Results of vardenafil mediated power Doppler ultrasound, contrast enhanced ultrasound and systematic random biopsies to detect prostate cancer

PDE5 inhibitors and male reproduction: Is there a place for PDE5 inhibitors in infertility clinics or andrology laboratories?

The objective of this review study is to evaluate the therapeutic role of PDE5 inhibitors (PDE5is) in the amelioration of oligoasthenospermia in infertile males. PDE5is have a beneficial influence on the secretory function of the Leydig and Sertoli cells, the biochemical environment within the seminiferous tubule, the contractility of the testicular tunica albuginea, and the prostatic secretory function. In several studies, the overall effect of sildenafil and vardenafil increased quantitative and qualitative sperm motility. Furthermore, some studies indicate that PDE5is influence positively the sperm capacity to undergo capacitation under biochemical conditions that are known to induce the sperm capacitation process. Additional research efforts are necessary in order to recommend unequivocally the usage of sildenafil, vardenafil, or avanafil for the alleviation of male infertility.

The effect of pharmacotherapy on prostate volume, prostate perfusion and prostate-specific antigen (prostate morphometric parameters) in patients with lower urinary tract symptoms and benign prostatic obstruction. A systematic review and meta-analysis

Introduction

The clinical effect of pharmacotherapy on prostate morphometric parameters is largely unknown. The sole exception is 5α-reductase inhibitors (5-ARI) that reduce prostate volume and prostate-specific antigen (PSA). This review assesses the effect of pharmacotherapy on prostate parameters effect on prostate parameters, namely total prostate volume (TPV), transitional zone volume (TZV), PSA and prostate perfusion.

Material and methods

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) reporting on morphometric parameters’ changes after pharmacotherapy, as primary or secondary outcomes. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. RCTs’ quality was assessed by the Cochrane tool and the criteria of the Agency for Healthcare Research and Quality. The effect magnitude was expressed as standard mean difference (SMD). The study protocol was published on PROSPERO (CRD42020170172).

Results

Sixty-seven RCTs were included in the review and 18 in the meta-analysis. The changes after alpha-blockers are comparable to placebo. Long-term studies reporting significant changes from baseline, result from physiologic growth. Finasteride and dutasteride demonstrated large effect sizes in TPV reduction ([SMD]: -1.15 (95% CI: -1.26 to -1.04, p <0.001, and [SMD]:-0.66 (95% CI: -0.83 to -0.49, p <0.001, respectively), and similar PSA reductions. Dutasteride’s effect appears earlier (1^st vs 3^rd month), the changes reach a maximum at month 12 and are sustained thereafter. Phosphodiesterase-5 (PDE-5) inhibitors have no effect on morphometric parameters. Phytotherapy’s effect on TPV is non-significant [SMD]: 0.12 (95% CI: -0.03 to 0.27, p = 0.13). Atorvastatin reduces TPV as compared to placebo (-11.7% vs +2.5%, p <0.01). Co-administration of testosterone with dutasteride spares the prostate from the androgenic stimulation as both TPV and PSA are reduced significantly.

Conclusions

The 5-ARIs show large effect size in reducing TPV and PSA. Tamsulosin improves perfusion but no other effect is evident. PDE-5 inhibitors and phytotherapy do not affect morphometric parameters. Atorvastatin reduces TPV and PSA as opposed to testosterone supplementation.

Phosphodiesterase type 5 inhibitor attenuates chronic ischemia-induced prostatic hyperplasia in a rat model

BACKGROUND

Many elderly men suffer from benign prostatic hyperplasia (BPH). Recently, chronic ischemia in the prostate has been suggested to be related to BPH. Thus, the impact of chronic ischemia on the development of prostatic hyperplasia and the efficacy of phosphodiesterase type 5 (PDE5) inhibitor for hyperplasia were evaluated in a rat model with chronic ischemia induced by local atherosclerosis.

METHODS

Eighteen male Sprague-Dawley rats were divided into three groups: sham operation, regular diet, placebo (SRP); arterial endothelial injury, high cholesterol diet, placebo (AHP); or arterial endothelial injury, high cholesterol diet, and tadalafil as a PDE5 inhibitor (AHT). The endothelial injury in the common iliac arteries was performed using a 2-Fr Fogarty arterial embolectomy catheter through an incision in the femoral artery into the common iliac artery. Diet and oral drugs were administrated for 8 weeks after surgery. At 8 weeks, blood flow to the ventral prostate (VP) was measured using laser speckle blood flow analysis, and the VP was histologically evaluated.

RESULTS

In the AHP group, prostatic blood flow was reduced, and mean VP weight and the interstitial area were significantly enlarged compared with the SRP group. In the AHT group, tadalafil administration obviously ameliorated the reduction of prostatic blood flow relative to the AHP group. Importantly, mean VP weight and the morphological changes in the AHT group were significantly smaller than those in the AHP group.

CONCLUSIONS

Enlargement of the VP resulted from chronic ischemia induced by local arteriosclerosis. Also, administration of tadalafil attenuated VP enlargement. Chronic ischemia in the prostate might thus contribute to the development of BPH, and PDE5 inhibitors might provide an innovative approach to preventing BPH.

Lower urinary tract symptoms/benign prostatic hypertrophy and vascular function: Role of the nitric oxide-phosphodiesterase type 5-cyclic guanosine 3',5'-monophosphate pathway

It is well known that there is an association of lower urinary tract symptoms/benign prostatic hypertrophy with cardiovascular disease, suggesting that lower urinary tract symptoms/benign prostatic hypertrophy is a risk factor for cardiovascular events. Vascular function, including endothelial function and vascular smooth muscle function, is involved in the pathogenesis, maintenance and development of atherosclerosis, leading to cardiovascular events. Vascular dysfunction per se should also contribute to lower urinary tract symptoms/benign prostatic hypertrophy. Both lower urinary tract symptoms/benign prostatic hypertrophy and vascular dysfunction have cardiovascular risk factors, such as hypertension, dyslipidemia, diabetes mellitus, aging, obesity and smoking. Inactivation of the phosphodiesterase type 5-cyclic guanosine 3',5'-monophosphate-nitric oxide pathway causes lower urinary tract symptoms/benign prostatic hypertrophy through an enhancement of sympathetic nervous activity, endothelial dysfunction, increase in Rho-associated kinase activity and vasoconstriction, and decrease in blood flow of pelvic viscera. Both endogenous nitric oxide and exogenous nitric oxide act as vasodilators on vascular smooth muscle cells through an increase in the content of cyclic guanosine 3',5'-monophosphate, which is inactivated by phosphodiesterase type 5. In a clinical setting, phosphodiesterase type 5 inhibitors are widely used in patients with lower urinary tract symptoms/benign prostatic hypertrophy. Phosphodiesterase type 5 inhibitors might have beneficial effects on vascular function through not only inhibition of cyclic guanosine 3',5'-monophosphate degradation, but also increases in testosterone levels and nitric oxide bioavailability, increase in the number and improvement of the function of endothelial progenitor cells, and decrease in insulin resistance. In the present review, the relationships between lower urinary tract symptoms/benign prostatic hypertrophy, the phosphodiesterase type 5-nitric oxide-cyclic guanosine 3',5'-monophosphate pathway, vascular function and cardiovascular outcomes are examined.

Tadalafil for lower urinary tract symptoms secondary to benign prostatic hyperplasia: a review of clinical data in Asian men and an update on the mechanism of action

Tadalafil, a phosphodiesterase type 5 (PDE5) inhibitor, is approved worldwide for the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia (BPH-LUTS). The purpose of this narrative review is to summarize the clinical data on tadalafil 5 mg once-daily, primarily focusing on Asian men with BPH-LUTS, and to update the current understanding of the mechanism of action underlying PDE5 inhibition. Findings from studies have demonstrated that PDE5 is highly expressed in the lower urinary tract and supporting vasculature, and that PDE5 inhibition potentially decreases smooth muscle cell proliferation in the prostate, relaxes smooth muscle in the prostate, bladder neck and supporting vasculature, increases blood perfusion to the lower urinary tract, and modulates bladder afferent nerve activity. A total of 11 larger, 12-week, double-blind, randomized, placebo-controlled studies of tadalafil, including four Asian studies, have been conducted globally, enrolling >3000 men with BPH-LUTS. In addition, two long-term (42- and 52-week) studies enrolled 394 Japanese and 428 North American men, respectively, with BPH-LUTS. Overall, tadalafil 5 mg once-daily resulted in significant improvements in the change from baseline to endpoint in total International Prostate Symptom Scores (IPSS), IPSS storage and voiding subscores, and IPSS quality of life index compared with placebo. Tadalafil was well tolerated and had a favorable safety profile. These findings support tadalafil 5 mg once-daily for treating men, including Asian men, with BPH-LUTS.

Diagnostic performance of contrast enhanced ultrasound in patients with prostate cancer: a meta-analysis

RATIONALE AND OBJECTIVES

We aimed to do a meta-analysis of the existing literature to assess the accuracy of prostate cancer (PCa) studies that use contrast-enhanced ultrasound (CEUS) as a diagnostic tool.

MATERIALS AND METHODS

The MEDLINE, EMBASE, and Cochrane Library databases were searched for relevant original articles published up to August 2012. Characteristics of Included studies were recorded. Methodological quality was assessed by using the quality assessment of diagnostic studies tool. Pooled weighted estimates of diagnostic odds ratio (DOR), sensitivity, specificity, and positive and negative likelihood ratio (LR) were calculated. A summary receiver operator characteristic (SROC) curve was constructed to calculate the area under the curve (AUC). Publication bias analysis was also performed.

RESULTS

Sixteen studies (2624 patients) were included in the meta-analysis. Various contrast agents and imaging modes were applied. The independent random-effects summary showed a variation in diagnostic values. The summary estimates of sensitivity, specificity, and DOR were 0.70, 0.74, and 9.09, respectively. The weighted positive and negative LR were 2.81 and 0.35, with statistically significant between-study heterogeneity (P < .001). Sensitivity was better in positive patient studies than positive biopsy cores ones (0.78 vs. 0.64). SROC plot displayed value for AUC (0.82). Begg's test (P = .822) and Egger's test (P = .198) did not show evidence of publication bias.

CONCLUSION

CEUS is a promising tool in the detection of PCa, but it cannot completely replace systematic biopsy under the present circumstances. It is necessary to standardize imaging techniques, contrast agents and diagnostic criteria. Large samples, multi-center studies and high-quality prospective trials are necessary to assess its clinical value.

Image guidance in the focal treatment of prostate cancer

PURPOSE OF REVIEW

The advent of prostate-specific antigen screening has led to a seven-fold increase in the incidence of prostate cancer without a resultant decrease in mortality rate. This has led to the belief that urologists are overdetecting and overtreating clinically insignificant disease. To maintain the delicate balance between high cancer cure rate and overtreatment, which could potentially lead to unnecessary morbidities, focal therapy has emerged as the reasonable middle ground. In this article, we present the conceptual basis and the challenges of focal therapy, while emphasizing the critical role of imaging in focal treatment of prostate cancer.

RECENT FINDINGS

Multiple phase I trials have demonstrated the feasibility, short-term efficacy, and safety of focal therapy. Fundamental to the success of these trials and the ultimate acceptance of focal therapy is the integral role of imaging in optimal patient selection. Among the different imaging modalities, only ultrasound and multiparametric MRI are intimately involved in the detection, diagnosis, staging, and treatment of prostate cancer. Each modality has its own unique advantages and shortcomings. Recent advances in enhanced ultrasound modalities, functional MRIs, and biopsy platforms have taken focal therapy one step closer to becoming the standard of care.

SUMMARY

Although early results of phase I focal therapy trials are encouraging, long-term oncological outcomes remain to be elucidated. Incorporation of these technological advances into large prospective trials is needed to establish focal therapy as an important asset in the urologist's armamentarium against prostate cancer.

Current status of transrectal ultrasound techniques in prostate cancer

PURPOSE OF REVIEW

Present the current status of transrectal ultrasound imaging in prostate cancer (PCa) and discuss the latest techniques now under preclinical evaluation.

RECENT FINDINGS

Three-dimensional ultrasound and quantification techniques are superior to two-dimensional ultrasound in visualizing PCa and can be beneficial in staging prior to operation. Doppler-guided biopsies are more likely to yield positive results, especially when high Gleason scores are present. Furthermore, Vardenafil usage strengthens Doppler enhancement and can help in increasing the diagnostic accuracy of Doppler. Multiple studies show elastography to be a promising new addition to the ultrasound investigations for detection of PCa. Especially the recently introduced Shear Wave Elastography shows decreased user dependency and increased PCa detection rates. MRI can also aid in the diagnostics of PCa. However, MRI-guided biopsies are more complicated compared to ultrasound guidance. MRI/ultrasound fusion combines best of both techniques and, although just recently emerged, the studies available show promising PCa detection rates.

SUMMARY

Technical improvements in classical ultrasound modalities (2D/3D-greyscale, Doppler) and new modalities (elastography/MRI/ultrasound fusion) raised the accuracy of PCa detection. Especially latest elastography and MRI/ultrasound fusion are showing promising results in PCa visualization.