comparison of results between studies and the applicability of results to patients undergoing pretreatment counseling regarding the risks of RIED.

STRENGTHS & LIMITATIONS

The literature search and formulation of results were based on a broad understanding of the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines and the literature, but because of the focus on data reporting, a comprehensive systematic review of all RIED literature was not performed.

CONCLUSION

Reported rates of ED after RT vary widely due to differences in patients' baseline reported erectile function, age, comorbidities, and characteristics of the treatment delivered. The methodology of ED measurement has significant impact on the applicability and comparability of results to other studies and clinical practice. Nukala V, Incrocci L, Hunt AA, et al. Challenges in Reporting the Effect of Radiotherapy on Erectile Function. J Sex Med 2020;17:1053-1059.

The effect of anaemia on normal tissue toxicity and survival outcomes in prostate cancer treated with radical radiotherapy and neo-adjuvant androgen deprivation

OBJECTIVE

It has been established that survival and toxicity outcomes in some cancer types could be influenced by haemoglobin (Hb) levels. This study aims to determine if pre-treatment Hb is associated with late toxicity or survival outcomes in prostate cancer.

METHODS

Data from one Phase III randomised controlled trial and one single arm translational trial were analysed. Patients had localized prostate cancer and received ≥70 Gy radiotherapy and neo-adjuvant androgen deprivation between 1997 and 2013.

RESULTS

302 males were included. Median follow-up was 6.8 years for toxicity and 10.3 years for survival outcomes. Patients with Hb below the reference range were more likely to experience Grade 2-3 late gastrointestinal toxicity than patients with Hb within the range (p = 0.050). Neither late genitourinary toxicity, erectile function toxicity, prostate-specific antigen relapse free survival nor overall survival of patients were statistically significantly different between groups.

CONCLUSION

Anaemia in prostate cancer is found in the minority of patients and is usually mild. Prostate cancer patients undergoing radiotherapy with low Hb were more likely to experience Grade 2-3 late gastrointestinal toxicity.

ADVANCES IN KNOWLEDGE

This study is one of the first in the published literature to investigate the role of Hb in prostate cancer toxicity and survival. We have found an association between Hb below the reference range and late GI toxicity. Consideration should be given to further investigating patients with iron deficiency anaemia to guide management options and outrule underlying GI pathology before proceeding with radiotherapy treatment.

A Systematic Review of Sexual Satisfaction in Prostate Cancer Patients

INTRODUCTION

Prostate cancer (PCa) treatment has a significant negative impact on sexual function. Because research to this date has mostly focused on the impact of PCa on erectile function, very little is known about the impact of PCa on other relevant sexual outcomes, such as sexual satisfaction.

AIM

To conduct a literature review of studies that have examined sexual satisfaction in men diagnosed with and treated for PCa.

METHODS

A systematic review was conducted using Scopus and PubMed databases to identify studies that had assessed sexual satisfaction in men with PCa. The main characteristics of each study and results regarding the impact of PCa on sexual satisfaction were extracted and examined.

MAIN OUTCOME MEASURE

The main outcome measure was studies that assessed general sexual satisfaction in men with PCa.

RESULTS

Thirty-eight articles were found regarding sexual satisfaction in PCa. Most studies did not focus on sexual satisfaction specifically, and methodologic limitations produced very mixed results. Overall, PCa treatments had a low to moderate impact on sexual satisfaction, and psychosocial interventions were more successful at improving sexual satisfaction than medical interventions. Sexual satisfaction was correlated to a large number of sexual, relational, psychological, and medical variables.

CONCLUSION

This literature review shows very mixed results about the sexual satisfaction in men with PCa. Differences in research designs, methodologic limitations, and studies conducted atheoretically limit our understanding of the mechanisms that impact sexual satisfaction in men with PCa. We propose an alternative way of conducting research on sexual satisfaction by using solid theoretical models of sexual satisfaction. Santos-Iglesias P, Rana M, Walker L. A Systematic Review of Sexual Satisfaction in Prostate Cancer Patients. Sex Med Rev 2020;8:450-465.

A systematic review of radiation-induced testicular toxicities following radiotherapy for prostate cancer

BACKGROUND

Prostate cancer is the second most common malignancy in men in the world, and radiotherapy is used as a standard treatment modality for this cancer. Although this treatment modality effectively kills prostate cancerous cells, it unavoidably irradiates the organs/tissues that are away from the treatment site. In this regard, radiation-induced testicular toxicities following prostate radiotherapy can affect sexual function, reproduction, and quality of life in cancer survivors. This review summarizes the available data on testicular exposure to radiation during prostate radiotherapy and the consequences on testicular function.

METHODS

To illuminate the radiation-induced testicular toxicities following prostate radiotherapy, a systematic search was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline in PubMed, Web of Science, Scopus, Embase, and clinical trials electronic databases up to September 2018. According to a set of prespecified inclusion and exclusion criteria, 31 eligible articles providing data on testicular function following radiotherapy in patients with prostate cancer were included in the study.

RESULTS

According to the different radiotherapeutic techniques used for prostate cancer treatment, the total tumor dose and scattered testicular dose values were ranging from 36.25 to 78.00 Gy and 0.06 to 6.48 Gy, respectively. Luteinizing hormone and follicle-stimulating hormone levels after prostate radiotherapy were significantly higher in comparison with the pretreatment levels. Around 60% of the studies showed that testosterone levels after prostate radiotherapy were significantly lower than the pretreatment levels. Furthermore, erectile dysfunction (ED), as an adverse side effect resulting from prostate radiotherapy, was reported and this complication is significantly correlated with lower satisfaction with sexual life. Testicular atrophy following prostate radiotherapy has also been observed and its frequency in patients with prior prostate radiotherapy is 2.5 times more than that in the patients without prior radiotherapy.

CONCLUSION

The data revealed that the scattered dose to testicular tissues during prostate radiotherapy can lead to testicular atrophy, variation of the male sex hormones, and quality of sexual life.

Dose to penile bulb is not associated with erectile dysfunction 18 months post radiotherapy: A secondary analysis of a randomized trial

Background

Erectile dysfunction is a common side effect of prostate cancer (PC) therapy. In this randomized study (The RIC-study) we used patient reported outcomes to evaluate sexual function 18 months after combined endocrine therapy and radical radiotherapy (RT) given with either wide or tight planning target volume (PTV) margins. We also analyzed the impact of radiation dose to penile bulb on sexual function.

Methods

The RIC-study included 257 men with intermediate and high-risk PC. All patients received 6 months of total androgen blockage started 3 months prior to randomization. In high-risk patients, an oral anti-androgen (Bicalutamide) was administered for an additional 2.5 years. Patients were randomized to receive 78 Gy in 39 fractions guided either by weekly offline orthogonal portal imaging or by daily online cone beam computed tomography image-guided RT. Sexual function was evaluated at 18 months after start of RT using the Questionnaire Umeå Fransson Widmark 1994. Ability to have an erection was assessed on an 11-point scale numerical rating scale (0 = no and 10 = very much) as the primary outcome. In addition, the association between penile bulb (PB) radiation dose and erectile function was analyzed.

Findings

Of 250 evaluable patients, 228 (mean age 71.8 years) returned the questionnaires. The patients reported a high degree of sexual related problems with mean scores to the primary outcome question (221 respondents) of 7.44 and 7.39 in the 2D weekly IGRT-arm and 3D daily IGRT-arm (p = 0.93) respectively. For four additional questions (scale 0–10) regarding sexual function resulted in mean scores >6.5 with no difference between study arms. The mean dose to PB was substantially larger in the 2D weekly IGRT-arm vs the 3D daily IGRT-arm (mean 59.8 Gy vs mean 35.1 Gy).

We found no effect of mean PB-dose on the primary outcome adjusted for study-site, risk-group and age. When adjusting for serum-testosterone level at 18 months in addition, the effect of mean PB-dose remained insignificant.

Interpretation

IGRT protocol or PB dose had no effect on ED 18 months after RT in this study population. The low potency rates can partly be explained by the prolonged use of anti-androgen in high risk patients. Longer follow-up is needed to confirm the results from the RIC-study.

Erectile Dysfunction: AUA Guideline

PURPOSE

The purpose of this guideline is to provide a clinical strategy for the diagnosis and treatment of erectile dysfunction.

MATERIALS AND METHODS

A systematic review of the literature using the Pubmed, Embase, and Cochrane databases (search dates 1/1/1965 to 7/29/17) was conducted to identify peer-reviewed publications relevant to the diagnosis and treatment of erectile dysfunction. Evidence-based statements were based on body of evidence strength Grade A, B, or C and were designated as Strong, Moderate, and Conditional Recommendations with additional statements presented in the form of Clinical Principles or Expert Opinions.

RESULTS

The American Urological Association has developed an evidence-based guideline on the management of erectile dysfunction. This document is designed to be used in conjunction with the associated treatment algorithm.

CONCLUSIONS

Using the shared decision-making process as a cornerstone for care, all patients should be informed of all treatment modalities that are not contraindicated, regardless of invasiveness or irreversibility, as potential first-line treatments. For each treatment, the clinician should ensure that the man and his partner have a full understanding of the benefits and risk/burdens associated with that choice.

Reporting Erectile Function Outcomes After Radiation Therapy for Prostate Cancer: Challenges in Data Interpretation

BACKGROUND

Choice of prostate cancer treatment is frequently influenced by the expected chance of treatment-induced side effects such as erectile dysfunction (ED). However, great discrepancy in cited ED rates exists in the contemporary radiation therapy literature.

AIM

To analyze the reported ED rates and cause of discrepancies and explore the strengths and limitations in the literature on radiation-induced ED.

METHODS

We performed a PubMed literature search and reviewed the literature on ED rates associated with external-beam radiotherapy and brachytherapy from the past 10 years. Eighteen studies were eligible for inclusion and subsequently reviewed.

OUTCOMES

Variables required for interpretation of erectile function outcomes, including patient demographics, treatment characteristics, and sexual function outcomes.

RESULTS

A large variety in the reported incidence of ED was found among studies. In part, these differences resulted from large variations in (i) study populations, (ii) patient characteristics, (iii) treatment characteristics, (iv) prescription of androgen deprivation therapy, (v) means of data acquisition, (vi) definitions of ED, (vii) temporal considerations, and (viii) erectile aid use. Relevant data required for adequate appraisal of sexual function outcomes were not always reported.

CLINICAL IMPLICATIONS

Based on the present findings, we present general recommendations for reporting of erectile function outcomes after radiotherapy for prostate cancer. These should improve future reports.

STRENGTHS AND LIMITATIONS

This is the first report that presents general requirements on reporting erectile function outcomes in the setting of radiotherapy for prostate cancer. We did not conduct a formal meta-analysis because we focused on concepts of research design; this might be considered a limitation.

CONCLUSION

In this review, we have highlighted the strengths and deficiencies of the current literature on ED after external-beam radiotherapy and brachytherapy for prostate cancer. We have made general recommendations to achieve some degree of standardization among reports and improve clinical interpretability. Wortel RC, Incrocci L, Muhall JP. Reporting Erectile Function Outcomes After Radiation Therapy for Prostate Cancer: Challenges in Data Interpretation. J Sex Med 2017;14:1260-1269.

Prospective evaluation of a specific technique of sexual function preservation in external beam radiotherapy for prostate cancer

OBJECTIVE

Sexual preservation is an important issue in the treatment of localized prostate cancer. A technique of irradiation was developed to better preserve this function and has been evaluated.

METHODS

Eleven patients, with no erectile dysfunction (ED), were treated with daily IMRT-IGRT (total dose: 76-78 Gy). The pudendal arteries, penile bulb and cavernous body were delineated on the planning CT scan. The doses to these structures (with a 5 mm margin) were optimized to be as low as possible. The erectile function was documented using IIEF-5 scores at baseline, 6 months, 1 and 2 years. No ED was defined by an IIEF5 ≥ 20/25, a mild ED by an IIEF5 score of 17-19 and an important ED by a score <17.

RESULTS

The mean age was 68.4 years. At the median follow-up of 36 months, there was no biochemical relapse. Before RT, the mean IIEF5 score in all 11 patients was 23.4 (range, 20-25). At 6, 12, 18 and 24 months after RT, the mean IIEF scores were 21.2 (14-25), 21.3 (14-25), 21.8 (16-25) and 21.8 (16-25), respectively. At 2 years, 8 patients (72.7%) had no ED and 2 patients (18.2%) experienced a mild ED. The only patient with an important ED had a medical treatment and recovered a satisfactory IIEF score from 16 to 24.

CONCLUSION

The results of this technique of optimisation for sexual preservation are encouraging. Despite a mean age close to 70 years at the time of treatment, 90.9% of the patients had no to mild ED at 2 years. This rate increases at 100% with medical treatment. Advances in knowledge: Dose optimization on sexual organs is possible and could decrease the ED rates.

Pelvic symptoms after radiotherapy in prostate cancer: a cross-sectional study

Abstract Introduction: Despite the technical and scientific progress that improved therapeutic resources available in Oncology, adverse effects of treatment can be prominent, impacting the quality of life (QoL). Objective: This research aims to determine the prevalence of post-radiotherapy pelvic symptoms in prostate cancer (PC) and its impact on QoL. Methods: We assessed three groups of patients at different stages during radiotherapy (RT): Pre-RT, evaluated before of RT; Post-RT#1, evaluated between six months and one year post-RT; Post-RT#2, evaluated between two and a half and four years post-RT. The presence of urinary incontinence (UI), its characteristics and impact on daily living activities (DLA) were evaluated by ICIQ-SF questionnaire. WHOQOL-BREF questionnaire was used to assess QoL. Student t test was used, considering significant p < 0.05. Results: Thirty-three men were assessed (pre-RT, n = 12; Post-RT#1, n = 10; Post-RT#2, n = 11). The prevalence of lower urinary tract symptoms (LUTS) was highest in Post-RT#1 group. Post-RT#2 group had the highest prevalence of post-RT UI. In QoL, Pre-RT and Post-RT#2 groups experiencing the greatest impact on physical, environmental and overall QoL. Conclusion: Acute effect of RT is characterized by a high prevalence of LUTS. Post-RT#2 group experienced the most adverse effects on DLA due to a higher prevalence of post-RT UI.

Radiation-induced erectile dysfunction: Recent advances and future directions

Prostate cancer is one of the most prevalent cancers and the second leading cause of cancer-related deaths in men in the United States. A large number of patients undergo radiation therapy (RT) as a standard care of treatment; however, RT causes erectile dysfunction (radiation-induced erectile dysfunction; RiED) because of late side effects after RT that significantly affects quality of life of prostate cancer patients. Within 5 years of RT, approximately 50% of patients could develop RiED. Based on the past and current research findings and number of publications from our group, the precise mechanism of RiED is under exploration in detail. Recent investigations have shown prostate RT induces significant morphologic arterial damage with aberrant alterations in internal pudendal arterial tone. Prostatic RT also reduces motor function in the cavernous nerve which may attribute to axonal degeneration may contributing to RiED. Furthermore, the advances in radiogenomics such as radiation induced somatic mutation identification, copy number variation and genome-wide association studies has significantly facilitated identification of biomarkers that could be used to monitoring radiation-induced late toxicity and damage to the nerves; thus, genomic- and proteomic-based biomarkers could greatly improve treatment and minimize arterial tissue and nerve damage. Further, advanced technologies such as proton beam therapy that precisely target tumor and significantly reduce off-target damage to vital organs and healthy tissues. In this review, we summarize recent advances in RiED research and novel treatment modalities for RiED. We also discuss the possible molecular mechanism involved in the development of RiED in prostate cancer patients. Further, we discuss various readily available methods as well as novel strategies such as stem cell therapies, shockwave therapy, nerve grafting with tissue engineering, and nutritional supplementations might be used to mitigate or cure sexual dysfunction following radiation treatment.

Sexual Concerns after (Pelvic) Radiotherapy: Is There Any Role for the Radiation Oncologist?

INTRODUCTION

Sexual function is an important aspect of quality of life, and may be impaired after (pelvic) radiation.

AIM

The aim of this study was to identify practice, responsibility attitudes, knowledge, and barriers of Dutch radiation oncologists regarding sexual counseling.

METHODS

A cross-sectional survey was performed using a 28-item questionnaire sent to all members of the Dutch Society for Radiotherapy and Oncology.

MAIN OUTCOME MEASURES

Self-reported practice, knowledge, barriers, need for training and responsibility attitudes in regard to demographic characteristics.

RESULTS

Of the surveyed sample, 54.6% of the radiation oncologists completed the instrument (n = 119). Frequency of discussing sexual function was fluctuating, depending on the type of tumor. The majority of the responding radiation oncologists (75%) agreed that discussing sexual function is their responsibility, about one-third (33.6%) pointed at the involved specialist (surgeon, urologist, gynecologist, or oncologist), a fifth also considered the general practitioner responsible (21%). Additional training about discussing sexuality was required according to 44.4%, the majority agreed that sexual counseling should be a regular component of radiation oncology residency (n = 110, 94%). Barriers most mentioned included patient is too ill (36.2%), no angle or reason for asking (32.4%), advanced age of the patient (27%) and culture/religion (26.1%). For prostate cancer patients, phosphodiesterase 5 inhibitor information was supplied regularly (49.2%) and often (40.7%).

CONCLUSIONS

Radiation oncologists generally perform sexual counseling in case of pelvic radiation therapy, but not consistently in case of gastrointestinal, breast, and other cancers. The majority of radiation oncologists considered counseling on sexual functioning as a part of their job, some also pointed at the referring specialist or general practitioner. The findings suggest that awareness about sexual dysfunction is present among radiation oncologists, but responsibility for active counseling is uncertain. Results emphasize the need for providing educational and practical training, as well as a list for specialized referral.

Sexual function and male cancer

Quality of life in general and sexual functioning in particular have become very important in cancer patients. Biological factors such as anatomic alterations, physiological changes and secondary effect of medical interventions may preclude normal sexual functioning even when sexual desire is intact. In spite of modern surgical techniques, improved chemotherapeutical drugs and sophisticated radiation techniques, still many patients complain of impaired sexual function after cancer treatment. A large number of instruments already exist to assess quality of life in cancer patients. It is important to standardize procedures and to use validated questionnaires. Collecting data on an ongoing basis before and long after treatment is mandatory, and control groups must be used. Patients should be offered sexual counselling and informed about the availability of therapies for sexual dysfunctions. In this paper we review the topic of sexual functioning after treatment (predominantly after radiotherapy) of the most common malignancies in men and give suggestions for treatment.

Pharmacologic and surgical therapies for sexual dysfunction in male cancer survivors

The recent recognition that many men experience sexual dysfunction following their diagnosis and treatment of genitourinary cancers, has led to the development multiple varied strategies that attempt to restore or preserve that function. In this manuscript we review the understanding of why it happens, highlight novel management strategies and discuss the concept of penile rehabilitation (PR) following prostate cancer (PCa) treatment, glans preserving strategies among men diagnosed with penile cancer and address the controversial issue of testosterone therapy in men with PCa.

Radiotherapy for prostate cancer and sexual health

Sexual dysfunction is very common after treatment of prostate cancer. Radiation therapy together with radical prostatectomy is the most effective treatment for localized disease. Percentages of erectile dysfunction (ED) reported in prospective studies after external-beam radiotherapy (RT) vary from 60-70%, and these are similar after brachytherapy. In randomized trials more realistic percentages of 30-40% are reported. Modern techniques do not seem to decrease post-radiation ED. No final conclusions can be drawn whether or not the radiation dose to the penile structures correlates with post-radiation ED in patients treated for prostate cancer. The etiology of ED after RT of prostate cancer is most probably multi-factorial. The phosphodiesterase type 5 inhibitors (PDE5-I) sildenafil and tadalafil have been shown to be effective to treat post-radiation ED in about half of the patients in randomized trials. Patients and their partners need to be adequately counselled on the effects of cancer treatment on their sexual life and relationship, and about the different treatment possibilities. Sexual counselling has not become yet a routine part of oncology care in most hospitals, but this should be provided. Due to the lack of robust data, prevention of post-radiation ED with PDE5-I cannot be recommended so far.

Erectile function following brachytherapy, external beam radiotherapy, or radical prostatectomy in prostate cancer patients

BACKGROUND AND PURPOSE

For localized prostate cancer, treatment options include external beam radiotherapy (EBRT), radical prostatectomy (RP), and brachytherapy (BT). Erectile dysfunction (ED) is a common side-effect. Our aim was to evaluate penile erectile function (EF) before and after BT, EBRT, or RP using a validated self-administered quality-of-life survey from a prospective registry.

MATERIAL AND METHODS

Analysis included 478 patients undergoing RP (n = 252), EBRT (n = 91), and BT (n = 135) with at least 1 year of follow-up and EF documented using IIEF-5 scores at baseline, 6 weeks, 6 months, 1 year, and annually thereafter.

RESULTS

Differences among treatments were most pronounced among patients with no or mild initial ED (IIEF-5 ≥ 17). Overall, corrected for baseline EF and age, BT was associated with higher IIEF-5 scores than RP (+ 7.8 IIEF-5 score) or EBRT (+ 3.1 IIEF-5 score). EBRT was associated with better IIEF-5 scores than RP (+ 4.7 IIEF-5 score). In patients undergoing EBRT or RP with bilateral nerve sparing (NS), recovery of EF was observed and during follow-up, the differences to BT were not statistically significant. Overall age had a negative impact on EF preservation (corrected for baseline IIEF).

CONCLUSION

In our series, EF was adversely affected by each treatment modality. Considered overall, BT provided the best EF preservation in comparison to EBRT or RP.

Pilot Study Evaluating a Rat Model of Radiation-induced Erectile Dysfunction Using an Image-guided Microirradiator

OBJECTIVE

To establish a feasible rat model of radiation-induced erectile dysfunction after targeted prostate irradiation using an image-guided irradiation unit specially designed for small-animal radiation research.

METHODS

The X-RAD 225Cx research platform was used in the present study. We first performed quality assurance testing using a rat cadaver. After confirming dosimetry, 24 age-matched, young, adult, male rats were assigned to sham radiation or radiation to the prostate with doses of 15, 20, or 25 Gy. To confirm appropriate prostate irradiation, physiological erectile function was evaluated using intracavernous pressure (ICP) measurements with cavernous nerve electrical stimulation at 9 weeks after radiotherapy. Each animal was weighed at the time of ICP measurement. In addition, we investigated the cyclic guanosine monophosphate level in the penile cavernosa using a commercial enzyme-linked immunosorbent assay kit.

RESULTS

Quality assurance results confirmed the accuracy of the irradiation technique. Dose-dependent decreases in ICP in irradiated rats were observed without major toxicity. No difference in body weight was noted among the experimental groups. Cyclic guanosine monophosphate levels were significantly decreased in the group that received 25 Gy compared with the age-matched sham-irradiated group.

CONCLUSION

High-precision imaging and targeting capabilities provided by the micro-IGRT platform enable us to develop a reproducible animal model of radiation-induced erectile dysfunction in prostate cancer research.

Potency preservation following stereotactic body radiation therapy for prostate cancer

BACKGROUND

Erectile dysfunction after prostate radiation therapy remains an ongoing challenge and critical quality of life issue. Given the higher dose of radiation per fraction using stereotactic body radiation therapy (SBRT) there is concern that post-SBRT impotency would be higher than conventional radiation therapy approaches. This study sought to evaluate potency preservation and sexual function following SBRT for prostate cancer.

METHODS

Between February 2008 and March 2011, 216 men with clinically localized prostate cancer were treated definitively with SBRT monotherapy at Georgetown University Hospital. Potency was defined as the ability to have an erection firm enough for intercourse with or without sexual aids while sexual activity was defined as the ability to have an erection firm enough for masturbation and foreplay. Patients who received androgen deprivation therapy (ADT) were excluded from this study. Ninety-seven hormone-naïve men were identified as being potent at the initiation of therapy and were included in this review. All patients were treated to 35-36.25 Gy in 5 fractions delivered with the CyberKnife Radiosurgical System (Accuray). Prostate specific antigen (PSA) and total testosterone levels were obtained pre-treatment, every 3 months for the first year and every 6 months for the subsequent year. Sexual function was assessed with the Sexual Health Inventory for Men (SHIM), the Expanded Prostate Index Composite (EPIC)-26 and Utilization of Sexual Medication/Device questionnaires at baseline and all follow-up visits.

RESULTS

Ninety-seven men (43 low-, 50 intermediate- and 4 high-risk) at a median age of 68 years (range, 48-82 years) received SBRT. The median pre-treatment PSA was 5.9 ng/ml and the minimum follow-up was 24 months. The median pre-treatment total serum testosterone level was 11.4 nmol/L (range, 4.4-27.9 nmol/L). The median baseline SHIM was 22 and 36% of patients utilized sexual aids prior to treatment. Although potency rates declined following treatment: 100% (baseline); 68% (6 months); 62% (12 months); 57% (18 months) and 54.4% (24 months), 78% of previously potent patients had erections sufficient for sexual activity at 24 months post-treatment. Overall sexual aid utilization increased from 36% at baseline to 49% at 24 months. Average EPIC sexual scores showed a slow decline over the first two years following treatment: 77.6 (baseline); 68.7 (6 months); 63.2 (12 months); 61.9 (18 months); 59.3 (24 months). All sexual functions including orgasm declined with time. Prior to treatment, 13.4% of men felt their sexual function was a moderate to big problem which increased to 26.7% two years post treatment. Post-treatment testosterone levels gradually decreased with a median value at two year follow-up of 10.7 nmol/L. However, the average EPIC hormonal scores did not illustrate a statistically significant difference two years post-treatment. Review of the radiation doses to the penile bulb in this study, a potential marker of post-treatment sexual function, revealed that the dose was relatively low and at these low doses the percentage of the penile bulb receiving 29.5 Gy did not correlate with the development of ED.

CONCLUSIONS

Men undergoing SBRT monotherapy for prostate cancer report sexual outcomes comparable to those reported for conventional radiation modalities within the first 24 months after treatment. Longer follow-up is required to confirm the durability of these findings.

Erectile function after permanent 125I prostate brachytherapy for localized prostate cancer

BACKGROUND AND PURPOSE

To analyze erectile function in men treated by prostate brachytherapy (PB) for localized prostate cancer.

MATERIAL AND METHODS

Of a series of 270 sexually active men treated by PB, 241 (89%), mean age 65 yr (range, 43-80 yr), participated in a study on erectile function that was evaluated using the International Index of Erectile Function 5-item (IIEF-5) questionnaire before implantation and by postal survey after a mean follow-up of 36 months (range, 6-70 months).

RESULTS

After PB, 27 patients (11%) had no erectile dysfunction (ED), 36 (15%) had mild ED, 58 (24%) had mild to moderate ED, 24 (10%) had moderate ED, 53 (22%) had severe ED and 43 (18%) were not sexually active. In patients with a preimplant IIEF score >12 (cut-off for intercourse with penetration), 73% had a deterioration of erectile function by at least one class after PB. Risk factors for ED after PB were age, preimplant IIEF score and prostate volume. Median time to ED onset was 16 months and was shorter with androgen deprivation (p = 0.007), diabetes (p = 0.03) and age over 55 (p = 0.01).

CONCLUSIONS

Following PB, the majority of patients progressively develop or major ED after a free interval that may last several months.

SUPPORT

Ligue Nationale contre le Cancer, France.

Impact of sildenafil on marital and sexual adjustment in patients and their wives after radiotherapy and short-term androgen suppression for prostate cancer: analysis of RTOG 0215

PURPOSE

The Radiation Therapy Oncology Group (RTOG) 0215 investigated the efficacy of sildenafil in improving erectile dysfunction following radiotherapy and neoadjuvant/concurrent androgen deprivation therapy among prostate cancer patients and found a significant improvement on drug but only in 21% of study participants. This paper reports on a secondary aim to investigate the effect of sildenafil on overall sexual and marital adjustment among both patients and their wives.

METHODS

RTOG 0215 was a placebo-controlled, double-blind, crossover trial of sildenafil. Participation of wives was optional. Twenty-four married heterosexual couples (33% of heterosexual couples in study) completed the Sexual Adjustment Questionnaire and Locke's Marital Adjustment Test. Treatment differences in mean change scores were evaluated by paired t-tests, and the proportion of patients achieving a clinically meaningful change was evaluated using chi-square tests. Spearman's correlation coefficients were used to determine the association of adjustment between patients and wives.

RESULTS

There was no significant change in either sexual or marital adjustment for patients. For wives, there was a trend for improvement in sexual adjustment but no significant change in marital adjustment. Change in marital adjustment between patients and wives was weakly related (r(s) = 0.15, p = 0.48), and for sexual adjustment, there was a moderate, but nonsignificant relationship (r(s) = 0.40, p = 0.09).

CONCLUSIONS

Larger studies are warranted to further examine possible differences in sexual experiences and treatment needs between prostate cancer patients and their wives, as well as to assess predictors of sildenafil response.

Erectile dysfunction after prostate three-dimensional conformal radiation therapy. Correlation with the dose to the penile bulb

PURPOSE

Erectile dysfunction is associated with all the common treatment options for prostate cancer. The aim of this research was to evaluate the relationship between erectile function and radiation dose to the penile bulb (PB) and other proximal penile structures in men receiving conformal radiotherapy (CRT) without hormonal therapy (HT) for prostate cancer, whose sexual function was known before treatment.

PATIENTS AND METHODS

The study included 19 patients treated with 3D-CRT for localized prostate cancer at our department, who were self-reported to be potent before treatment, had not received HT, and had complete follow-up data available. Our evaluation was based on the International Index of Erectile Function (IIEF-5). Dose-volume histograms (DVHs) were used to evaluate the dose to the PB. Statistical analysis was performed with an unconditional logistic regression model.

RESULTS

All patients reported change in potency after radiation. Eight patients (42%) remained potent but showed a decrease of 1 or 2 levels of potency, as defined by the IIEF-5 questionnaire (reduced potency group), while 11 patients (58%) reported a change of higher levels and revealed a severe erectile dysfunction after 2 years (impotence group). Multivariate analysis of morphological and dosimetric variables yielded significance for the mean dose (p = 0.05 with an odds ratio of 1.14 and 95% CI 1-1.30). Patients receiving a mean dose of less than 50 Gy to the PB appear to have a much greater likelihood of maintaining potency.

CONCLUSION

Our data suggest a possible existence of a dose-volume correlation between the dose applied to the PB and radiation-induced impotence.

Sexuality in adult cancer survivors: challenges and intervention

Sexual dysfunction is one of the most common and distressing consequences of cancer treatment. Although some treatment-related sexual adverse effects are short-term, many survivors face long-term effects such as treatment-induced menopause, altered gonadal function, and significant surgical disfigurement. Profound sexual dysfunction has been shown to have a significant negative effect on quality of life. Although these problems have been well documented and there are a range of intervention strategies that can help patients cope with treatment-related sexual problems, many survivors do not feel prepared for potential sexual changes and often do not receive adequate support to manage sexual dysfunction. Numerous barriers contribute to this underprovided aspect of survivorship care, including lack of provider training and access to readily available resources. In addition, psychological, relational, and cultural factors significantly influence sexuality but are often not taken into consideration in research and clinical practice. By taking an integrative approach and providing survivors with appropriate screening, information, and support, sexual dysfunction and accompanying distress can be significantly alleviated. In this article, we aim to provide a concise review of the most common sexual problems experienced by survivors and highlight some of the most promising evidence-based practices for assessment and intervention. We also address limitations encountered in research and practice and explore future directions, including suggestions for adopting an integrative treatment model to address sexual dysfunction in a cancer survivorship treatment setting.

Quality-of-life outcomes in high-risk prostate cancer patients treated with helical tomotherapy in a hypofractionated radiation schedule with long-term androgen suppression

PURPOSE

We examined the impact of hypofractionated radiation therapy and androgen suppression therapy (AST) on quality of life (QOL) in high-risk prostate cancer patients.

METHODS

Between March 2005 and March 2007, 60 patients with high-risk prostate cancer were enrolled in a prospective phase ii study. All patients received 68 Gy (2.72 Gy per fraction) to the prostate gland and 45 Gy (1.8 Gy per fraction) to the pelvic lymph nodes in 25 fractions over 5 weeks. Of the 60 patients, 58 received ast. The University of California-Los Angeles Prostate Cancer Index questionnaire was used to prospectively measure QOL at baseline (month 0) and at 1, 6, 12, 18, 24, 30, and 36 months after radiation treatment. The generalized estimating equation approach was used to compare the QOL scores at 1, 6, 12, 18, 24, 30, and 36 months with those at baseline.

RESULTS

We observed a significant decrease in QOL items related to bowel and sexual function. Several QOL items related to bowel function were significantly adversely affected at both 1 and 6 months, with improvement toward 6 months. Although decreased QOL scores persisted beyond the 6-month mark, they began to re-approach baseline at the 18- to 24-month mark. Most sexual function items were significantly adversely affected at both 1 and 6 months, but the effects were not considered to be a problem by most patients. A complete return to baseline was not observed for either bowel or sexual function. Urinary function items remained largely unaffected, with overall urinary function being the only item adversely affected at 6 months, but not at 1 month. Urinary function returned to baseline and remained unimpaired from 18 months onwards.

CONCLUSIONS

In our study population, who received hypofractionated radiation delivered using dynamic intensity-modulated radiotherapy with inclusion of the pelvic lymph nodes, and 2-3 years of ast prescription, QOL with respect to bowel and sexual function was significantly affected; QOL with respect to urinary function was largely unaffected. Our results are comparable to those in other published studies.

[The impact of radiation therapy on sexual function]

The aim of this study was to evaluate the impact of radiation therapy on sexual life. The analysis was based on a Pubmed literature review. The keywords used for this research were "sexual, radiation, oncology, and cancer". After a brief reminder on the anatomy and physiology, we explained the main complications of radiation oncology and their impact on sexual life. Preventive measures and therapeutic possibilities were discussed. Radiation therapy entails local, systematic and psychological after-effects. For women, vaginal stenosis and dyspareunia represent the most frequent side effects. For men, radiation therapy leads to erectile disorders for 25 to 75% of the patients. These complications have an echo often mattering on the patient quality of life of and on their sexual life post-treatment reconstruction. The knowledge of the indications and the various techniques of irradiation allow reducing its potential sexual morbidity. The information and the education of patients are essential, although often neglected. In conclusion, radiation therapy impacts in variable degrees on the sexual life of the patients. Currently, there are not enough preventive and therapeutic means. Patient information and the early screening of the sexual complications are at stake in the support of patients in the reconstruction of their sexual life.

Treatment outcome of high-dose image-guided intensity-modulated radiotherapy using intra-prostate fiducial markers for localized prostate cancer at a single institute in Japan

Background

Several studies have confirmed the advantages of delivering high doses of external beam radiotherapy to achieve optimal tumor-control outcomes in patients with localized prostate cancer. We evaluated the medium-term treatment outcome after high-dose, image-guided intensity-modulated radiotherapy (IMRT) using intra-prostate fiducial markers for clinically localized prostate cancer.

Methods

In total, 141 patients with localized prostate cancer treated with image-guided IMRT (76 Gy in 13 patients and 80 Gy in 128 patients) between 2003 and 2008 were enrolled in this study. The patients were classified according to the National Comprehensive Cancer Network-defined risk groups. Thirty-six intermediate-risk patients and 105 high-risk patients were included. Androgen-deprivation therapy was performed in 124 patients (88%) for a median of 11 months (range: 2–88 months). Prostate-specific antigen (PSA) relapse was defined according to the Phoenix-definition (i.e., an absolute nadir plus 2 ng/ml dated at the call). The 5-year actuarial PSA relapse-free survival, the 5-year distant metastasis-free survival, the 5-year cause-specific survival (CSS), the 5-year overall survival (OS) outcomes and the acute and late toxicities were analyzed. The toxicity data were scored according to the Common Terminology Criteria for Adverse Events, version 4.0. The median follow-up was 60 months.

Results

The 5-year PSA relapse-free survival rates were 100% for the intermediate-risk patients and 82.2% for the high-risk patients; the 5-year actuarial distant metastasis-free survival rates were 100% and 95% for the intermediate- and high-risk patients, respectively; the 5-year CSS rates were 100% for both patient subsets; and the 5-year OS rates were 100% and 91.7% for the intermediate- and high-risk patients, respectively. The Gleason score (<8 vs. ≥8) was significant for the 5-year PSA relapse-free survival on multivariate analysis (p = 0.044). There was no grade 3 or 4 acute toxicity. The incidence of grade 2 acute gastrointestinal (GI) and genitourinary (GU) toxicities were 1.4% and 8.5%, respectively. The 5-year actuarial likelihood of late grade 2–3 GI and GU toxicities were 6% and 6.3%, respectively. No grade 4 GI or GU late toxicity was observed.

Conclusions

These medium-term results demonstrate a good tolerance of high-dose image-guided IMRT. However, further follow-up is needed to confirm the long-term treatment outcomes.

Chronic low dosing of phosphodiesterase type 5 inhibitor for erectile dysfunction

Oral phosphodiesterase type 5 (PDE5) inhibitors have provided non-invasive, effective, and well-tolerated treatments for patients with erectile dysfunction (ED). However, many patients with ED are unresponsive to 'on-demand' PDE5 inhibitors. In addition, the lack of spontaneity and naturalness of the on-demand regimen could be a reason for decreased compliance with PDE5 inhibitors. Recently, tadalafil and udenafil were approved for low-dose daily administration for the treatment of ED. Since the introduction of the concept of daily administration of PDE5 inhibitors, several reports have supported the potential benefits of this therapy for disease modification, improvement of the treatment response in difficult-to-treat populations, spontaneity, and safety, although further research is needed to better address these hypotheses. In this article, we reviewed the daily administration of PDE5 inhibitors in terms of pharmacokinetics, safety, efficacy, and distinct features.

The effect of short term neo-adjuvant androgen deprivation on erectile function in patients treated with external beam radiotherapy for localised prostate cancer: an analysis of the 4- versus 8-month randomised trial (Irish Clinical Oncology Research Group 97-01)

BACKGROUND AND PURPOSE

Erectile dysfunction is a common consequence of external beam radiotherapy (EBRT) for prostate cancer. The addition of neo-adjuvant androgen deprivation (NAD) has an indeterminate additive effect. We examined the long-term effect on erectile function (EF) of two durations (4 months: arm 1 and 8 months: arm 2) of NAD prior to radiation (RT) for patients with localised prostate cancer from the Irish Clinical Oncology Research Group (ICORG 97-01) 4- versus 8-month trial. In this study we aimed to (1) analyse the overall effect on EF of NAD in an EBRT population, (2) compare the probability of retained EF over time in an EBRT population treated with either 4 or 8 months of NAD and (3) identify any variables such as risk group and age which may have an additive detrimental effect. This analysis provides unique long term follow up data.

MATERIALS AND METHODS

From 1997 to 2001, 276 patients with adenocarcinoma of the prostate were randomised to 4 or 8 months of NAD before RT. EF data were recorded at baseline and at each follow-up visit by physician directed questions, using a 4-point grading system.

RESULTS

Two hundred and thirty patients were included in the analysis of EF and were followed for a median of 80 months. One hundred and forty-one patients had EF at baseline. Neo-adjuvant androgen deprivation in addition to radiation therapy caused a significant reduction in EF. The most significant reduction in EF happens within the first year. The median time to grade 3-4 EF toxicity was 14.6 months, 17.6 months in arm 1 and 13.7 in arm 2. Freedom from late EF toxicity did not differ significantly between arms, overall or at 5 years (n=141). The cumulative probability of EF preservation at 5 years was 28% (22-34) in arm 1 and 24% (19-30) in arm 2. Age was a significant predictor of post-treatment EF.

CONCLUSIONS

The first year post ADT and EBRT poses the greatest risk to sexual function and a continued decline may be expected. However, 26% of men can expect to retain sexual function at 5 years.

Role of oxidative stress in a rat model of radiation-induced erectile dysfunction

INTRODUCTION

Chronic oxidative stress is one of the major factors playing an important role in radiation-induced normal tissue injury. However, the role of oxidative stress in radiation-induced erectile dysfunction (ED) has not been fully investigated. Aims.  To investigate role of oxidative stress after prostate-confined irradiation in a rat model of radiation-induced ED.

METHODS

Fifty-four young adult male rats (10-12 weeks of age) were divided into age-matched sham radiotherapy (RT) and RT groups. Irradiated animals received prostate-confined radiation in a single 20 Gy fraction.

MAIN OUTCOME MEASURES

Intracavernous pressure (ICP) measurements with cavernous nerve electrical stimulation were conducted at 2, 4, and 9 weeks following RT. The protein expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits (Nox4 and gp91(phox)), markers of oxidative DNA damage (8-hydroxy-2'-deoxyguanosine [8-OHdG]), lipid peroxidation (4-hydroxynonenal [4HNE]), and inflammatory response including inducible nitric oxide synthase, macrophage activation (ED-1), and nitrotyrosine, and endogenous antioxidant defense by nuclear factor erythroid 2-related factor (Nrf2) were evaluated in irradiated prostate tissue and corpora cavernosa (CC). In addition, we investigated the relationships between results of ICP/mean arterial pressure (MAP) ratios and expression level of oxidative stress markers.

RESULTS

In the RT group, hemodynamic functional studies demonstrated a significant time-dependent decrease in ICP. Increased expression of Nox4, gp91(phox), 8-OHdG, and 4HNE were observed in the prostate and CC after RT. Similarly, expressions of inflammatory markers were significantly increased. There was a trend for increased Nrf2 after 4 weeks. ICP/MAP ratio negatively correlated with higher expression level of oxidative markers.

CONCLUSION

NADPH oxidase activation and chronic oxidative stress were observed in irradiated prostate tissue and CC, which correlated with lower ICP/MAP ratio. Persistent inflammatory responses were also found in both tissues after RT. These findings suggest that oxidative stress plays a crucial role in the development of radiation-induced ED.