Tadalafil for prevention of erectile dysfunction after radiotherapy for prostate cancer: the Radiation Therapy Oncology Group [0831] randomized clinical trial

Deep learning based automatic segmentation of the Internal Pudendal Artery in definitive radiotherapy treatment planning of localized prostate cancer

Background and purpose

Radiation-induced erectile dysfunction (RiED) commonly affects prostate cancer patients, prompting clinical trials across institutions to explore dose-sparing to internal-pudendal-arteries (IPA) for preserving sexual potency. IPA, challenging to segment, isn't conventionally considered an organ-at-risk (OAR). This study proposes a deep learning (DL) auto-segmentation model for IPA, using Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) or CT alone to accommodate varied clinical practices.

Materials and methods

A total of 86 patients with CT and MRI images and noisy IPA labels were recruited in this study. We split the data into 42/14/30 for model training, testing, and a clinical observer study, respectively. There were three major innovations in this model: 1) we designed an architecture with squeeze-and-excite blocks and modality attention for effective feature extraction and production of accurate segmentation, 2) a novel loss function was used for training the model effectively with noisy labels, and 3) modality dropout strategy was used for making the model capable of segmentation in the absence of MRI.

Results

Test dataset metrics were DSC 61.71 ± 7.7 %, ASD 2.5 ± .87 mm, and HD95 7.0 ± 2.3 mm. AI segmented contours showed dosimetric similarity to expert physician's contours. Observer study indicated higher scores for AI contours (mean = 3.7) compared to inexperienced physicians' contours (mean = 3.1). Inexperienced physicians improved scores to 3.7 when starting with AI contours.

Conclusion

The proposed model achieved good quality IPA contours to improve uniformity of segmentation and to facilitate introduction of standardized IPA segmentation into clinical trials and practice.

The Current Trend of Radiation Therapy for Patients with Localized Prostate Cancer

A recent approach to radiotherapy for prostate cancer is the administration of high doses of radiation to the prostate while minimizing the risk of side effects. Thus, image-guided radiotherapy utilizes advanced imaging techniques and is a feasible strategy for increasing the radiation dose. New radioactive particles are another approach to achieving high doses and safe procedures. Prostate brachytherapy is currently considered as a combination therapy. Spacers are useful to protect adjacent organs, specifically the rectum, from excessive radiation exposure.

Effects of tadalafil on sexual behavior of male rats induced by chronic unpredictable mild stress

Background

Few studies have investigated psychogenic sexual dysfunction including psychogenic erectile dysfunction (pED); the effect of tadalafil on sexual behavior of male rats induced by chronic unpredictable mild stress (CUMS) remains unclear.

Aim

The aim was to explore the influence of CUMS on sexual behavior of male rats and the effects of tadalafil on that.

Methods

Adult male rats were divided into 3 groups, including the normal group without CUMS, the model group with 6 weeks' CUMS, and the tadalafil group with treatment of tadalafil during CUMS. CUMS consists of water deprivation, food deprivation, stroboscopic lightning, white noise, cage tilting, weeding packing, and housing 2 unfamiliar rats. The apomorphine test and vaginal smear test were conducted with the aim to screen out male rats with good erectile function and make preparation for the sexual behavior test, respectively.

Outcomes

At the end of the study period, the level of anhedonia and sexual function were evaluated by the sucrose preference test, sexual behavior test, and measurement of serum testosterone, dopamine, and 5-HT.

Results

Sucrose preference showed significant decrease in rats after CUMS. The intromission ratio and total intromission frequency decreased significantly, while the mount latency and ejaculation latency prolonged significantly in CUMS-induced rats when compared with normal rats. Meanwhile, the treatment of tadalafil reversed the level of anhedonia and sexual function in CUMS-induced rats. However, there were no statistical differences in the levels of serum testosterone, dopamine, and 5-HT among groups.

Clinical Implications

The study constructed an animal model that can provide clinical insights into the mechanism of psychogenic sexual dysfunction and supports the application of tadalafil in pED therapy.

Strengths and Limitations

We found that CUMS-induced rats exhibited anhedonia and poor sexual function that could be prevented by tadalafil administration. Future research needs to construct the standard of pED model and explore the mechanism of tadalafil on central nervous system.

Conclusion

Tadalafil could prevent the changes of depression and poor sexual function in rats induced by CUMS, and the method of CUMS and the sexual behavior test should be used in the future for pED modeling.

Long-Term Results of a Phase 3 Randomized Prospective Trial of Erectile Tissue-Sparing Intensity-Modulated Radiation Therapy for Men With Clinically Localized Prostate Cancer

PURPOSE

The objective of this study was to determine whether limiting the doses delivered to the penile bulb (PB) and corporal bodies with intensity modulated radiation therapy (IMRT) preserves erectile function compared with standard IMRT in men with prostate cancer.

METHODS AND MATERIALS

A total of 117 patients with low- to intermediate-risk, clinical T1a-T2c prostate adenocarcinoma were enrolled in a single-institution, prospective, single-blind, phase 3 randomized trial. All received definitive IMRT to 74 to 80 Gy in 37 to 40 fractions and standard IMRT (s-IMRT) or erectile tissue-sparing IMRT (ETS-IMRT), which placed additional planning constraints that limited the D90 to the penile bulb and corporal bodies to ≤15 Gy and ≤7 Gy, respectively. Erectile potency was assessed with components of the International Index of Erectile Function and phosphodiesterase type 5 inhibitor (PDE5) medication records.

RESULTS

Sixty-two patients received ETS-IMRT, and 54 received s-IMRT; 1 patient did not receive radiation therapy. Before treatment, all patients reported erectile potency. No patients received androgen deprivation therapy. In the intention-to-treat analysis, treatment arms did not differ in potency preservation at 24 months (37.1% ETS-IMRT vs 31.5% s-IMRT, P = .53). Of 85 evaluable patients with International Index of Erectile Function and PDE5 medication follow-up, erectile potency was seen in 47.9% of patients in the ETS-IMRT arm and 46.0% of patients in the s-IMRT arm (P = .86). PDE5 inhibitors were initiated in 41.7% of ETS-IMRT patients and 35.1% of s-IMRT patients (P = .54). Among all patients enrolled, there was no difference in freedom from biochemical failure between those treated with ETS-IMRT and s-IMRT (5-year 91.8% vs 90.7%, respectively, P = .77), with a median follow-up of 7.4 years. There were no differences in acute or late gastrointestinal or genitourinary toxicity. An unplanned per-protocol analysis demonstrated no differences in potency preservation or secondary endpoints between patients who exceeded erectile tissue-sparing constraints and those who met constraints, although power was limited by attrition and unplanned dosimetric crossover.

CONCLUSIONS

ETS-IMRT that strictly limits dose to the penile bulb and corporal bodies is safe and feasible. Use of this planning technique did not show an effect on potency preservation outcomes at 2 years, though power to detect a difference was limited.

Current Knowledge on Radiation-Therapy-Induced Erectile Dysfunction in Prostate-Cancer Patients: A Narrative Review

Prostate cancer is the most frequently diagnosed cancer in men in the United States. Among the different available treatment options, radiation therapy is recommended for localized or even advanced disease. Erectile dysfunction (ED) often occurs after radiation therapy due to neurological, vascular, and endocrine mechanisms resulting in arterial tone alteration, pudendal-nerve neuropraxia, and lastly fibrosis. Considering the influence of quality of life on patients’ treatment choice, radiation-therapy-induced ED prevention and treatment are major issues. In this narrative review, we briefly summarize and discuss the current state of the art on radiation-therapy-induced ED in PCa patients in terms of pathophysiology and available treatment options.

Penile Rehabilitation after Prostate Cancer Treatment: Which Is the Right Program?

The management of sexual complications after treatment of localized prostate cancer, such as erectile dysfunction, changes in the length of the penis, pain during sexual intercourse, and lack of orgasm, is still an unsolved problem with an important impact on patients’ quality of life. In this review, we summarize the current scientific literature about the rehabilitation of erectile dysfunction after prostate cancer treatment. The therapy for penile rehabilitation includes different types of treatments: the combination of phosphodiesterase type 5 inhibitors (PDE5-I) and the vacuum erectile device (VED) are considered first-line treatment options. When therapy begins, the duration of treatment, the dosage and the drug used all play very important roles in the treatment outcome. Intracavernous injection (ICI) therapy represents the second-line option for patients ineligible for PDE5-I therapy. Technological development has led to the emergence of devices for the stimulation of the penis without the use of drugs, such as penile vibratory stimulation (PVS) for stimulation of ejaculation in spinal cord injury and low-intensity extracorporeal shockwave therapy (LIESWT). The rapid diffusion of the latter, thanks to its easy use, attains good results without side effects. The panorama of penile rehabilitation after PC treatments is vast and many studies are needed, especially on new technologies, to find the best therapeutic regimen possible, personalized to the patient’s characteristics and the type of treatment for PC.

Radiation-induced circulating myeloid-derived suppressor cells induce systemic lymphopenia after chemoradiotherapy in patients with glioblastoma

Severe and prolonged lymphopenia frequently occurs in patients with glioblastoma after standard chemoradiotherapy and has been associated with worse survival, but its underlying biological mechanism is not well understood. To address this, we performed a correlative study in which we collected and analyzed peripheral blood of patients with glioblastoma (n = 20) receiving chemoradiotherapy using genomic and immune monitoring technologies. RNA sequencing analysis of the peripheral blood mononuclear cells (PBMC) showed an elevated concentration of myeloid-derived suppressor cell (MDSC) regulatory genes in patients with lymphopenia when compared with patients without lymphopenia after chemoradiotherapy. Additional analysis including flow cytometry and single-cell RNA sequencing further confirmed increased numbers of circulating MDSC in patients with lymphopenia when compared with patients without lymphopenia after chemoradiotherapy. Preclinical murine models were also established and demonstrated a causal relationship between radiation-induced MDSC and systemic lymphopenia using transfusion and depletion experiments. Pharmacological inhibition of MDSC using an arginase-1 inhibitor (CB1158) or phosphodiesterase-5 inhibitor (tadalafil) during radiation therapy (RT) successfully abrogated radiation-induced lymphopenia and improved survival in the preclinical models. CB1158 and tadalafil are promising drugs in reducing radiation-induced lymphopenia in patients with glioblastoma. These results demonstrate the promise of using these classes of drugs to reduce treatment-related lymphopenia and immunosuppression.

Management of male sexual dysfunction after cancer treatment

BACKGROUND

With an increase in the number of cancer survivors each year, male sexual dysfunction becomes an important topic for discussion between patients and providers who treat cancer. The aim of this article is to review types and mechanisms of sexual dysfunction after cancer therapy and discuss treatment options.

METHODS

Contemporary concepts regarding male sexual dysfunction after cancer treatment are reviewed and translated for clinical utility.

FINDINGS

To optimize recovery of erectile capacity after erectile dysfunction causing cancer treatments, a penile rehabilitation protocol involving phosphodiesterase inhibitors, vacuum erection device, intra corporal injections, or a combination is likely to provide some degree of clinically significant benefit. Treating hypogonadism post cancer treatment depends on the type of cancer that has been treated and patient comorbidities. Anejaculation after cancer treatments is typically not successfully or reliably treated due to the mechanism and severity of sympathetic nerve injury. Semen cryopreservation prior to cancer treatments that may injure nerve fibers essential for the ejaculatory response is highly recommended.

CONCLUSION

Management of post cancer treatment sexual dysfunction requires identification of this problem and referral to a specialist if necessary. There are several management options available that can greatly enhance quality of life in this often overlooked aspect of post cancer treatment care.

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.

Low dose rate brachytherapy for primary treatment of localized prostate cancer: A systemic review and executive summary of an evidence-based consensus statement

PURPOSE

The purpose of this guideline is to present evidence-based consensus recommendations for low dose rate (LDR) permanent seed brachytherapy for the primary treatment of prostate cancer.

METHODS AND MATERIALS

The American Brachytherapy Society convened a task force for addressing key questions concerning ultrasound-based LDR prostate brachytherapy for the primary treatment of prostate cancer. A comprehensive literature search was conducted to identify prospective and multi-institutional retrospective studies involving LDR brachytherapy as monotherapy or boost in combination with external beam radiation therapy with or without adjuvant androgen deprivation therapy. Outcomes included disease control, toxicity, and quality of life.

RESULTS

LDR prostate brachytherapy monotherapy is an appropriate treatment option for low risk and favorable intermediate risk disease. LDR brachytherapy boost in combination with external beam radiation therapy is appropriate for unfavorable intermediate risk and high-risk disease. Androgen deprivation therapy is recommended in unfavorable intermediate risk and high-risk disease. Acceptable radionuclides for LDR brachytherapy include iodine-125, palladium-103, and cesium-131. Although brachytherapy monotherapy is associated with increased urinary obstructive and irritative symptoms that peak within the first 3 months after treatment, the median time toward symptom resolution is approximately 1 year for iodine-125 and 6 months for palladium-103. Such symptoms can be mitigated with short-term use of alpha blockers. Combination therapy is associated with worse urinary, bowel, and sexual symptoms than monotherapy. A prostate specific antigen <= 0.2 ng/mL at 4 years after LDR brachytherapy may be considered a biochemical definition of cure.

CONCLUSIONS

LDR brachytherapy is a convenient, effective, and well-tolerated treatment for prostate cancer.

Sildenafil Citrate and Risk of Biochemical Recurrence in Prostate Cancer Patients Treated with Radiation Therapy: Post-Hoc Analysis of a Randomized Controlled Trial

BACKGROUND

Sildenafil citrate has been shown to be protective of sexual function when given concurrently and following prostate radiation therapy (RT), but some evidence suggests an increased biochemical recurrence (BCR) risk in patients taking sildenafil after radical prostatectomy.

AIM

To evaluate whether sildenafil use is associated with increased risk of BCR in patients receiving prostate RT, we performed a secondary analysis of a randomized placebo-controlled trial (RPCT) that compared sildenafil citrate to placebo during and after prostate RT.

METHODS

The study population consisted of prostate cancer patients who initiated radiation treatment at our institution and participated in our multi-institutional RPCT that compared 6 months of sildenafil 50 mg once a day to placebo with a 24-month follow-up. Androgen deprivation therapy (ADT) was allowed. Prostate cancer prognostic risk grouping was not an exclusion criterion, but most study participants had low- or intermediate-risk prostate cancer. Statistical analysis was performed using Kaplan-Meier plots and log-rank testing.

OUTCOMES

The primary outcomes of this report were biochemical recurrence and overall survival rates, where BCR was defined according to the Phoenix definition.

RESULTS

Data of 162 men were analyzed. Nine men had inadequate PSA follow-up and the remaining 153 men were included in the final report. Median age was 61 years. At a median follow-up of 8.3 years (range: 3.0-12.2), 5/94 (5.3%) and 2/59 (3.4%) patients developed BCR in the sildenafil and placebo groups, respectively. The 6-year BCR-free survival was 98.8% for all patients, 98.1% for the sildenafil cohort, and 100% for the placebo cohort. The 10-year BCR-free survival was 94.4% for all patients, 95.6% for the sildenafil cohort, and 92.9% for the placebo cohort. There was no difference in BCR-free survival between the sildenafil and placebo groups by log-rank comparison (p = 0.36).

CLINICAL IMPLICATIONS

This analysis informs clinical decision making about the safety of using sildenafil during and after prostate RT.

STRENGTHS AND LIMITATIONS

This study included patients who were treated in the setting of a prospective, randomized placebo-controlled trial, and who attained high medication compliance. However, the study was limited by the post-hoc nature of the analysis, use of ADT in some patients, inadequate study power to detect a difference in BCR between sildenafil and placebo groups.

CONCLUSION

Prophylactic sildenafil citrate was not associated with biochemical recurrence risk in prostate cancer patients treated with radiation. However, the study was inadequately powered to definitively conclude a negative finding.

Analysis of Patient-Reported Outcome Utilization Within National Clinical Trials Network Cooperative Group Radiation Oncology Trials Over the Past 2 Decades

PURPOSE

When treating cancer, both quantity and quality of life are valuable, though oncology trials have long placed greater emphasis on the former. The goal of this work was to evaluate how patient-reported outcomes (PROs) have been incorporated into radiation therapy trials within the National Clinical Trials Network over the last 2 decades to measure quality of life and to assess how PRO data have been disseminated in publications upon trial conclusion.

METHODS AND MATERIALS

This cross-sectional study analyzed the frequency of use of PROs in National Clinical Trials Network cooperative group radiation therapy phase 2 and 3 clinical trials over the past 2 decades. A literature review was performed to determine the publication outcomes of PRO data, including only trials that used PROs in their design and were mature enough to have published results.

RESULTS

Fifty-seven (56.4%) of the 101 trials included in this study included PROs in their design. Brain and head and neck trials demonstrated the largest proportional incorporation of PROs (81.8% and 76.9%, respectively), and thoracic and breast trials used the fewest (18.8% and 37.5%, respectively). The EQ-5D family of questionnaires was the most commonly used PROs, used in 22.8% of trials included. The literature review demonstrated a pattern of increased publication of PRO data alongside survival endpoints in manuscripts derived from these trials over time.

CONCLUSIONS

Though there is room for improvement, the field of radiation oncology has embraced the incorporation of PROs into multicenter, high-impact clinical trials over the past 2 decades and has increased its publication of this data alongside survival data from these trials.

Penile Rehabilitation and Treatment Options for Erectile Dysfunction Following Radical Prostatectomy and Radiotherapy: A Systematic Review

After radical prostatectomy (RP) or radiotherapy (RT) for prostate cancer, erectile dysfunction (ED) is the main complication next to urinary incontinence, affecting quality of life. The pathophysiology of ED after these treatments is believed to include neuropraxia causing reduced oxygenation and structural changes of the tissue in the corpora cavernosa. Next to the option of sparing the nerves during RP, research has been focusing on methods for penile rehabilitation after RP and RT, since it occurs often, even after nerve-sparing techniques were used. In animal studies, the use of phosphodiesterase type 5 inhibitors (PDE5i) after cavernous nerve damage is supported, but results in human studies are contradictory. Non-medical treatment options such as vacuum device therapy, hyperbaric oxygen therapy, yoga, aerobic, or pelvic floor training may be helpful, but evidence is scarce. Clear guidelines for penile rehabilitation are not yet available. However, care and support for ED after RP and RT is highly demanded by a large group of patients, so measures have to be taken even though the evidence is not strong yet. In this systematic review, an overview of the literature for penile rehabilitation and treatment options for ED after RP and RT is provided, using only randomized controlled trials (RCT).

Strategies to Minimize Late Effects From Pelvic Radiotherapy

During the past 30 years, radiation treatment techniques have significantly improved, from conventional external-beam radiation therapy, to three-dimensional conformal radiation therapy, to current intensity-modulated radiation therapy, benefiting patients who undergo treatment of pelvic malignancies. Modern treatment options also include proton beam irradiation as well as low and high dose rate brachytherapy. Although the acute adverse effects of these modalities are well documented in clinical trials, less well known are the true incidence and optimal management of those late adverse effects that can occur months to years later. In a population of survivors of cancer that is steadily increasing, with many such patients receiving radiotherapy at some time during their disease course, these late effects can become a considerable management and quality-of-life issue. This review will examine the range of late toxicities that can occur from pelvic radiotherapy and explore strategies to prevent and mitigate them.

Impact of low-dose tadalafil on adverse events after low-dose-rate brachytherapy for prostate cancer: A bi-center randomized open-label trial

OBJECTIVE

To study the efficacy of phosphodiesterase-5 inhibitor tadalafil in attenuating adverse events after low-dose-rate brachytherapy for prostate cancer.

METHODS

This was a randomized open-label trial, conducted at two institutions. Prostate cancer patients undergoing low-dose-rate brachytherapy were randomly assigned to receive tadalafil (study group) or tamsulosin (control group). The primary endpoint was International Prostate Symptom Score for subjective evaluation of lower urinary tract symptoms. Uroflowmetry, postvoid residual urine volume, and Sexual Health Inventory for Men score were the secondary endpoints. Each clinical variable was evaluated during a follow-up period of 1 year after low-dose-rate brachytherapy.

RESULTS

A total of 107 patients were enrolled in this study, with a final total of 96 patients analyzed. The mean total International Prostate Symptom Score changes at 1, 3, 6, 9, and 12 months after low-dose-rate brachytherapy were +7.4, +7.1, +4.7, +1.5, and +0.8, respectively, in the tamsulosin group, and +8.5, +9.2, +6.4, +4.1, and +1.6, respectively, in the tadalafil group. There were no statistically significant differences in International Prostate Symptom Score with the exception of the score at 9-month follow-up. Moreover, there were no statistically significant differences in any of the uroflowmetry or postvoid residual urine volume findings. The Sexual Health Inventory for Men score in the tadalafil group was significantly higher than that in the tamsulosin group at 6, 9, and 12 months after low-dose-rate brachytherapy.

CONCLUSIONS

Tadalafil could be an effective option for the management of lower urinary tract symptoms after low-dose-rate brachytherapy.

Role of application of tadalafil 5 mg once-daily (≥6 months) in men with erectile dysfunction from six randomized controlled trials

This meta-analysis was performed to assess the efficacy and safety of taking tadalafil 5 mg once-daily for at least 6 months in the treatment of erectile dysfunction (ED). Based on databases: MEDLINE, EMBASE and Cochrane Controlled Trials Register, this analysis was performed to collect randomized controlled trials (RCTs) of tadalafil 5mg once-daily in treating ED over 6 months. Reviewers also investigated the references of each literature. The meta-analysis covered a total of 1,596 patients in six RCTs. The tadalafil group performed a better effect in terms of the international index of erectile function-erectile function (IIEF) domain (P=0.005) for the treatment of ED compared with the placebo group. Safety assessments including discontinuations due to adverse events (AEs) (P=0.31) and treatment-emergent AEs (P=0.06) indicated that the tadalafil group had a better tolerate. The analysis elucidates that the dose of 5 mg per day of tadalafil showed a good effect after the treatment of at least 6 months relative to the control group with fewer side effects.

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.

Prostatic irradiation-induced sexual dysfunction: A review and multidisciplinary guide to management in the radical radiotherapy era (Part II on Urological Management)

Prostate cancer is the most common malignancy in men and the second leading cause of cancer-related death in men. Radiotherapy is a curative option that is administered via external beam radiation, brachytherapy, or in combination. Sexual dysfunction is a common toxicity following radiotherapy, similar to men undergoing radical prostatectomy, but the etiology is different. The pathophysiology of radiation-induced sexual dysfunction is multi-factorial, and the toxicity is a major cause of impaired quality of life among long-term prostate cancer survivors. Management of a patient's sexual function during and after radiotherapy requires multidisciplinary coordination of care between radiation oncology, urology, psychiatry, pharmacy, and dermatology. This review provides a framework for clinicians to better understand prostatic radiotherapy-induced sexual dysfunction diagnosis, evaluation, and a patient-centered approach to toxicity preventive strategies and management.

Placebo Responses Among Men With Erectile Dysfunction Enrolled in Phosphodiesterase 5 Inhibitor Trials: A Systematic Review and Meta-analysis

IMPORTANCE

Placebo responses in the treatment of erectile dysfunction (ED) are poorly described in the literature to date.

OBJECTIVE

To quantify the association of placebo with ED outcomes among men enrolled in placebo-controlled, phosphodiesterase 5 inhibitor (PDE5I) trials.

DATA SOURCES

For this systematic review and meta-analysis, a database search was conducted to identify double-blind, placebo-controlled studies using PDE5Is for the treatment of ED published from January 1, 1998, to December 31, 2018, within MEDLINE, Embase, Cochrane Library, and Web of Science. Only articles published in the English language were included.

STUDY SELECTION

Double-blind, placebo-controlled randomized clinical trials of PDE5Is for ED were included. Studies were excluded if they did not provide distribution measures for statistical analysis. Study selection review assessments were conducted by 2 independent investigators. A total of 2215 studies were identified from the database search, and after review, 63 studies that included 12 564 men were analyzed.

DATA EXTRACTION AND SYNTHESIS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed in abstracting data and assessing validity. Data were extracted from published reports by 2 independent reviewers. Quality assessment was performed using the Jadad scale. Data were pooled using a random-effects model.

MAIN OUTCOMES AND MEASURES

The main outcome was improvement in the erectile function domain of the International Index of Erectile Function questionnaire in the placebo arm of the included studies. Effect size was reported as bias-corrected standardized mean difference (Hedges g). The hypothesis was formulated before data extraction.

RESULTS

A total of 63 studies that included 12 564 men (mean [SD] age, 55 [7] years; age range, 36-68 years) were included. Erectile function was significantly improved among participants in the placebo arm, with a small to moderate effect size (Hedges g [SE], 0.35 [0.03]; P < .001). Placebo effect size was larger among participants with ED associated with posttraumatic stress disorder (Hedges g [SE], 0.78 [0.32]; P = .02) compared with the overall analysis. No significant difference was found between placebo and PDE5Is for ED after prostate surgery or radiotherapy (Hedges g [SE], 0.30 [0.17]; P = .08).

CONCLUSIONS AND RELEVANCE

In this study, placebo was associated with improvement of ED, especially among men with ED-related posttraumatic stress disorder. No difference was found between placebo and PDE5I among men treated for ED after prostate surgery.

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.

Regulation of PDE5 expression in normal prostate, benign prostatic hyperplasia, and adenocarcinoma

BACKGROUND

Type 5 phosphodiesterase (PDE5) expression in the normal and pathological prostate is controversial.

OBJECTIVES

This study aimed at identifying the cell type/s, if any, expressing PDE5 in human healthy or pathological prostate sections in order to further validate the rationale of PDE5 inhibitor (PDE5i) treatment of benign prostatic hyperplasia (BPH) and their safety in the treatment of erectile dysfunction following prostate cancer (PCa) surgery.

MATERIALS AND METHODS

By immunohistochemical analysis, we studied PDE5 expression in tissue microarrays containing sections obtained from healthy, BPH, and PCa samples.

RESULTS

Our results showed that PDE5 is barely expressed in the epithelial or stromal compartment of normal human prostates, but it is highly expressed in the stromal compartment of BPH sections. We also found that a low but significant number of PCa samples (22%) expressed PDE5 in the epithelial cancer cells but not in stromal cells and that such expression was not correlated with the tumor aggressiveness, according to their Gleason score.

DISCUSSION AND CONCLUSION

PDE5 overexpression in the stromal compartment of BPH samples supports the rationale of PDE5 as a target in lower urinary tract symptoms of BPH. PDE5 expression in a significant percentage of PCa samples but the lack of correlation with the Gleason score suggests that this enzyme is not correlated with tumor aggressiveness; however, a role of PDE5 in the minimal residual disease of PCa cannot be excluded.

Mild hyperthermia as a localized radiosensitizer for deep-seated tumors: investigation in an orthotopic prostate cancer model in mice

OBJECTIVE:

Non-ablative or mild hyperthermia (HT) has been shown in preclinical (and clinical) studies as a localized radiosensitizer that enhances the tumoricidal effects of radiation. Most preclinical in vivo HT studies use subcutaneous tumor models which do not adequately represent clinical conditions (e.g. proximity of normal/critical organs) or replicate the tumor microenvironment-both of which are important factors for eventual clinical translation. The purpose of this work is to demonstrate proof-of-concept of locoregional radiosensitization with superficially applied, radiofrequency (RF)-induced HT in an orthotopic mouse model of prostate cancer.

METHODS:

In a 4-arm study, 40 athymic male nude mice were inoculated in the prostate with luciferase-transfected human prostate cancer cells (PC3). Tumor volumes were allowed to reach 150-250 mm3 (as measured by ultrasound) following which, mice were randomized into (i) control (no intervention); (ii) HT alone; (iii) RT alone; and (iv) HT + RT. RF-induced HT was administered (Groups ii and iv) using the Oncotherm LAB EHY-100 device to achieve a target temperature of 41 °C in the prostate. RT was administered ~30 min following HT, using an image-guided small animal radiotherapy research platform. In each case, a dual arc plan was used to deliver 12 Gy to the target in a single fraction. One animal from each cohort was euthanized on Day 10 or 11 after treatment for caspase-9 and caspase-3 Western blot analysis.

RESULTS:

The inoculation success rate was 89%. Mean tumor size at randomization (~16 days post-inoculation) was ~189 mm3 . Following the administration of RT and HT, mean tumor doubling times in days were: control = 4.2; HT = 4.5; RT = 30.4; and HT + RT = 33.4. A significant difference (p = 0.036) was noted between normalized nadir volumes for the RT alone (0.76) and the HT + RT (0.40) groups. Increased caspase-3 expression was seen in the combination treatment group compared to the other treatment groups.

CONCLUSION:

These early results demonstrate the successful use of external mild HT as a localized radiosensitizer for deep-seated tumors.

ADVANCES IN KNOWLEDGE:

We successfully demonstrated the feasibility of administering external mild HT in an orthotopic tumor model and demonstrated preclinical proof-of-concept of HT-based localized radiosensitization in prostate cancer radiotherapy.

Clarifying the Relative Impacts of Vascular and Nerve Injury That Culminate in Erectile Dysfunction in a Pilot Study Using a Rat Model of Prostate Irradiation and a Thrombopoietin Mimetic

PURPOSE

Radiation therapy (RT) offers an important and curative approach to treating prostate cancer, but it is associated with a high incidence of erectile dysfunction (ED). It is not clear whether the etiology of radiation-induced ED (RI-ED) is driven by RT-mediated injury to the vasculature, the nerves, or both. This pilot study sought to distinguish the effects of vascular and nerve injury in RI-ED by applying a vascular radioprotectant in a rat model of prostate RT.

METHODS

A single dose of the thrombopoietin mimetic (TPOm; RWJ-800088), previously shown to mitigate radiation-induced vascular injury, was administered 10 minutes after single-fraction conformal prostate RT. Nine weeks after RT, rats were assessed for erectile and arterial function. Nerve markers were quantified with reverse transcriptase polymerase chain reaction. Immunofluorescent microscopy further characterized vascular effects of RT and TPOm.

RESULTS

Sham animals and animals that received RT and TPOm showed significant arterial vasodilation in response to systemic hydralazine (24.1% ± 7.3% increase; P = .03 in paired t test). However, animals that received RT and vehicle were unable to mount a vasodilatory response (-7.4% ± 9.9% increase; P = .44 in paired t test). TPOm prevented RT-induced change in the penile artery cross-sectional area (P = .036), but it did not ameliorate cavernous nerve injury as evaluated by gene expression of neuronal injury markers. Despite significant structural and functional vascular protective effects and some trends for differences in nerve injury/recovery markers, TPOm did not prevent RI-ED at 9 weeks, as assessed by intracavernous pressure monitoring after cavernous nerve stimulation.

CONCLUSIONS

These data suggest that vascular protection alone is not sufficient to prevent RI-ED and that cavernous nerve injury plays a key role in RI-ED. Further research is required to delineate the multifactorial nature of RI-ED and to determine if TPOm with modified dosing regimens can mitigate against nerve injury either through direct or vascular protective effects.

Resveratrol treatment may preserve the erectile function after radiotherapy by restoring antioxidant defence mechanisms, SIRT1 and NOS protein expressions

Radiotherapy (RT) for prostate cancer (PC) can cause erectile dysfunction (ED) by damaging neurovascular structures with oxidative stress. In this study, we evaluated the effects of resveratrol, an antioxidant, on post-RT ED. Fifty rats in five groups were evaluated; control (C), prostate-confined radiotherapy with short- and long-term vehicle or resveratrol treatment. Cavernosal tissues were obtained to analyze glutathione (GSH), nitric oxide (NO), cyclic guanosine monophosphate (cGMP), 8-hydroxy-2'-deoxy-guanosine (8-OHdG) levels and superoxide dismutase (SOD), caspase-3 activities, sirtuin-1, Foxo-3, nNOS, and eNOS protein expressions. Intracavernosal pressures (ICP) were measured for the long-term treatment group. In the RT + long-term vehicle treatment group, tissue GSH, NO, cGMP, and SOD activity were decreased while 8-OHdg levels and caspase-3 activities were increased. Radiotherapy caused a decrease in sirtuin-1, nNOS, and eNOS protein expressions. These parameters were reversed by resveratrol treatment. Foxo-3 protein expressions were unaltered in the RT + short-term vehicle treatment group and started to increase as a defense mechanism in the RT + long-term vehicle group; however, resveratrol treatment caused a significant increase in Foxo-3 expressions. Resveratrol preserved the metabolic pathways involved in erectile function and provided functional protection. Resveratrol can be used as a supplementary agent in patients undergoing radiotherapy to preserve erectile function.

A mini-review of quality of life as an outcome in prostate cancer trials: patient-centered approaches are needed to propose appropriate treatments on behalf of patients

Background

Patients with prostate cancer (PC) may be ready to make trade-offs between their quantity and their quality of life. For instance, elderly patients may prefer the absence of treatment if it is associated with a low-risk of disease progression, compared to treatments aiming at preventing disease progression but with a substantial deterioration of their Health-Related Quality of Life (HRQoL). Therefore, it seems relevant to compare the treatments by considering both survival and HRQoL. In this mini-review, the aim was to question whether the potential trade-offs between survival and HRQoL are considered in high impact factor journals.

Methods

The study was conducted from the PubMed database for recent papers published between May 01, 2013, and May 01, 2015. We also restricted our search to nine medical journals with 2013 impact factor > 15.

Results

Among the 30 selected studies, only six collected individual HRQoL as a secondary endpoint by using the Functional Assessment of Cancer Therapy-Prostate (FACT-P) questionnaire. In four studies, the time to HRQoL change was analyzed, but its definitions varied. In two studies, the mean changes in HRQoL between the baseline and the 12- or 16-week follow-up were analyzed. None of the six studies reported in a single endpoint both the quantity and the quality of life.

Conclusions

Our mini-review, which only focused on recent publications in journals with high-impact, suggests moving PC clinical research towards patient-centered outcomes-based studies. This may help physicians to propose the most appropriate treatment on behalf of patients. We recommend the use of indicators such as Quality-Adjusted Life-Years (QALYs) as principal endpoint in future clinical trials.

Electronic supplementary material

The online version of this article (10.1186/s12955-018-0870-6) contains supplementary material, which is available to authorized users.

[Sexual consequences after treatment of prostate cancer: Inquiry among members of the Association Nationale des Malades du Cancer de la Prostate]

INTRODUCTION

Complications of prostate cancer treatments are responsible of a lower quality of life. We evaluated the prevalence and the perceptions of sexual consequences of prostate cancer treatments.

MATERIALS AND METHODS

A retrospective self-administered questionnaire was sent to all the members of the Association Nationale des Malades du Cancer de la Prostate (ANAMACAP). All the answers were analyzed.

RESULTS

226 questionnaires were analyzed, the average age was 67.3 years old, the average follow-up was 58.1 months. 110 patients had surgery only, 29 had hormone therapy plus radiotherapy, 28 had radiation therapy only and 49 had combined treatments. After the treatment of the prostate cancer, an erectile dysfunction was reported by 75.2% of the patients; an orgasmic dysfunction by 69%; a climacturia by 21%; a reduced penile length by 70% of them and a less sensitive glans by 59%. They were responsible of a lower quality of life for 75% to 90% of the patients depending on the symptom. A PDE5-inhibitor treatment was effective for only 25.6% of them when taken daily and for 39% on demand.

CONCLUSION

Functional consequences of prostate cancer treatments are common, diverse and directly involved in the sexual life. It is necessary to improve therapeutical education and onco-sexology with the help of patients' associations, to build a new balance in the couples.

LEVEL OF EVIDENCE

3.

Current Status of Targeted Radioprotection and Radiation Injury Mitigation and Treatment Agents: A Critical Review of the Literature

As more cancer patients survive their disease, concerns about radiation therapy-induced side effects have increased. The concept of radioprotection and radiation injury mitigation and treatment offers the possibility to enhance the therapeutic ratio of radiation therapy by limiting radiation therapy-induced normal tissue injury without compromising its antitumor effect. Advances in the understanding of the underlying mechanisms of radiation toxicity have stimulated radiation oncologists to target these pathways across different organ systems. These generalized radiation injury mechanisms include production of free radicals such as superoxides, activation of inflammatory pathways, and vascular endothelial dysfunction leading to tissue hypoxia. There is a significant body of literature evaluating the effectiveness of various treatments in preventing, mitigating, or treating radiation-induced normal tissue injury. Whereas some reviews have focused on a specific disease site or agent, this critical review focuses on a mechanistic classification of activity and assesses multiple agents across different disease sites. The classification of agents used herein further offers a useful framework to organize the multitude of treatments that have been studied. Many commonly available treatments have demonstrated benefit in prevention, mitigation, and/or treatment of radiation toxicity and warrant further investigation. These drug-based approaches to radioprotection and radiation injury mitigation and treatment represent an important method of making radiation therapy safer.

Penile rehabilitation following prostate cancer treatment: review of current literature

Radical prostatectomy (RP) and radiotherapy (RT) are highly effective in improving prostate cancer survival. However, both have a detrimental effect on erectile function (EF). Penile rehabilitation consists of understanding the mechanisms that cause erectile dysfunction (ED) and utilizing pharmacologic agents, devices or interventions to promote male sexual function. For the past decade, many researchers have pursued to define effective treatment modalities to improve ED after prostate cancer treatment. Despite the understanding of the mechanisms and well-established rationale for postprostate treatment penile rehabilitation, there is still no consensus regarding effective rehabilitation programs. This article reviews a contemporary series of trials that assess penile rehabilitation and explore treatment modalities that might play a role in the future. Published data and trials related to penile rehabilitation after RP and RT were reviewed and presented. Although recent trials have shown that most therapies are well-tolerated and aid in some degree on EF recovery, we currently do not have tangible evidence to recommend an irrefutable penile rehabilitation algorithm. However, advancements in research and technology will ultimately create and refine management options for penile rehabilitation.

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.

Does tadalafil prevent erectile dysfunction in patients undergoing radiation therapy for prostate cancer?

A recently published paper addressed the interesting topic of prevention of erectile dysfunction (ED) with tadalafil, a phosphodiesterase-type 5 inhibitor (PDE5i) in patients undergoing radiation therapy for localized prostate cancer.1 Tadalafil 5 mg or placebo was administered once-daily for 24 weeks in patients undergoing external-beam radiotherapy (EBRT) or brachytherapy (BT) for prostate cancer. This randomized trial did not show superior efficacy of the active drug compared with placebo 4–6 weeks after stopping the study drug. Furthermore, patients younger than 65 years did not respond significantly better than older patients.

Prevention of erectile dysfunction after radiotherapy for prostate cancer

With increasing scrutiny of prostate cancer (PCa) diagnosis and treatment, much attention has been given to the morbidity caused by radical prostatectomy (RP) and/or radiotherapy (RT). One of the most common side-effects of either treatment is erectile dysfunction (ED).1 Approximately, 40% of patients will experience ED after RT for PCa. The post-RT ED causes significant patient dissatisfaction with cancer treatment as well as decrease in patient and partner psychosocial function.2 To address this issue in patients undergoing RT, Pisansky et al.3 conducted a prospective, randomized, double-blinded, placebo-controlled trial to assess the efficacy of a phosphodiesterase enzyme-5 inhibitor (PDE5i), tadalafil, as a preventive measure for patients undergoing RT for PCa and found no difference in erectile function between the control and treatment groups.

Dose painting to treat single-lobe prostate cancer with hypofractionated high-dose radiation using targeted external beam radiation: Is it feasible?

Targeted focal therapy strategies for treating single-lobe prostate cancer are under investigation. In this planning study, we investigate the feasibility of treating a portion of the prostate to full-dose external beam radiation with reduced dose to the opposite lobe, compared with full-dose radiation delivered to the entire gland using hypofractionated radiation. For 10 consecutive patients with low- to intermediate-risk prostate cancer, 2 hypofractionated, single-arc volumetric-modulated arc therapy (VMAT) plans were designed. The first plan (standard hypofractionation regimen [STD]) included the entire prostate gland, treated to 70 Gy delivered in 28 fractions. The second dose painting plan (DP) encompassed the involved lobe treated to 70 Gy delivered in 28 fractions, whereas the opposing, uninvolved lobe received 50.4 Gy in 28 fractions. Mean dose to the opposing neurovascular bundle (NVB) was considerably lower for DP vs STD, with a mean dose of 53.9 vs 72.3 Gy (p < 0.001). Mean penile bulb dose was 18.6 Gy for DP vs 19.2 Gy for STD (p = 0.880). Mean rectal dose was 21.0 Gy for DP vs 22.8 Gy for STD (p = 0.356). Rectum V70 (the volume receiving ≥70 Gy) was 2.01% for DP vs 2.74% for STD (p = 0.328). Bladder V70 was 1.69% for DP vs 2.78% for STD (p = 0.232). Planning target volume (PTV) maximum dose points were 76.5 and 76.3 Gy for DP and STD, respectively (p = 0.760). This study demonstrates the feasibility of using VMAT for partial-lobe prostate radiation in patients with prostate cancer involving 1 lobe. Partial-lobe prostate plans appeared to spare adjacent critical structures including the opposite NVB.

Radiotherapy for high-risk prostate cancer

The combination of radiation treatment and long-term androgen deprivation therapy (ADT) has been shown in multiple clinical trials to prolong overall survival in men with high-risk prostate cancer compared with either treatment alone. New radiation technologies enable the safe delivery of high radiation doses that improve cancer control compared with lower radiation doses. Based on the results of multiple randomized trials, clinical practice guidelines for high-risk prostate cancer recommend total radiation doses of at least 75.6 Gy, with long-term (2-3 years) ADT. Ongoing research into hypofractionated radiation treatment, whole-pelvic radiation, and combinations of radiation with novel hormonal agents could further improve cancer control and survival outcomes for patients with high-risk prostate cancer.

Effect of aging and long-term erectile function after iodine-125 prostate brachytherapy

PURPOSE

To evaluate long-term erectile function (EF) in men treated with iodine-125 prostate brachytherapy (PB) and to determine factors predictive for erectile dysfunction (ED), including natural decline because of aging.

METHODS

Two thousand nine hundred twenty-nine patients (implanted July 1989-June 2012) with baseline EF and greater than 10-month followup (FU) are included. About 78.9% had full and 7.9% had partial EF at baseline. EF was assessed on a physician-reported three-point scale. Poisson regression with generalized estimating equations was used to assess predictors of ED and Kaplan-Meier curves time to ED. The effect of aging was calculated from the declining rate of baseline EF seen in sequential 5-year age cohorts and from the Massachusetts Male Aging Study.

RESULTS

The median age was 66 years and median FU 3.5 years (maximum 14 years). About 1142 patients had more than 5 years of FU, and 43% had received 6 months of androgen deprivation therapy (ADT). Significant drop in EF was seen at 6 weeks after PB, with gradual decline thereafter. EF preservation at 5 years for age younger than 55, 56-59, 60-64, 65-69, and 70 year and older was 82%, 73%, 58%, 39%, and 23%, respectively. Comparisons of the 5-year age-related and treatment-related EF decline show that 50% of the long-term EF decline is related to aging. On univariate and multivariate analyses, age at implant, length of FU, hypertension, diabetes, and use of ADT (all p < 0.01) were significant predictors of ED.

CONCLUSION

More than 80% of young men have EF preserved 5 years after PB. Age, ADT, history of hypertension, and the natural decline in EF have negative impact on long-term EF after PB.

Prostate cancer survivorship care guideline: American Society of Clinical Oncology Clinical Practice Guideline endorsement

PURPOSE

The guideline aims to optimize health and quality of life for the post-treatment prostate cancer survivor by comprehensively addressing components of follow-up care, including health promotion, prostate cancer surveillance, screening for new cancers, long-term and late functional effects of the disease and its treatment, psychosocial issues, and coordination of care between the survivor's primary care physician and prostate cancer specialist.

METHODS

The American Cancer Society (ACS) Prostate Cancer Survivorship Care Guidelines were reviewed for developmental rigor by methodologists. The American Society of Clinical Oncology (ASCO) Endorsement Panel reviewed the content and recommendations, offering modifications and/or qualifying statements when deemed necessary.

RESULTS

The ASCO Endorsement Panel determined that the recommendations from the 2014 ACS Prostate Cancer Survivorship Care Guidelines are clear, thorough, and relevant, despite the limited availability of high-quality evidence to support many of the recommendations. ASCO endorses the ACS Prostate Cancer Survivorship Care Guidelines, with a number of qualifying statements and modifications.

RECOMMENDATIONS

Assess information needs related to prostate cancer, prostate cancer treatment, adverse effects, and other health concerns and provide or refer survivors to appropriate resources. Measure prostate-specific antigen (PSA) level every 6 to 12 months for the first 5 years and then annually, considering more frequent evaluation in men at high risk for recurrence and in candidates for salvage therapy. Refer survivors with elevated or increasing PSA levels back to their primary treating physician for evaluation and management. Adhere to ACS guidelines for the early detection of cancer. Assess and manage physical and psychosocial effects of prostate cancer and its treatment. Annually assess for the presence of long-term or late effects of prostate cancer and its treatment.

Temporal changes in neurotrophic factors and neurite outgrowth in the major pelvic ganglion following cavernous nerve injury

Despite nerve-sparing radical prostatectomy, nerve damage and erectile dysfunction (ED) prevail, and preventing neurodegeneration is of great importance. Neurotrophic factors and neurite outgrowth were characterized in major pelvic ganglia (MPG) following bilateral cavernous nerve injury (BCNI). Young male Sprague-Dawley rats underwent sham or BCNI surgery, and the intracavernosal pressure to mean arterial pressure ratio was measured 2, 7, 14, 21, 30, and 60 days following injury (n = 8/group). MPG gene expression (qPCR) and Western blot were performed for glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF), neurturin, neurotrophin (NT)-3, NT4, brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor, and activating transcription factor 3 (ATF3). Additional rats were injured, and MPGs were removed 24 hr, 48 hr, 3 days, and 7 days following BCNI (n = 3/group). MPGs were cultured in Matrigel, and neurite outgrowth was measured. Erections were impaired early and improved by 60 days in BCNI rats. GDNF, NGF, BDNF, and ATF3 gene expression was significantly increased and NT3 was decreased in MPGs following BCNI (48 hr to 21 days, P < 0.05). GDNF and NGF protein levels were elevated in 48-hr BCNI rats. MPG neurite outgrowth from 24-hr and 48-hr BCNI was higher than sham (658 ± 19 μm, 607 ± 24 μm, 393 ± 23 μm, respectively, P < 0.05). Further studies examining the roles of neurotrophic factors in modulating signaling pathways may provide therapeutic avenues for neurogenically mediated ED.

Penile Rehabilitation Strategies Among Prostate Cancer Survivors

Despite advances in technical and surgical approaches, erectile dysfunction (ED) remains the most common complication among prostate cancer survivors, adversely impacting quality of life. This article analyzes the concept and rationale of ED rehabilitation programs in prostate cancer patients. Emphasis is placed on the pathophysiology of ED after diagnosis and treatment of prostate cancer to understand the efficacy of rehabilitation programs in clinical practice. Available evidence shows that ED is a transient complication following prostate biopsy and cancer diagnosis, with no evidence to support rehabilitation programs in these patients. A small increase in ED and in the use of phosphodiesterase type 5 (PDE5) inhibitors was reported in patients under active surveillance. Patients should be advised that active surveillance is unlikely to severely affect erectile function, but clinically significant changes in sexual function are possible. Focal therapy could be an intermediate option for patients demanding treatment/refusing active surveillance and invested in maintaining sexual activity. Unlike radical prostatectomy, there is no support for PDE5 inhibitor use to prevent ED after highly conformal external radiotherapy or low-dose rate brachytherapy. Despite progress in the understanding of the pathophysiologic mechanisms responsible for ED in prostate cancer patients, the success rates of rehabilitation programs remain low in clinical practice. Alternative strategies to prevent ED appear warranted, with attention toward neuromodulation, nerve grafting, nerve preservation, stem cell therapy, investigation of neuroprotective interventions, and further refinements of radiotherapy dosing and delivery methods.

Progress and controversies: Radiation therapy for prostate cancer

Radiation therapy remains a standard treatment option for men with localized prostate cancer. Alone or in combination with androgen-deprivation therapy, it represents a curative treatment and has been shown to prolong survival in selected populations. In this article, the authors review recent advances in prostate radiation-treatment techniques, photon versus proton radiation, modification of treatment fractionation, and brachytherapy-all focusing on disease control and the impact on morbidity. Also discussed are refinements in the risk stratification of men with prostate cancer and how these are better for matching patients to appropriate treatment, particularly around combined androgen-deprivation therapy. Many of these advances have cost and treatment burden implications, which have significant repercussions given the prevalence of prostate cancer. The discussion includes approaches to improve value and future directions for research.

A systematic review of hypofractionation for primary management of prostate cancer

CONTEXT

Technological advances in radiation therapy delivery have permitted the use of high-dose-per-fraction radiation therapy (RT) for early-stage prostate cancer (PCa). Level 1 evidence supporting the safety and efficacy of hypofractionated RT is evolving as this modality becomes more widely utilized and refined.

OBJECTIVE

To perform a systematic review of the current evidence on the safety and efficacy of hypofractionated RT for early-stage PCa and to provide in-context recommendations for current application of this technology.

EVIDENCE ACQUISITION

Embase, PubMed, and Scopus electronic databases were queried for English-language articles from January 1990 through June 2014. Prospective studies with a minimum of 50 patients were included. Separate consideration was made for studies involving moderate hypofractionation (doses of 2.5-4Gy per fraction) and extreme hypofractionation (5-10Gy in 4-7 fractions).

EVIDENCE SYNTHESIS

Six relatively small superiority designed randomized trials of standard fractionation versus moderate hypofractionation in predominantly low- and intermediate-risk PCa have been published with follow-up ranging from 4 to 8 yr, noting similar biochemical control (5-yr freedom from biochemical failure in modern studies is >80% for low-risk and intermediate-risk patients) and late grade ≥2 genitourinary and gastrointestinal toxicities (between 2% and 20%). Noninferiority studies are pending. In prospective phase 2 studies, extreme hypofractionation has promising 2- to 5-yr biochemical control rates of >90% for low-risk patients. Results from a randomized trial are expected in 2015.

CONCLUSIONS

Moderate hypofractionation has 5-yr data to date establishing safety compared with standard fractionation, but 10-yr outcomes and longer follow-up are needed to establish noninferiority for clinical effectiveness. Extreme hypofractionation is promising but as yet requires reporting of randomized data prior to application outside of a clinical protocol.

PATIENT SUMMARY

Hypofractionation for prostate cancer delivers relatively high doses of radiation per treatment. Prospective studies support the safety of moderate hypofractionation, while extreme fractionation may have greater toxicity. Both show promising cancer control but long-term results of noninferiority studies of both methods are required before use in routine treatment outside of clinical protocols.