Phosphodiesterase Type 5 Inhibitor Use and Disease Recurrence After Prostate Cancer Treatment

Princeton IV consensus guidelines: PDE5 inhibitors and cardiac health

BACKGROUND

In 1999, 1 year after the approval of the first oral phosphodiesterase type 5 (PDE5) inhibitor for the treatment of erectile dysfunction (ED), the first Princeton Consensus Conference was held to address the clinical management of men with ED who also had cardiovascular disease. These issues were readdressed in the second and third conferences. In the 13 years since the last Princeton Consensus Conference, the experience with PDE5 inhibitors is more robust, and recent new data have emerged regarding not only safety and drug-drug interactions, but also a potential cardioprotective effect of these drugs.

AIM

In March 2023, an interdisciplinary group of scientists and practitioners met for the fourth Princeton Consensus Guidelines at the Huntington Medical Research Institutes in Pasadena, California, to readdress the cardiovascular workup of men presenting with ED as well as the approach to treatment of ED in men with known cardiovascular disease.

METHOD

A series of lectures from experts in the field followed by Delphi-type discussions were developed to reach consensus.

OUTCOMES

Consensus was reached regarding a number of issues related to erectile dysfunction and the interaction with cardiovascular health and phosphodiesterase-5 inhibitors.

RESULTS

An algorithm based on recent recommendations of the American College of Cardiology and American Heart Association, including the use of computed tomography coronary artery calcium scoring, was integrated into the evaluation of men presenting with ED. Additionally, the issue of nitrate use was further considered in an algorithm regarding the treatment of ED patients with coronary artery disease. Other topics included the psychological effect of ED and the benefits of treating it; the mechanism of action of the PDE5 inhibitors; drug-drug interactions; optimizing use of a PDE5 inhibitors; rare adverse events; potential cardiovascular benefits observed in recent retrospective studies; adulteration of dietary supplements with PDE5 inhibitors; the pros and cons of over-the-counter PDE5 inhibitors; non-PDE5 inhibitor therapy for ED including restorative therapies such as stem cells, platelet-rich plasma, and shock therapy; other non-PDE5 inhibitor therapies, including injection therapy and penile prostheses; the issue of safety and effectiveness of PDE5 inhibitors in women; and recommendations for future studies in the field of sexual dysfunction and PDE5 inhibitor use were discussed.

CLINICAL IMPLICATIONS

Algorithms and tables were developed to help guide the clinician in dealing with the interaction of ED and cardiovascular risk and disease.

STRENGTHS AND LIMITATIONS

Strengths include the expertise of the participants and consensus recommendations. Limitations included that participants were from the United States only for this particular meeting.

CONCLUSION

The issue of the intersection between cardiovascular health and sexual health remains an important topic with new studies suggesting the cardiovascular safety of PDE5 inhibitors.

Phosphodiesterase-5 Inhibitor Use in Robot Assisted Radical Prostatectomy Patients Is Associated with Reduced Risk of Death: A Propensity Score Matched Analysis of 1,058 Patients

PURPOSE

We investigated whether the use of a phosphodiesterase-5 inhibitor (PDE5i) after robot assited radical prostatectomy has a survival benefit over non-use patients because there are controversial results on the association between PDE5i use and survival outcomes for prostate cancer patients in literature.

MATERIALS AND METHODS

We designed a retrospective, matched, large-sample cohort study of 5,545 patients who underwent robot assisted radical prostatectomy (RARP) during 2013-2021 in a single institute. The exclusion criteria was patients who were aged >70 years at surgery, American Society of Anesthesiologists (ASA) physical status classification grade 4 or 5, history of other malignancies, patients who started PDE5i 6 months after survery and patients with follow up period less than 24 months after surgery. Among the 1,843 included patients, 1,298 were PDE5i users, and 545 were PDE5i non-users. We performed propensity score matching (PSM) of PDE5i users (n=529) with non-users (n=529) by adjusting for the variables of age, Gleason grade group, pathological T stage, preoperative ASA physical status grade, and International Index of Erectile Function score.

RESULTS

There were no significant difference in patient characteristics according to PSM. Kaplan-Meier curve revealed the difference of overall survival for PDE5i users and non-users (clustered log-rank test p<0.05). In a stratified Cox regression analysis, PDE5i use after RARP was associated with improved overall survival and reduced risk of death (hazard ratio 0.43; confidence interval 0.24-0.79; p=0.007). The limitation of this study was that the indication for the prescription of PDE5i was not given.

CONCLUSIONS

PDE5i administration after RARP were associated with overall survival of patients with prostate cancer. A further randomized control trial may reveal whether routine use of PDE5i after prostatectomy can improve survival of prostate cancer patient.

Use of phosphodiesterase-5 inhibitors and the incidence of melanoma

INTRODUCTION

Recent evidence of a causal link between Phosphodiesterase-5-inhibitor (PDE-5i) use and melanoma has caused concern in PDE-5i use and was even addressed in the 2018 American Urological Association guideline on erectile dysfunction (ED). Given that several studies have affirmed this low probability but statistically significant association, one might expect a shift in melanoma diagnoses since PDE-5is were introduced in 1998. We sought to determine if the introduction of PDE-5i drugs for ED treatment increased incidence of melanoma.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to compare the incidence of melanoma diagnosis in American men between 1973 and 2015, providing over a decade of data before and after PDE-5i introduction in 1998. Interrupted time-series and logistic regression were used to assess this relationship.

RESULTS

Over 43 years, the SEER database has reported 292,166 cases of Melanoma, with males accounting for 53.7% of cases (Standard deviation [SD] 3%, Range 47.5-58.3%). After the introduction of PDE-5i, there was no proportional increase in melanoma diagnoses, in fact demonstrating a 2% lower incidence from prediction models (p < 0.05).

CONCLUSION

Our analysis of the SEER database demonstrates that the trend in incidence of melanoma has fallen in the era of PDE-5i use for ED. These findings may be of value in counseling patients anxious about the potential association between PDE-5i use and skin cancer; however, continued research analyzing individual-level risk are needed.

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.

The association of phosphodiesterase-5 inhibitors with the biochemical recurrence-free and overall survival of patients with prostate cancer following radical prostatectomy

PURPOSE

To determine whether phosphodiesterase-5 inhibitor documentation is associated with biochemical relapse-free and overall survival of patients with prostate cancer treated with radical prostatectomy.

MATERIALS AND METHODS

We undertook a retrospective cohort analysis of 3,100 patients with prostate cancer treated with radical prostatectomy between 2003 and 2015. The patients were categorized as a phosphodiesterase- 5- inhibitor user or non-user. The biochemical relapse-free and overall survival at 5-years and 10-years were determined.

RESULTS

Of the patients, 1,372 reported phosphodiesterase-5 inhibitor documentation, and 1,728 did not. The biochemical recurrence-free survival for non-users at 5- and 10-years follow-up was 87.6% and 85.3%, respectively, and the overall survival at these time intervals was 97.9% and 94.5%. The biochemical recurrence-free survival for phosphodiesterase-5 inhibitor users was 94.3% and 93.2% at 5- and 10-years follow-up, respectively, and overall survival was 99.2% and 95.8% at these intervals. The hazard ratio for biochemical recurrence-free survival was 0.44 (CI 0.34-0.56) and for overall survival was 0.65 (CI 0.45-0.94). On the multivariate analysis, phosphodiesterase-5 inhibitor documentation was associated with a lower risk of biochemical recurrence and death when corrected for the other variables. Age at surgery and Gleason scores >8 was associated with a higher risk of death. Higher pathological stage, higher Gleason score, presence of lymph node metastases, and nonwhite race were associated with a higher risk of recurrence.

CONCLUSION

This retrospective analysis revealed a significant association of postoperative phosphodiesterase-5 inhibitor documentation with biochemical recurrence-free- and overall survival in patients with localized prostate cancer treated with radical prostatectomy. Larger scale studies are warranted to investigate the clinical significance of this association.

Prostate Cancer Cell Phenotypes Remain Stable Following PDE5 Inhibition in the Clinically Relevant Range

Widespread cGMP-specific phosphodiesterase 5 (PDE5) inhibitor use in male reproductive health and particularly in prostate cancer patients following surgery has generated interest in how these drugs affect the ability of residual tumor cells to proliferate, migrate, and form recurrent colonies. Prostate cancer cell lines were treated with PDE5 inhibitors at clinically relevant concentrations. Proliferation, colony formation, and migration phenotypes remained stable even when cells were co-treated with a stimulator of cGMP synthesis that facilitated cGMP accumulation upon PDE5 inhibition. Surprisingly, supraclinical concentrations of PDE5 inhibitor counteracted proliferation, colony formation, and migration of prostate cancer cell models. These findings provide tumor cell-autonomous evidence in support of the field's predominant view that PDE5 inhibitors are safe adjuvant agents to promote functional recovery of normal tissue after prostatectomy, but do not rule out potential cancer-promoting effects of PDE5 inhibitors in the more complex environment of the prostate.

Guanylyl Cyclase-cGMP Signaling Pathway in Melanocytes: Differential Effects of Altered Gravity in Non-Metastatic and Metastatic Cells

Human epidermal melanocytes as melanin producing skin cells represent a crucial barrier against UV-radiation and oxidative stress. It was shown that the intracellular signaling molecule cyclic guanosine-3′,5′-monophosphate (cGMP), generated by the guanylyl cyclases (GCs), e.g., the nitric oxide (NO)-sensitive soluble GC (sGC) and the natriuretic peptide-activated particulate GC (GC-A/GC-B), plays a role in the melanocyte response to environmental stress. Importantly, cGMP is involved in NO-induced perturbation of melanocyte–extracellular matrix interactions and in addition, increased NO production during inflammation may lead to loss of melanocytes and support melanoma metastasis. Further, the NO-sensitive sGC is expressed predominantly in human melanocytes and non-metastatic melanoma cells, whereas absence of functional sGC but up-regulated expression of GC-A/GC-B and inducible NO synthase (iNOS) are detected in metastatic cells. Thus, suppression of sGC expression as well as up-regulated expression of GC-A/GC-B/iNOS appears to correlate with tumor aggressiveness. As the cGMP pathway plays important roles in melanocyte (patho)physiology, we present an overview on the differential effects of altered gravity (hypergravity/simulated microgravity) on the cGMP signaling pathway in melanocytes and melanoma cells with different metastatic potential. We believe that future experiments in real microgravity may benefit from considering cGMP signaling as a possible factor for melanocyte transformation and in medication.

Integrative analysis of h-prune as a potential therapeutic target for hepatocellular carcinoma

Background

Drosophila prune protein (h-prune) has been proved to play an essential role in regulating tumor metastasis. However, the clinical relevance of h-prune and its potential mechanism in regulating hepatocellular carcinoma (HCC) are still poorly understood.

Methods

In this study, we used tissue microarrays (TMA) containing 304 HCC tumor samples to evaluate the expression of h-prune and its correlation with prognosis. Data of RNAseq, mutation profiles, copy number variation (CNV), miRNAseq and methylation array from The Cancer Genome Atlas (TCGA) dataset were adopted to analyze the distinctive genomic patterns associated with h-prune expression.

Results

By using TMA, we found increased expression of h-prune in HCC tumor cells compared with adjacent normal tissues. Higher expression of h-prune was correlated with poorer OS and DFS outcomes. In addition, multivariate analysis showed that h-prune expression was an independent risk factor for both OS and DFS. Gene enrichment analysis showed that the gene signatures of cell proliferation, DNA methylation and canonical Wnt signaling pathway were enriched in h-prune-high patients. Notably, somatic mutation analysis demonstrated that higher mutation burden of RB1 and RPS6KA3 could be observed in h-prune-high patients. Moreover, integrative analysis revealed a strong correlation between h-prune expression and epigenetic changes.

Interpretation

This study has highlighted the clinical value of h-prune in predicting the prognosis of HCC patients and its essential role in promoting tumorigenesis of HCC.

Effect of phosphodiesterase type 5 inhibitors on prostate cancer risk and biochemical recurrence after prostate cancer treatment: A systematic review and meta-analysis

Recent studies have examined the impact of phosphodiesterase type 5 inhibitors (PDE5-Is) use on the risk of prostate cancer, and biochemical recurrence (BCR) in prostate cancer patients, but the results were inconsistent. A meta-analysis was conducted to assess the associations with all published studies. Databases (PubMed, Web of Science and MEDLINE) were retrieved to identify relevant studies which explored the impact of PDE5-Is use on the risk of prostate cancer, and BCR in prostate cancer patients. The summary results along with 95% confidence intervals (CIs) were calculated. Nine articles were eligible for the inclusion criteria. The pooled analysis showed that PDE5-Is use was not related to the increased risk of prostate cancer (odds ratio (OR), 0.71; 95% CI, 0.40-1.29). Moreover, PDE5-Is use was not linked to BCR risk in prostate cancer patients with erectile dysfunction (ED) following radical prostatectomy or radiation therapy (relative risk (RR), 1.09; 95% CI, 0.89-1.34). The heterogeneity test suggested moderate heterogeneity across studies. PDE5-Is use does not influence the risk of prostate cancer, and BCR in prostate cancer patients. More well-designed studies are warranted to confirm the findings of our analyses.

Is there a relationship between phosphodiesterase type 5 inhibitors and biochemical recurrence after radical prostatectomy: a systematic review and meta-analysis

PURPOSE

Conduct a systematic review and meta-analysis of studies to evaluate the association between the use of PDE5I and biochemical recurrence (BCR) after radical prostatectomy (RP).

METHODS

We searched Embase (from 1996 to Feb 2018), PubMed (from 1996 to Feb 2018), and Cochrane library (from 1999 to Feb 2018), then manually searched the reference lists of key retrieved articles. Original studies that reported the risk of postoperative BCR for PDE5I users, as compared with non-PDE5I users, were included. Data including the characteristic of participants, the risk of BCR after RP and key criteria of study quality were collected. The pooled relative risks (RRs) were calculated with random-effects model.

RESULTS

A total of 5 cohort studies and 1 case-control study were conducted for data analysis (a total of 17752 participants). Only 1 cohort study reported adjusted RR greater than 1 (range for all derived RRs, 0.7-1.47). The meta-analysis revealed that the PDE5I users had no higher risk of BCR after RP (RR = 1.04, 95% confidence interval [CI], 0.79-1.36). Sensitivity analysis showed that the remaining pooled RR and 95% CI were not changed significantly by omitting each study. In addition, the 5-year BCR rate had no significant difference between PDE5I users and non-PDE5I users.

CONCLUSIONS

Our meta-analysis indicated that PDE5I treatment in men following RP did not increase the risk of BCR. The results preliminarily suggested that the use of PDE5I for erectile dysfunction after RP was oncologically safe. Nevertheless, more large sample cohort studies are needed to validate this conclusion.

Association between phosphodiesterase type 5 inhibitors and prostate cancer: A systematic review

INTRODUCTION

We aim to assess the effect of phosphodiesterase type 5 inhibitors (PDE5I) on prostate cancer risk as well on biochemical recurrence after radical prostatectomy.

METHOD

We performed a research using the following keywords "Phosphodiesterase type 5 inhibitors" and "Prostate cancer". Only trials examining the effect of PDE5I on prostate cancer risk and recurrence after radical prostatectomy were included.

RESULTS

Seventeen preclinical trials and seven clinical trials were included. Preclinical studies demonstrate a pivotal role for PDE5I as a modulator of apoptosis preventing prostate carcinogenesis. The clinical benefit of PDE5I was not demonstrated. PDE5I use was not associated with decreased prostate cancer diagnosis in two retrospective cohort studies. Biochemical recurrence after radical prostatectomy was not lower (nor higher) in patients taking PDE5I in three retrospective case match studies.

CONCLUSION

Based on this review, a change in our practice regarding pharmacological reeducation after radical prostatectomy is not justified.

Phosphodiesterase type 5 inhibitors usage and prostate cancer: a match-paired analysis

Background

To treat erectile dysfunction (ED), phosphodiesterase type 5 inhibitors (PDE5i) are commonly used. However, to date, only a few studies exist evaluate a possible effect on the incidence of prostate cancer. One such study completed by the authors’ institution suggested men who use PDE5i for ED may have a lower incidence of prostate cancer. This study was meant to address some of the shortcomings of the former study and further characterize the link between prostate cancer and PDE5i use.

Methods

A retrospective, match-paired analysis was undertaken: 5,717 patients were identified between 2000 and 2011; a 1:2 match pair analysis ultimately identified 394 cases with cancer and 788 controls without cancer. Pairs were matched based on age, ethnicity, and PSA value.

Results

No correlation existed between PDE5i use and prostate cancer [OR 1.02, 95% confidence interval (CI): 0.78–1.35, P=0.8842] or diabetes mellitus and prostate cancer (OR 1.12, 95% CI: 0.84–1.48, P=0.4499). A statistically significant correlation was demonstrated with PSA and prostate cancer (OR 1.48, 95% CI: 1.38–1.58, P<0.0001).

Conclusions

The data suggest that there is essentially no association with PDE5i use and prostate cancer.

Update on the Safety of Phosphodiesterase Type 5 Inhibitors for the Treatment of Erectile Dysfunction

INTRODUCTION

Phosphodiesterase type 5 inhibitors (PDE5Is) have demonstrated efficacy in the treatment of erectile dysfunction (ED). Although historically found to have limited drug-related adverse events, emerging data have suggested that PDE5Is might be associated with melanoma or recurrence of prostate cancer after radical prostatectomy.

AIM

To summarize the literature on the safety of PDE5Is.

METHODS

A literature review was performed through PubMed from 1990 through 2016 regarding ED. Keywords used for the search were erectile dysfunction, phosphodiesterase type 5 inhibitors, sildenafil, vardenafil, tadalafil, avanafil, safety, side effects, and adverse events, among others.

MAIN OUTCOME MEASURES

Visual, auditory, cardiovascular, renal, hepatic, priapic, and oncologic outcomes associated with the intake of PDE5Is for the treatment of ED, in addition to drug interactions, abuse, overdose, and the phenomenon of counterfeit medications.

RESULTS

PDE5Is are safe drugs for the management of ED. Although recent studies have shown an increased risk of non-arteritic ischemic optic neuropathy with PDE5Is, the magnitude of that risk is small. The possibility that PDE5Is cause sensorineural hearing loss remains uncertain. PDE5Is display a safe cardiovascular profile if used according to the Princeton III Consensus guidelines. There appears to be an association between PDE5I use and melanoma but the absence of a mechanism of causation raises doubt that the association is cause and effect. PDE5Is do not increase the risk of biochemical recurrence after prostate cancer management. PDE5I abuse and use of counterfeit medications present serious global health concerns.

CONCLUSION

Current data strongly support the efficacy, tolerability, and overall safety of PDE5Is for the treatment of ED. PDE5Is probably cause a small increase in the risk of non-arteritic ischemic optic neuropathy. Evidence on increased rates of melanoma and prostate cancer recurrence is weak and controversial. PDE5Is should still be considered first-line therapy for the treatment of most etiologies of ED. Yafi FA, Sharlip ID, Becher EF. Update on the Safety of Phosphodiesterase Type 5 Inhibitors for the Treatment of Erectile Dysfunction. Sex Med Rev 2018;6:242-252.

The Association between Phosphodiesterase Type 5 Inhibitors and Prostate Cancer: Results from the REDUCE Study

PURPOSE

Despite routine use of phosphodiesterase type 5 inhibitor to treat erectile dysfunction the role in prostate cancer chemoprevention remains unclear. Only a few studies have explored the link between phosphodiesterase type 5 inhibitor use and prostate cancer. We tested the association between phosphodiesterase type 5 inhibitor and prostate cancer risk in the REDUCE (Reduction by Dutasteride of Prostate Cancer Events) trial.

MATERIALS AND METHODS

REDUCE was a 4-year multicenter study testing the effect of daily dutasteride on prostate cancer risk in men with prostate specific antigen 2.5 to 10.0 ng/ml and negative biopsy who underwent study mandated biopsies at 2 and 4 years. The association of phosphodiesterase type 5 inhibitor with overall prostate cancer risk and disease grade (Gleason 2-6 and 7-10) was examined using adjusted logistic and multinomial regression analysis. Secondary analysis was performed to explore the association between phosphodiesterase type 5 inhibitor and prostate cancer risk in North American men, given the significantly higher use of phosphodiesterase type 5 inhibitor in these subjects.

RESULTS

Phosphodiesterase type 5 inhibitor was not associated with prostate cancer diagnosis (OR 0.90, 95% CI 0.68-1.20, p = 0.476), low grade disease (OR 0.93, 95% CI 0.67-1.27, p = 0.632) or high grade disease (OR 0.85, 95% CI 0.51-1.39, p = 0.508). An inverse trend was seen between phosphodiesterase type 5 inhibitor and prostate cancer diagnosis in North American men but this was not statistically significant (OR 0.67, 95% CI 0.42-1.07, p = 0.091).

CONCLUSIONS

Phosphodiesterase type 5 inhibitor use was not associated with decreased prostate cancer diagnoses on post-hoc analysis of REDUCE. In North American men, who had much higher baseline use of phosphodiesterase type 5 inhibitor, this treatment was associated with an inverse trend of prostate cancer diagnosis that approached but did not reach statistical significance.