A review of inflammation and fibrosis: implications for the pathogenesis of Peyronie's disease

Unveiling the molecular Hallmarks of Peyronie's disease: a comprehensive narrative review

Peyronie's disease, a fibroinflammatory disorder, detrimentally impacts the sexual well-being of men and their partners. The manifestation of fibrotic plaques within penile tissue, attributed to dysregulated fibrogenesis, is pathognomonic for this condition. The onset of fibrosis hinges on the perturbation of the equilibrium between matrix metalloproteinases (MMPs), crucial enzymes governing the extracellular matrix, and tissue inhibitors of MMPs (TIMPs). In the context of Peyronie's disease, there is an elevation in TIMP levels coupled with a decline in MMP levels, culminating in fibrogenesis. Despite the scant molecular insights into fibrotic pathologies, particularly in the context of Peyronie's disease, a comprehensive literature search spanning 1995 to 2023, utilizing PubMed Library, was conducted to elucidate these mechanisms. The findings underscore the involvement of growth factors such as FGF and PDGF, and cytokines like IL-1 and IL-6, alongside PAI-1, PTX-3, HIF, and IgG4 in the fibrotic cascade. Given the tissue-specific modulation of fibrosis, comprehending the molecular underpinnings of penile fibrosis becomes imperative for the innovation of novel and efficacious therapies targeting Peyronie's disease. This review stands as a valuable resource for researchers and clinicians engaged in investigating the molecular basis of fibrotic diseases, offering guidance for advancements in understanding Peyronie's disease.

[New "conservative" treatments for Peyronie's disease-real alternatives or expensive pastime?]

Conservative treatment of Peyronie's disease (induratio penis plastica, IPP) remains largely unsuccessful despite decades of research, as the exact disease pathogenesis remains unclear. Currently, IPP is understood as a benign, localized, progressive connective tissue disorder of the tunica albuginea, in which repetitive microtrauma triggers an inflammatory process leading to fibrosis formation. The new "conservative" treatment approaches focus on immune-modulatory and regenerative mechanisms, but significant therapeutic success is still lacking. Treatments such as extracorporeal shockwave therapy, platelet-rich plasma (PRP), stem cell therapy, hyaluronic acid, and botulinum toxin are promising theoretical approaches, but their efficacy is often contradictory and they remain disputed and inadequately supported by studies. Research on these therapeutic approaches is often limited by extremely high costs and the regulations for clinical studies according to the Medicines Act, albeit necessary to further evaluate their effectiveness.

The Promise of Artificial Intelligence in Peyronie's Disease

PURPOSE OF REVIEW

The application of artificial intelligence (AI) to enhance clinical decision-making in Peyronie's disease (PD) has generated significant interest. This review explores the current landscape of AI in PD evaluation.

RECENT FINDINGS

Recent advances in 3D modeling offer a more sophisticated approach to assessing PD deformities; however, the implementation of 3D modeling in clinical practice faces challenges, including the need for specialized equipment and time-consuming data processing, sometimes taking several hours of labor. AI holds promise for overcoming these hurdles through its ability to efficiently process large volumes of data and to perform accurate predictions based on such data. Future integration of AI with 3D modeling techniques could revolutionize PD evaluation by improving patient counseling, surgical planning, and clinical decision-making. Significant gaps in the literature have yet to be addressed, including the absence of robust evidence that incorporating such technology is superior to standard diagnostics.

The prevalence and topographic distribution of penile calcification in a large cohort: a retrospective cross-sectional study

The prevalence of penile calcification in the population remains uncertain. This retrospective multicenter study aimed to determine the prevalence and characteristics of penile calcification in a large cohort of male patients undergoing non-contrast pelvic tomography. A total of 14 545 scans obtained from 19 participating centers between 2016 and 2022 were retrospectively analyzed within a 3-months period. Eligible scans (n = 12 709) were included in the analysis. Patient age, penile imaging status, presence of calcified plaque, and plaque measurements were recorded. Statistical analysis was performed to assess the relationships between calcified plaque, patient age, plaque characteristics, and plaque location. Among the analyzed scans, 767 (6.04%) patients were found to have at least one calcified plaque. Patients with calcified plaque had a significantly higher median age (64 years (IQR 56-72)) compared to those with normal penile evaluation (49 years (IQR 36-60) (p < 0.001). Of the patients with calcified plaque, 46.4% had only one plaque, while 53.6% had multiple plaques. There was a positive correlation between age and the number of plaques (r = 0.31, p < 0.001). The average dimensions of the calcified plaques were as follows: width: 3.9 ± 5 mm, length: 5.3 ± 5.2 mm, height: 3.5 ± 3.2 mm, with an average plaque area of 29 ± 165 mm² and mean plaque volume of 269 ± 3187 mm³. Plaques were predominantly located in the proximal and mid-penile regions (44.1% and 40.5%, respectively), with 77.7% located on the dorsal side of the penis. The hardness level of plaques, assessed by Hounsfield units, median of 362 (IQR 250-487) (range: 100-1400). Patients with multiple plaques had significantly higher Hounsfield unit values compared to those with a single plaque (p = 0.003). Our study revealed that patients with calcified plaques are older and have multiple plaques predominantly located on the dorsal and proximal side of the penis.

Collagenase Clostridium histolyticum for Peyronie's disease: a contemporary atlas of complications and their management

INTRODUCTION

Collagenase Clostridium histolyticum (CCH) remains the only Food and Drug Administration-approved medical treatment for Peyronie's disease (PD). The initial IMPRESS I and II trials (Investigation for Maximal Peyronie's Reduction Efficacy and Safety), which led to Food and Drug Administration approval, revealed a rate of treatment-related adverse events as high as 84%. Studies fail to provide clear definitions of complications.

OBJECTIVES

To review complications, provide a CCH complication atlas, and propose management strategies for commonly encountered complications.

METHODS

We performed a literature review using PubMed. A photographic atlas was provided regarding complications in patients in a high-volume CCH center for PD.

RESULTS

Complications were identified and classified by nature and severity. We followed a standardized previously published grading system for hematomas. Complications include bruising, swelling, hematoma formation, back pain, and, rarely, corporal rupture. Complications were discussed, and hematomas were graded by penile surface area. Complication photographs were graded and displayed. Treatment-related adverse effects do not affect overall results.

CONCLUSION

Recognizing and grading complications associated with CCH therapy for PD is crucial for effective patient management and informed decision making. A standardized grading system allows for consistency in reporting and comparing hematoma complication rates across studies and patient populations. Herein we provide images that will help clinicians identify and confidently manage common complications that may occur in any CCH program.

Research advances in Peyronie's disease: a comprehensive review on genomics, pathways, phenotypic manifestation, and therapeutic targets

INTRODUCTION

Penile induration disease, commonly known as Peyronie's disease (PD), is a connective tissue disorder that affects the penis, leading to the development of fibrous plaques, penile curvature, and erectile dysfunction. PD is a common male reproductive system disease with a complex etiology involving multiple genes, signaling pathways, and different phenotypes.

OBJECTIVES

The etiology and pathogenesis of PD remain poorly understood, hindering the development of effective treatment strategies. By understanding the underlying mechanisms of PD, we can pave the way for targeted therapies and improved patient outcomes.

METHODS

We reviewed the epidemiology and pathophysiology of PD. We performed database searches on Google Scholar, PubMed, Medline, and Web of Science from inception to September 2023. The literature reviewed included priapism guidelines, review articles, current trial studies, and various literature related to PD.

RESULTS

This article provides a comprehensive overview of the current research progress on the disease, focusing on its genetic factors, signaling pathways, cellular mechanisms, phenotypic manifestations, and therapeutic targets. It can help identify individuals at higher risk, aid in early detection and intervention, and provide insights into fibrosis and tissue remodeling. It can also reveal potential therapeutic targets, guide accurate diagnoses and treatment strategies, and address the impact of the disease on patients' quality of life.

CONCLUSION

By integrating insights from genomics, molecular pathways, clinical phenotypes, and therapeutic potentials, our research aims to achieve a deeper and more comprehensive understanding of PD, propelling the field toward innovative strategies that enhance the lives of those affected by PD. The complex manifestations and pathogenesis of PD necessitate the use of multiple treatment methods for personalized care.

Scrotal approach for tunica expansion procedure (TEP) for penile girth and length restoration during penile prosthesis implantation in patients with penile angulation due to Peyronie's disease and erectile dysfunction: technique and outcomes

Peyronie's disease is often comorbid with erectile dysfunction and can cause significant penile shortening. We describe our modified tunica expansion procedure (TEP) technique of penile length preservation and girth enhancement with correction of penile angulation in patients with mild Peyronie's disease (<30 degree angulation, or hourglass deformity, no hinging) and erectile dysfunction presenting for inflatable penile prosthesis (IPP) surgery. A retrospective review of IPP placement from one high volume surgeon was performed. A total of 474 patients' charts from June 2017 to June 2021 were reviewed and those charts of patients undergoing modified TEP in the setting of Peyronie's disease were analyzed. Average increase in length and girth were measured and means with standard deviations calculated. The modified TEP is performed through a scrotal approach and involves complete eversion of the penis with dissection of Buck's fascia off the underlying tunica. Subsequently, staggered scorings of the underlying tunica are performed allowing for circumferential girth enhancement and length preservation. In men with Peyronie's disease, these scorings are preferentially concentrated on the side of the plaque to allow straightening without loss of length. A total of 32 patients with Peyronie's disease from the larger cohort underwent the modified TEP. Mean increase in length of distal corpora was 2.8 ± 0.8 cm (range 2.0-3.4 cm) (measured using Furlow before and after penile eversion with TEP), while mean increase in girth (measured at midphallus prior to prosthesis insertion and after IPP inflation) was 1.6 ± 0.4 cm (range 1.2-2.2 cm). There were no reported complications. A scrotal approach to TEP is an easy to perform technique that can be used to restore length and enhance girth in men with Peyronie's disease undergoing insertion of IPP. Additionally, it is a customizable approach that can also be used to correct mild penile angulation.

The pathogenic role of the immune system in erectile dysfunction and Peyronie's disease: focusing on immunopathophysiology and potential therapeutic strategies

INTRODUCTION

Erectile dysfunction (ED) represents the major cause of male sexual dysfunction, which is often associated with obesity, diabetes mellitus, atherosclerotic cardiovascular disease, and cigarette smoking. Peyronie's disease is a chronic disorder associated with irreversible fibrotic damage of the tunica albuginea leading to ED, painful erection, coital disturbance, and physical and social complaints. Both conditions are characterized by chronic inflammation, oxidative stress, and significant changes in intracavernous hydrodynamics. In this scenario, oxidized lipoproteins, M1-polarized macrophages, proinflammatory cytokines (such as the tumor necrosis factor α), endothelial nitric oxide synthase, penile smooth muscle cells, and toll-like receptors represent the main triggers of the inflammatory process in ED. Phosphodiesterase-5 inhibitors are the most common treatment for ED. This treatment is used intermittently, as it is conceived as a symptomatic and not curative therapy. Moreover, not all patients respond to phosphodiesterase-5 inhibitors (35%-85%), particularly those with dysmetabolic phenotypes. Additional or alternative treatments are therefore desirable, mostly in refractory cases.

OBJECTIVES

In this review, we describe the immune-mediated pathogenesis of ED and Peyronie's disease (PD). In our literature search we placed particular emphasis on potentially practical therapeutic approaches, including natural products (such as polyphenols), due to their anti-inflammatory and antioxidant activities, stem cell therapy, and platelet-derived preparations.

METHODS

We searched PubMed/MEDLINE, Web of Science, Scopus, Cochrane Library, Google Scholar, and institutional websites. Original studies, narrative reviews, systematic reviews, and meta-analyses written in English were searched, screened, and selected.

RESULTS

In animal models of ED and PD, therapeutic approaches, including anti-inflammatory and antioxidant agents, stem cell therapy, and platelet-derived preparations, have provided positive results, including improved penile function, reduced inflammation and oxidative stress, and promotion of tissue repair. However, clinical evidence of improvement in human patients is still insufficient.

CONCLUSION

Promising results for treating ED and PD have been shown in preclinical and pilot clinical studies, but specific clinical trials are needed to validate the efficacy of these therapeutic approaches in men with ED.

[Current treatment concepts for Peyronie's disease]

Plastic induration of the penis (PIP, Peyronie's disease) is an acquired and chronic disease of the penis, which is characterized by penile pain, distortion and deformation of the penis as well as the resulting impairments in sexual activity of the patient. The most probable causes are microtrauma and macrotrauma within the tunica albuginea of the corpora cavernosa, which due to an abnormal wound healing subsequently leads to the formation of fibrosis in this region. Various predisposing factors and also a genetic predisposition are discussed. The PIP occurs most frequently in the fifth to sixth decades of life. The prevalence is 0.3-20% depending on the investigated collective and the risk factors present. The PIP is subdivided into an acute inflammatory phase and a chronic postinflammatory phase. Various conservative and surgical treatment options include oral medication, penile traction therapy, intralesional injections and surgical procedures.

Molecular Mechanisms and Risk Factors Related to the Pathogenesis of Peyronie's Disease

Peyronie's disease (PD) is a benign condition caused by plaque formation on the tunica albuginea of the penis. It is associated with penile pain, curvature, and shortening, and contributes to erectile dysfunction, which worsens patient quality of life. In recent years, research into understanding of the detailed mechanisms and risk factors involved in the development of PD has been increasing. In this review, the pathological mechanisms and several closely related signaling pathways, including TGF-β, WNT/β-catenin, Hedgehog, YAP/TAZ, MAPK, ROCK, and PI3K/AKT, are described. Findings regarding cross-talk among these pathways are then discussed to elucidate the complicated cascade behind tunica albuginea fibrosis. Finally, various risk factors including the genes involved in the development of PD are presented and their association with the disease summarized. The purpose of this review is to provide a better understanding regarding the involvement of risk factors in the molecular mechanisms associated with PD pathogenesis, as well as to provide insight into disease prevention and novel therapeutic interventions.

Understanding human aging and the fundamental cell signaling link in age-related diseases: the middle-aging hypovascularity hypoxia hypothesis

Aging-related hypoxia, oxidative stress, and inflammation pathophysiology are closely associated with human age-related carcinogenesis and chronic diseases. However, the connection between hypoxia and hormonal cell signaling pathways is unclear, but such human age-related comorbid diseases do coincide with the middle-aging period of declining sex hormonal signaling. This scoping review evaluates the relevant interdisciplinary evidence to assess the systems biology of function, regulation, and homeostasis in order to discern and decipher the etiology of the connection between hypoxia and hormonal signaling in human age-related comorbid diseases. The hypothesis charts the accumulating evidence to support the development of a hypoxic milieu and oxidative stress-inflammation pathophysiology in middle-aged individuals, as well as the induction of amyloidosis, autophagy, and epithelial-to-mesenchymal transition in aging-related degeneration. Taken together, this new approach and strategy can provide the clarity of concepts and patterns to determine the causes of declining vascularity hemodynamics (blood flow) and physiological oxygenation perfusion (oxygen bioavailability) in relation to oxygen homeostasis and vascularity that cause hypoxia (hypovascularity hypoxia). The middle-aging hypovascularity hypoxia hypothesis could provide the mechanistic interface connecting the endocrine, nitric oxide, and oxygen homeostasis signaling that is closely linked to the progressive conditions of degenerative hypertrophy, atrophy, fibrosis, and neoplasm. An in-depth understanding of these intrinsic biological processes of the developing middle-aged hypoxia could provide potential new strategies for time-dependent therapies in maintaining healthspan for healthy lifestyle aging, medical cost savings, and health system sustainability.

Efficacy of collagenase Clostridium histolyticum in men with congenital penile curvature

BACKGROUND

Collagenase Clostridium histolyticum (CCH) has been proven effective in multiple subpopulations of PD men; however, no studies have evaluated its role with congenital penile curvature (CPC).

AIM

To evaluate the safety and efficacy of CCH in men with CPC.

METHODS

A prospective registry was queried of men undergoing CCH injections at our institution. Beginning in 2016, CCH was administered to CPC men using a similar protocol to PD. A comparative analysis was performed between cohorts to evaluate the safety and efficacy of therapy.

OUTCOMES

Objective measures included penile length and curvature, while subjective outcomes included standardized (International Index of Erectile Function and Peyronie's Disease Questionnaire) and non-standardized assessments. Curvature outcomes were categorized as follows: 1 - included all men, with the most recent assessment considered final, and 2 - only men who had completed eight CCH injections or stopped early due to satisfaction.

RESULTS

From 2014 to Oct 2021, a total of 453 men (408 PD, 45 CPC) underwent one or more CCH injections. In comparing cohorts, CPC men were younger (33 vs 58 years, p<0.0001), had lesser baseline curvatures (52.5 vs 65°, p<0.01), more ventral curves (25.7 vs 9.2%, p<0.01), and longer penile lengths (12.5 vs 12.0 cm, p=0.04). Following treatment, both cohorts experienced similar curvature improvements. Specifically, PD men experienced 20-25° or 33-35% improvements depending on definition compared to 25-30° or 40-50% in CPC men (all p-values >0.05). CPC and PD men also demonstrated similar changes on standardized questionnaires, with the exception of the Psychological and Physical subdomain, which was more improved in CPC men (-11 vs -4, p<0.01). Baseline curvature was positively correlated with greater absolute (degree) and relative (percent) improvements. Adverse events were similar between groups after controlling for confounders.

CLINICAL IMPLICATIONS

CCH may be safely and effectively administered in men with CPC. These data provide the first evidence for the efficacy of a non-surgical therapeutic option in this cohort.

STRENGTHS AND LIMITATIONS

Strengths - large, prospective series with standardized assessments; Limitations - non-randomized study, short-term follow-up, and lack of standardized method to differentiate CPC from PD.

CONCLUSIONS

CCH may be safely and effectively administered to men with CPC, with similar success rates compared to PD. Increasing curvature was associated with greater absolute (degree) and relative (percent) improvements, supporting the role for CCH in men with mild, moderate, or severe curvatures. External validation is warranted prior to routine implementation.

Peyronie's Disease: An Outcomes-Based Guide to Non-Surgical and Novel Treatment Modalities

The clinical landscape of Peyronie's disease is everchanging. There has been growing interest in non-invasive therapeutic options that could assist patients with achieving a meaningful reduction in penile curvature without surgical intervention. These therapies are wide-ranging in terms of their mechanisms of action, efficacies, and short- and long-term safety profiles. Recently, an abundance of outcomes literature on longstanding and novel non-surgical treatment modalities has been published. For sexual medicine providers hoping to offer patients the most up-to-date and evidence-based treatments for the management of Peyronie's disease, it can be challenging to gain a thorough understanding of this body of literature. In this clinical management review, the workup and current theories on the pathophysiology of Peyronie's disease are reviewed, and the most recent outcomes data on the currently available non-surgical treatment modalities are presented. With an accurate understanding of the current landscape of Peyronie's disease treatment, sexual health providers will be able to better evaluate and engage in evidence-based shared decision-making with their patients.

Improvement in the ability to have sex in patients with Peyronie's disease treated with Collagenase Clostridium histolyticum

Objective

To describe the results of intralesional Collagenase Clostridium histolyticum (CCH) treatment in patients with Peyronie's disease (PD) in real-world setting. PD is characterized by curvature of the erect penis caused by fibrotic tissue in the tunica albuginea.

Patients and methods

Patients with stable PD and curvature of 30° to 90° were prospectively enrolled. CCH injections were initially given using a scheme of four cycles of two injections within 48-72 h every 6 weeks. Later using a modified scheme of three injections every 4 weeks, combined with a vacuum erection device (VED) twice daily. All patients were requested to take pictures of the erect penis prior to and following treatment, from above and laterally. Curvature was measured by three independent researchers based on the provided pictures using a goniometer. Furthermore, patients filled in the Peyronie Disease Questionnaire-NL (PDQ-NL) and Patient Reported Outcome Measurement (PROM).

The primary outcome was reduction in curvature and the ability to have penetrating sex again. Secondary outcomes include pain scores during injections, changes in PDQ-NL, PROM and complications of CCH treatment.

Results

Sixty-three patients were included, mean age was 56.0 years (range 39-70) and mean reduction in curvature 20.6° (SD 10.2, range 5-49); 74.5% of the patients were able to have penetrating sex again following treatment, compared with 41.2% prior to treatment. According to the PROM questions, sexual improvement was seen in 66.7% of patients. The satisfaction rate was 6.8 (SD 1.8). All patients save two recommend treatment.

Conclusions

Intralesional treatment with CCH in men with PD leads to a mean curvature improvement of 20.6°. Following treatment, 74.5% of men were able to have sexual intercourse and 54.9% of the couples were satisfied with their sex life. No major complications occurred in the patients treated with CCH. CCH is not available in Europe anymore despite good results.

The Function of BDNF and Its Receptor in the Male Genitourinary System and Its Potential Clinical Application

Background: Brain-derived neurotrophic factor (BDNF), as a member of the nerve growth factor family, has been mentioned more and more frequently in recent literature reports. Among them, content about the male genitourinary system is also increasing. Objective and Rationale: BDNF plays an important role in the male genitourinary system. At the same time, the literature in this field is constantly increasing. Therefore, we systematically summarized the literature in order to more intuitively show the function of BDNF and its receptor in the male genitourinary system and its potential clinical application. Search Methods: An electronic search of, e.g., PubMed, scholar.google and Scopus, for articles relating to BDNF and its receptor in the male genitourinary system. Outcomes: In the male genitourinary system, BDNF and its receptors TrkB and p75 participate in a series of normal physiological activities, such as the maturation and morphogenesis of testes and epididymis and maintenance of isolated sperm motility. Similarly, an imbalance of the circulating concentration of BDNF also mediates the pathophysiological process of many diseases, such as prostate cancer, benign prostatic hyperplasia, male infertility, diabetes erectile dysfunction, penile sclerosis, and bladder fibrosis. As a consequence, we conclude that BDNF and its receptor are key regulatory proteins in the male genitourinary system, which can be used as potential therapeutic targets and markers for disease diagnosis.

RANTES Concentration at the Time of Surgery Is Associated With Postoperative Stiffness in Patients Undergoing ACL Reconstruction

BACKGROUND

Patients undergoing anterior cruciate ligament (ACL) reconstruction have been shown to be at risk for postoperative arthrofibrosis. Diagnostic biomarkers associated with the development of postoperative stiffness are unknown.

HYPOTHESIS

Biomarkers found in the synovial fluid at the time of surgery are associated with the development of postoperative arthrofibrosis in a cohort of patients undergoing ACL reconstruction.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Patients undergoing ACL reconstruction were prospectively enrolled. Synovial fluid was collected before surgical incision. A cohort of patients with postoperative stiffness requiring manipulation under anesthesia (MUA) and/or lysis of adhesions (LOA) was retrospectively identified. Matching of cases to controls was performed using a 1:2 pair matching algorithm. Risk factor-adjusted single-biomarker and multivariable models were used to assess the association of synovial fluid biomarkers with postoperative stiffness requiring MUA/LOA. Stepwise logistic regression controlling for clinical risk factors was used to identify biomarkers that are possible predictors of postoperative stiffness.

RESULTS

A total of 11 cases (3 male, 8 female) were identified and matched with 21 controls (6 male, 15 female) with no significant differences in age, sex, smoking history, or days from injury to surgery. Concentrations of the biomarker regulated upon activation, normal T-cell expressed and presumably secreted (RANTES) were significantly higher in patients requiring MUA/LOA versus controls (694.20 pg/mL [interquartile range, 214.75-3428.79] vs 113.04 pg/mL [interquartile range, 32.81-517.91], respectively; P = .034). On single-biomarker models, RANTES (odds ratio, 2.28; 95% CI, 1.29-5.37; P = .019) and basic fibroblast growth factor (bFGF) (odds ratio, 1.91; 95% CI, 1.07-3.99; P = .047) were associated with increased risk of postoperative stiffness requiring MUA/LOA after ACL reconstruction. Stepwise logistic regression identified 3 biomarkers that are possible predictors of postoperative stiffness, which were included in the final model: Interleukin 1 receptor antagonist (IL-1RA) (P = .198), bFGF (P = .157), and RANTES (P = .046).

CONCLUSION

Higher concentrations of synovial fluid biomarkers bFGF and RANTES were associated with increased risk for stiffness requiring intervention after ACL reconstruction. Interleukin 6 (IL-6), vascular endothelial growth factor A (VEGF-A), tissue inhibitor of metalloproteinases 1 (TIMP-1), interleukin 1 receptor antagonist (IL-1RA), matrix metalloproteinase 3 (MMP-3), monocyte chemotactic protein 1 (MCP-1), and macrophage inflammatory protein 1B (MIP-1B) were not associated with the development of postoperative arthrofibrosis.

A Consistent Lack of Consistency in Defining the Acute and Chronic Phases of Peyronie's Disease: A Review of the Contemporary Literature

INTRODUCTION

Treatment recommendations for Peyronie's Disease (PD) differ based on whether a patient is in the acute/active versus chronic/stable phase of the disease, yet there are no agreed upon criteria for defining these clinical entities.

OBJECTIVES

To review the criteria used to define acute and chronic phase PD in modern PD intervention studies.

METHODS

We performed a search engine review to identify indexed publications for PD intervention studies and review articles / meta-analyses from the year 2011-2020. Outcomes results were catalogued and summarized across articles. As a result of the substantial heterogeneity of outcome measures and follow-up intervals, meta-analytic techniques were not applied to the data analysis.

RESULTS

We identified a total of 104 studies that met inclusion criteria and had available information for review (n = 79 primary intervention studies; n = 25 review articles/meta-analyses/guidelines). Among the queried studies, we were unable to identify a consensus with respect to the criteria used to define acute and chronic phases of PD. 33% of primary intervention studies did not specifically define their criteria for acute and chronic phase PD, despite referencing these populations as part of the inclusion criteria in many instances. Studies used heterogenous criteria including total symptom duration, duration of "stable" symptoms, and presence/absence of pain.

CONCLUSION

Due to varying definitions across the literature, we were unable to create a standardized definition of acute and chronic phase Peyronie's in terms of time. Our findings emphasize the need for greater consensus in defining the treatment cohorts with future studies that assess treatment for men with PD.

Are neutrophil–lymphocyte and platelet–lymphocyte ratios useful for determining active phase of Peyronie’s disease?

Background:

Management options for Peyronie’s disease (PD) are determined by the phase of the condition. Experts counsel against surgical intervention during the active phase of PD. Patients with chronic phase of PD are offered either collagenase injections or surgical intervention. Accurately characterising a patient’s phase of PD is crucial in determining the appropriate treatment option.

Objective:

To investigate neutrophil–lymphocyte ratio (NLR) and platelet–lymphocyte ratio (PLR) as possible predictors for the determination of acute or chronic phase of PD.

Methods:

This study retrospectively queried all patients who presented for initial diagnosis of PD from 2016 to 2020 and had complete blood count (CBC) laboratory values before initial therapy. PD phase was defined per the American Urological Association guidelines. The active phase of PD was defined as a changing penile curvature and/or growing palpable plaque. The chronic phase of PD was defined as a stabilised penile curvature. All statistical analyses were two-tailed, using a significance level of 0.05.

Results:

One hundred nine patients met inclusion: 27 (25%) active phase and 82 (75%) chronic phase patients. Demographic and erectile characteristics were not statistically different between the two groups. NLR and PLR values between active and chronic phase patients were comparable ( p > 0.05). A linear regression evaluated correlations between the duration of PD and either NLR or PLR. Neither NLR nor PLR was correlated with PD duration on Spearman, Pearson, or Kandall tests. In addition, NLR and PLR were not noted to be predictors of PD phase on multiple logistic regression. Finally, a receiver operator characteristic curve was generated. NLR and PLR yielded an area under curve of 58% and 57.8%, respectively.

Conclusions:

Two recent studies suggested NLR and PLR could be used to predict the phases of PD. However, after evaluating a cohort of 109 men from our institution, our data do not support the use of peripheral blood PLR or NLR to determine the phase of PD.

The contribution of the immune system to genitourinary fibrosis

Fibrotic diseases of the genitourinary tract are devastating and incompletely understood pathologies. These diseases include urethral and ureteral strictures, retroperitoneal fibrosis, and Peyronie's disease. They can contribute to obstructive uropathy and sexual dysfunction. Poor understanding of the pathophysiology of these diseases severely limits our ability to prevent and treat them. Genitourinary fibrotic diseases likely represent related pathologies that share common underlying mechanisms involving wound healing in response to injury. These diseases share the common feature of extracellular matrix abnormalities-such as collagen deposition, transforming growth factor-β accumulation, and dysregulation of collagen maturation-leading to abnormal tissue stiffness. Given the association of many of these diseases with autoimmunity, a systemic pro-inflammatory state likely contributes to their associated fibrogenesis. Herein, we explore the immunologic contribution to fibrogenesis in several fibrotic diseases of the genitourinary system. Better understanding how the immune system contributes to fibrosis in these diseases may improve prevention and therapeutic strategies and elucidate the functions of immunologic contributors to fibrosis in general.

Pathological Significance of Macrophages in Erectile Dysfunction Including Peyronie's Disease

Erectile function is regulated by complex mechanisms centered on vascular- and nerve-related systems. Hence, dysregulation of these systems leads to erectile dysfunction (ED), which causes mental distress and decreases the quality of life of patients and their partners. At the molecular level, many factors, such as fibrosis, lipid metabolism abnormalities, the immune system, and stem cells, play crucial roles in the etiology and development of ED. Although phosphodiesterase type 5 (PDE5) inhibitors are currently the standard treatment agents for patients with ED, they are effective only in a subgroup of patients. Therefore, further insight into the pathological mechanism underlying ED is needed to discuss ED treatment strategies. In this review, we focused on the biological and pathological significance of macrophages in ED because the interaction of macrophages with ED-related mechanisms have not been well explored, despite their important roles in vasculogenic and neurogenic diseases. Furthermore, we examined the pathological significance of macrophages in Peyronie’s disease (PD), a cause of ED characterized by penile deformation (visible curvature) during erection and pain. Although microinjury and the subsequent abnormal healing process of the tunica albuginea are known to be important processes in this disease, the detailed etiology and pathophysiology of PD are not fully understood. This is the first review on the pathological role of macrophages in PD.

Peyronie Disease as a Marker of Inflammation-Is There Hope on the Horizon?

Although the description of Peyronie disease, a connective tissue disorder involving the growth of fibrous plaques in the soft tissue of the penis, is attributed to François de la Peyronie, surgeon to Louis XV of France, there are reports previous to that time. Over the intervening 450 years, a variety of empiric treatments, varying in barbarity, have been proposed. The frequency of this condition and the etiology of the fibrosis are unknown. Quality of life for affected men and their partners is adversely impacted. In this review, the authors summarize the history of the discovery of this condition, review contemporary management approaches, and address the pathophysiology leading to the underlying disordered fibrosis. The potential immunomodulatory role of testosterone as well as inflammatory conditions and environmental stimuli that may provoke fibrosis are also considered. Peyronie disease may be part of a spectrum of fibrotic conditions, including Dupuytren contracture. Treatment strategies to date have focused on reversing fibrosis; work is needed to prevent fibrosis and to accurately document disease prevalence.

[Efficacy and safety of local injections treatments for Peyronie's disease: Review of the literature]

AIM

To assess the efficacy and safety of local injection used to reduce penile curvature in Peyronie's disease.

METHODS

A review of the literature was carried out according to the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyzes) on the Medline database in April 2020, with the research: "collagenase"[All Fields] OR "Interferon"[All Fields] OR "verapamil"[All Fields] OR "betamethasone"[All Fields] OR "hyaluronic acid"[All Fields] OR "Platelet-Rich Plasma"[All Fields] OR "Stem Cells"[All Fields] AND "peyronie's"[All Fields] AND Controlled Clinical Trial[ptyp]. Only controlled studies with placebo group were included in this review.

RESULTS

Of the 35 articles identified, 6 placebo-controlled studies were finally included. Intra-plaque injections of verapamil did not show improvement in penile curvature. Injections of interferon α 2b and clostridium histolyticum collagenase allowed a statistically significant improvement in terms of curvature reduction: 13.5 versus 4.5 degrees P<0.01) and 17 versus 9.3 degrees P<0.0001 respectively. However, interferon α 2b is not available in France for Peyronie's disease and clostridium histolyticum collagenase is no longer authorized since March 1, 2020. No controlled studies are available on corticosteroids, hyaluronic acid, platelet-rich plasma or stem cells injections.

CONCLUSION

To correct the deformity in Peyronie's disease in the chronic phase, there is no effective solution currently available in France based on controlled studies. Surgery retains its place for the correction of a curvature of at least 30° associated with a sexual handicap in the stable phase, however at the cost of potential adverse effects. Stem cell or Platelet-Rich Plasma injection might be an injectable therapeutic alternative but need controlled studies.

Mechanical characterization of fibrotic and mineralized tissue in Peyronie's disease

Peyronie's disease affects penile mechanics, but published research lacks biomechanical characterization of affected tunica albuginea. This work aims to establish mechanical testing methodology and characterize pathological tissue mechanics of Peyronie's disease. Tunica albuginea was obtained from patients (n = 5) undergoing reconstructive surgery for Peyronie's disease, sectioned into test specimens (n = 12), stored frozen at -20 °C, and imaged with micro-computed tomography (µCT). A tensile testing protocol was developed based on similar soft tissues. Correlation of mechanical summary variables (force, displacement, stiffness, work, Young's modulus, ultimate tensile stress, strain at ultimate tensile stress, and toughness) and µCT features were assessed with linear regression. Specimens empirically grouped into hard or soft stress-strain behavior were compared using a Student's t-test. Surface strain and failure patterns were described qualitatively. Specimens displayed high inter- and intra-subject variability. Mineralization volume was not correlated with mechanical parameters. Empirically hard tissue had higher ultimate tensile stress. Failure mechanisms and strain patterns differed between mineralized and non-mineralized specimens. Size, shape, and quantity of mineralization may be more important in determining Peyronie's disease plaque behavior than presence of mineralization alone, and single summary variables like modulus may not fully describe mechanical behavior.

UVA-Degradable Collagenase Nanocapsules as a Potential Treatment for Fibrotic Diseases

Peyronie and Dupuytren are pathologies characterized by the appearance of localized fibrotic lesions in an organ. These disorders originate from an excessive production of collagen in the tissue provoking dysfunction and functional limitations to the patients. Local administration of collagenase is the most used treatment for these fibrotic-type diseases, but a high lability of the enzyme limits its therapeutic efficacy. Herein, we present a novel methodology for the preparation of collagenase nanocapsules without affecting its enzymatic activity and capable of releasing the enzyme in response to an ultraviolet A (UVA) light stimulus. Polymeric coating around collagenase was formed by free-radical polymerization of acrylamide-type monomers. Their degradation capacity under UVA irradiation was provided by incorporating a novel photocleavable acrylamide-type crosslinker within the polymeric framework. This property allowed collagenase release to be triggered in a controlled manner by employing an easily focused stimulus. Additionally, UVA irradiation presents considerable benefits by itself due to its capacity to induce collagenase production in situ. An expected synergistic effect of collagenase nanocapsules in conjunction with UVA effect may present a promising treatment for these fibrotic diseases.

Patients with Dupuytren's Contracture, Ledderhose Disease, and Peyronie's Disease are at higher risk of arthrofibrosis following total knee arthroplasty

BACKGROUND

Total knee arthroplasty (TKA) is a successful treatment for patients with late stage osteoarthritis, yet arthrofibrosis remains a consistent cause of TKA failure. Dupuytren's, Ledderhose and Peyronie's Diseases are related conditions of increased fibroblast proliferation. The aim of this study was to identify whether an association exists between these conditions and arthrofibrosis following TKA.

METHODS

Patient records were queried from 2010 to 2016 using an administrative claims database to compare the rates of arthrofibrosis, manipulation under anesthesia (MUA), lysis of adhesions (LOA), and revision TKA in patients with independent chart diagnoses of Dupuytren's Contracture, Ledderhose, or Peyronie's Diseases versus those without. Complications were queried and compared using multivariate logistic regression.

RESULTS

Patients with Dupuytren's (n = 5,232) and Ledderhose (n = 50,716) had a significantly higher rate of ankylosis following TKA: 30-days (OR, 1.54; OR, 1.23), 90-days (OR, 1.20; OR, 1.24), 6-months (OR, 1.23; OR, 1.23), and 1-year (OR, 1.28; OR, 1.23), while patients with Peyronie's (n = 1,186) had a higher rate of diagnosis at 6-months (OR, 1.37) and 1-year (OR, 1.35). Patients with diagnoses of any of the fibroproliferative diseases had a statistically higher risk of MUA at 90-days, 6-month, and 1-year following primary TKA. These cohorts did not have a significantly higher rate of revision TKA.

CONCLUSION

There is an increased odds risk of arthrofibrosis and MUA in patients who have undergone TKA and have a diagnosis of Dupuytren's Contracture, Ledderhose, or Peyronie's Diseases. Improvements to frequency and application of post-operative treatment should be considered in these cohorts to improve outcomes.

Efficacy of Collagenase Clostridium histolyticum (Xiapex®) in Patients with the Acute Phase of Peyronie's Disease

BACKGROUND AND OBJECTIVE: Plaque formation ordinarily takes place in the acute phase of Peyronie's disease. There is no unanimous consent regarding the management of the acute phase of Peyronie's disease. The objective of this study was to evaluate the advantages of using a single intralesional injection of collagenase Clostridium histolyticum in patients with the active phase of Peyronie's disease and to assess its effect on disease progression by reducing penile curvature and ameliorating pain during sexual intercourse.

METHODS

Sexually active men aged older than 18 years with the acute phase of Peyronie's disease were enrolled. All patients received treatment with a single intralesional injection of collagenase Clostridium histolyticum. The primary outcome of the study was the change in penile curvature after treatment while secondary outcomes were the change in sexual function (International Index of Erectile Function [IIEF-5]) and in the Peyronie Disease Questionnaire (PDQ) and its sub-scores, PDQ-PS (psychological symptoms), PDQ-PP (penile pain) and PDQ-BD (bother disease).

RESULTS

Overall, 74 patients were enrolled. Mean penile curvature at baseline was 41.1° ± 12.2°. The mean changes before and at the 3-month evaluation in terms of penile curvature, Visual Analog Scale score at rest, and Visual Analog Scale score during intercourse were - 19.3 ± 8.4 (p < 0.0001), - 0.8 ± 1.1 (p < 0.0001) and - 3.8 ± 0.9 (p < 0.0001) with the benefit persisting also after 6 months. Moreover, improvements of mean IIEF-5 score (1.1 ± 0.9, p = 0.03; 0.9 ± 0.5, p = 0.02), PDQ-PS (- 2.7 ± 2.2; - 2.5 ± 2.0, p = 0.01), PDQ-PP (- 1.2 ± 1.6; - 1.1 ± 1.2, p = 0.02) and PDQ-BD (- 3.8 ± 3.4; - 3.5 ± 3.1, p = 0.001) were observed 3 and 6 months after the end of treatment, respectively. At the multivariable regression analysis, the time since disease onset (modelled with non-linear terms) and baseline curvature were independently associated with the degree of curvature improvement (coefficient: 0.30; 95% confidence interval 0.16-0.44) after a single intralesional injection (all p < 0.03).

CONCLUSIONS

Although intralesional therapy with collagenase Clostridium histolyticum is not yet indicated for the acute phase of Peyronie's disease, these preliminary results suggest the effectiveness of this minimally invasive option by improving penile curvature and IIEF-5 and PDQ scores.

New insights into the pathogenesis of Peyronie's disease: A narrative review

Peyronie's disease (PD) is a benign, progressive fibrotic disorder characterized by scar or plaques within the tunica albuginea (TA) of the penis. This study provides new insights into the pathogenesis of PD based on data from different studies regarding the roles of cytokines, cell signaling pathways, biochemical mechanisms, genetic factors responsible for fibrogenesis. A growing body of literature has shown that PD is a chronically impaired, localized, wound healing process within the TA and the Smith space. It is caused by the influence of different pathological stimuli, most often the effects of mechanical stress during sexual intercourse in genetically sensitive individuals with unusual anatomical TA features, imbalanced matrix metalloproteinase/tissue inhibitor of metalloproteinase (MMP/TIMP), and suppressed antioxidant systems during chronic inflammation. Other intracellular signal cascades are activated during fibrosis along with low expression levels of their negative regulators and transforming growth factor-β1 signaling. The development of multikinase agents with minimal side effects that can block several signal cell pathways would significantly improve fibrosis in PD tissues by acting on common downstream mediators.

Intralesional Injection Therapy and Atypical Peyronie's Disease: A Systematic Review

INTRODUCTION

Peyronie's disease (PD) is an inflammatory disorder of the tunica albuginea causing fibrotic changes including abnormal penile curvature, pain, and erectile dysfunction. Approximately 10% of PD patients will have atypical features including ventral plaques, hourglass deformities, unilateral indentations, severely shortened penile length, and multiplanar curvatures. Currently, the only intralesional treatment approved by the United States Food and Drug Administration is considered off-label for atypical PD. Furthermore, treatment of atypical PD, especially ventral plaques, is met with hesitation, in part due to potential urethral injury.

OBJECTIVES

To systematically review the available literature for the safety and efficacy of intralesional injections for atypical PD.

METHODS

A thorough literature search of the PubMed database was performed on manuscripts published between 1982 and 2020. Keywords included atypical Peyronie's disease, ventral plaque, hourglass deformity, and injection.

RESULTS

15 articles met the criteria for evaluation. Overall, 1,357 patients with PD were treated with intralesional therapy, of which 250 patients were considered to have an atypical presentation. 162 (648%) of the patients were treated with intralesional collagenase Clostridium histolyticum, 49 (19.6%) with verapamil, 29 (11.6%) with interferon alfa-2b, 5 (2.0%) with hyaluronic acid, and another 5 (2.0%) with onabotulinumtoxinA. There was only 1 reported severe adverse event (penile fracture), which was surgically repaired. There were no reports of urethral injury.

CONCLUSION

Intralesional injection treatment may be a safe alternative option for atypical PD. There is a great need for future research to closely monitor the role of intralesional therapy in this cohort. Choi EJ, Xu P, El-Khatib FM, et al. Intralesional Injection Therapy and Atypical Peyronie's Disease: A Systematic Review. Sex Med Rev 2021;9:434-444.