Caveolin-1 scaffolding domain-derived peptide enhances erectile function by regulating oxidative stress, mitochondrial dysfunction, and apoptosis of corpus cavernosum smooth muscle cells in rats with cavernous nerve injury.

AIM: Increased corpus cavernosum smooth muscle cells (CCSMCs) apoptosis in the penis due to cavernous nerve injury (CNI) is a crucial contributor to erectile dysfunction (ED). Caveolin-1 scaffolding domain (CSD)-derived peptide has been found to exert potential antiapoptotic properties. However, whether CSD peptide can alleviate CCSMCs apoptosis and ED in CNI rats remains unknown. The study aimed to determine whether CSD peptide can improve bilateral CNI-induced ED (BCNI-ED) by enhancing the antiapoptotic processes of CCSMCs. MAIN METHODS: Fifteen 10-week-old male Sprague-Dawley (SD) rats were randomly classified into three groups: sham surgery (Sham) group and BCNI groups that underwent saline or CSD peptide treatment respectively. At 3 weeks postoperatively, erectile function was assessed and the penis tissue was histologically examined. Furthermore, an in vitro model of CCSMCs apoptosis was established using transforming growth factor-beta 1 (TGF-ß1) to investigate the mechanism of CSD peptide in treating BCNI-ED. KEY FINDINGS: In BCNI rats, CSD peptide significantly prevented ED and decreased oxidative stress, the Bax/Bcl-2 ratio, and the levels of caspase3. TGF-ß1-treated CCSMCs exhibited severe oxidative stress, mitochondrial dysfunction, and apoptosis. However, CSD peptide partially reversed these alterations. SIGNIFICANCE: Exogenous CSD peptide could improve BCNI-ED by inhibiting oxidative stress, the Bax/Bcl-2 ratio, and caspase3 expression in penile tissue. The underlying mechanism might involve the regulatory effects of CSD peptide on oxidative stress, mitochondrial dysfunction, and apoptosis of CCSMCs following CNI. This study highlights CSD peptide as an effective therapy for post-radical prostatectomy ED (pRP-ED).

Penile-scrotal erythrodysesthesia among rectal cancer patients receiving fluoropyrimidine-based chemoradiation: a case report series.

BACKGROUND: Palmar-plantar erythrodysesthesia (PPE) is a slowly developing cutaneous reaction commonly experienced by patients treated with fluoropyrimidines. While erythrodysesthesia normally presents in a palmar-plantar distribution, it can also present with genital involvement, but this presentation is likely underreported and incorrectly attributed to an acute reaction from radiation therapy. This article aims to define erythrodysesthesia of the penis and scrotum as a rare but significant side effect of capecitabine. CASE PRESENTATION: We identified five cases of moderate to severe penis and scrotal erythrodysesthesia over a 2-year period at a large tertiary cancer center, representing an estimated incidence of 3.6% among male patients with rectal cancer who were treated with fluoropyrimidine-based chemoradiation within our institution. CONCLUSIONS: Improved understanding of erythrodysesthesia involving the penis and scrotum can facilitate early identification and treatment of symptoms, and possibly prevent the discontinuation or delay of cancer treatment in patients treated with capecitabine and similar drugs. These clinical advances would improve and prolong patient quality of life during cancer treatment and prevent complications that result in hospitalization.

Effects of ketamine on penile tissues in an experimental priapism model in rats.

BACKGROUND: This study aimed to evaluate the histopathological and biochemical effects of ketamine on penile tissues following ischemia-reperfusion injury induced by priapism. METHODS: Twenty-four male rats were randomized into three groups. Group 1 served as the control group. Group 2 underwent the priapism model to induce ischemia-reperfusion injury. Group 3, the treatment group, experienced a similar ischemia-reperfusion model as Group 2; additionally, 50 mg/kg of ketamine was administered intraperitoneally just before reperfusion. Blood biochemical analyses and penile histopathological evaluations were performed. RESULTS: In Group 3, significant improvements were observed in all histopathological scores, including desquamation, edema, inflammation, and vasocongestion compared to Group 2 (p<0.001). Blood biochemical analyses showed that the malondialdehyde (MDA) levels were recorded as 10 in Group 2, with a significant decrease in Group 3 (p=0.013). Similarly, proinflammatory cytokine levels, including interleukin-1 beta (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α), were found to be suppressed in Group 3 compared to Group 2 (p=0.003, p=0.022, and p=0.028, respectively). Antioxidant enzyme activities, such as glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD), were higher in Group 3 compared to Group 2 (p=0.016 and p=0.024, respec-tively). CONCLUSION: Ketamine is an effective anesthetic agent in alleviating the effects of penile ischemia-reperfusion injury.

"Bone in the penis" or fasciitis ossificans of the penis - a first time description of a pseudo-tumor at an extraordinary site.

BACKGROUND: Fasciitis ossificans is a rare subtype of nodular fasciitis, a benign soft tissue tumor with reactive characteristics. Due to its rapid growth, it is often misdiagnosed as a malignant tumor. While fasciitis ossificans commonly originates from the subcutaneous tissue and can appear throughout the body, it may also arise from extraordinary sites. CASE PRESENTATION: We report the first-ever documented case of fasciitis ossificans arising from the penis in a male patient who presented with a tumor on the glans penis. The tumor was surgically resected due to suspicion of penile cancer. Initial histopathological analysis led to a misdiagnosis of squamous cell carcinoma. However, pathological consultation ultimately confirmed the diagnosis of fasciitis ossificans of the penis originating from the glans penis by demonstrating ossification. CONCLUSION: This case underscores the importance of considering fasciitis ossificans in the differential diagnosis of soft tissue tumors, even in unusual locations such as penile soft tissue.

MicroRNA-503-5p protects streptozotocin-induced erectile dysfunction in diabetic rats by downregulating SYDE2.

Plentiful studies have clarified miRNAs take on a key role in the sexual dysfunction of diabetic rats. This study aimed to figure out microRNA (miR)-503-5p/SYDE2 axis' latent mechanisms in streptozotocin-induced diabetic rat sexual dysfunction. A model of erectile dysfunction (ED) in diabetic rats was established by injecting streptozotocin. MiR-503-5p and SYDE2 in ED rats were altered by injection of miR-503-5p mimic or si/oe-SYDE2. The targeting link between miR-503-5p and SYDE2 was testified. ICP/MAP value was tested by pressure sensor; Penile capillary abundance was assessed; Penile cGMP and AGEs were detected; penile smooth muscle cell apoptosis was assessed; MiR-503-5p and SYDE2 were tested. In streptozotocin-induced ED rats, miR-503-5p was reduced and SYDE2 was elevated. Elevating miR-503-5p or silencing of SYDE2 can enhance penile erection rate, ICP/MAP value, capillary abundance, and cGMP but reduce AGEs and penile smooth muscle cell apoptosis rate in ED rats. Strengthening SYDE2 with elevating miR-503-5p turned around the accelerating effect of elevated miR-503-5p on penile erection in ED rats. SYDE2 was a downstream target gene of miR-503-5p. MiR-503-5p protects streptozotocin-induced sexual dysfunction in diabetic rats by targeting SYDE2.

Renal Cell Carcinoma Metastasis to the Penis: A Case Report and Literature Review.

Metastasis to the penis from renal cell carcinoma (RCC) or any other primary cancer site is unusual; when it does occur, it often involves multiple organs. A 75-year-old man presented with penile pain and swelling. Three months earlier, he had open radical nephrectomy with thrombectomy and was diagnosed with clear-cell RCC with tumor thrombosis in the inferior vena cava. The follow-up imaging indicated metastasis to the penis, prompting a total penectomy due to worsening pain. The excised mass displayed features consistent with metastatic RCC. This case underscores the need to consider rare metastatic sites, such as the metastasis of RCC to the penis, in RCC patients.

Poly-L-lactic acid/gelatin electrospun membrane-loaded bone marrow-derived mesenchymal stem cells attenuate erectile dysfunction caused by cavernous nerve injury.

Radical prostatectomy (RP) can cause neurogenic erectile dysfunction (ED), which negatively affects the quality of life of patients with prostate cancer. Currently, there is a dearth of effective therapeutic strategies. Although stem cell therapy is promising, direct cell transplantation to injured cavernous nerves is constrained by poor cell colonization. In this study, poly-L-lactic acid (PLLA)/gelatin electrospun membranes (PGEM) were fabricated to load bone marrow-derived mesenchymal stem cells (BM-MSCs) as a patch to be placed on injured nerves to alleviate ED. This study aimed to establish a promising and innovative approach to mitigate neurogenic ED post-RP and lay the foundation for modifying surgical procedures. Electrospinning and molecular biotechnology were performed in vitro and in vivo, respectively. It was observed that PGEM enhanced the performance of BM-MSCs and Schwann cells due to their excellent mechanical properties and biocompatibility. The transplanted PGEM and loaded BM-MSCs synergistically improved bilateral cavernous nerve injury-related ED and the corresponding histopathological changes. Nevertheless, transplantation of BM-MSCs alone has been verified to be ineffective. Overall, PGEM can serve as an ideal carrier to supply a more suitable survival environment for BM-MSCs and Schwann cells, thereby promoting the recovery of injured cavernous nerves and erectile function.

Surgical management of urethral obstruction secondary to perineal liposarcoma in a dog: a case report.

BACKGROUND: Swelling of the perineal region in male dogs is most commonly caused by a perineal hernia. Clinical signs associated with perineal hernia are constipation, tenesmus or stranguria. This case report documents a rare cause of perineal swelling created by the growth of a malignant tumour leading to urethral obstruction and subsequent stranguria. CASE PRESENTATION: An 11-year-old neutered male German Shepherd was presented for swelling in the perineal region and stranguria for three days. Complete blood count and serum biochemistry were unremarkable. Ultrasound revealed a heterogeneous mass in the perineal region. Retrograde urethrography showed a severe narrowing of the urethra caudal to the pelvis. A fine-needle aspirate of the mass was highly suspicious for liposarcoma. Staging was performed by computed tomography (CT) of the thorax and abdomen. Total penile amputation in combination with pubic-ischial pelvic osteotomy, transposition of the remaining urethra through the inguinal canal, V-Y-plasty cranial to the prepuce and preputial urethrostomy were performed to remove the tumour. Histopathology confirmed a well-differentiated liposarcoma with complete histological margins. Six months after the surgery the dog was doing well and there were no signs indicating local tumour recurrence. CONCLUSIONS: Wide surgical excision is generally recommended for soft tissue sarcomas, however this is sometimes not feasible for large tumours. In the case reported here, tumour resection was achieved by a combination of several surgical techniques with a good clinical outcome.

Soft tissue tumours of the penis. The 30-year Istituto Nazionale Tumori di Milano experience.

Objective: Small series and individual cases of penile soft tissue tumours are reported in the literature: these are rare tumours that represent less than 5% of all penile tumours. Methods: Penile soft tissue tumours were collected from the archive of the Department of Pathology at the Istituto Nazionale dei Tumori of Milan between January 1990 and October 2021. All available medical records were retrieved and reviewed to obtain clinical information. Results: Our series refers to the 30-year experience of highlighting the heterogeneity in the presentation and microscopic features of these rare sarcomas. 18 penile soft tissue tumours are described, 4 benign and 14 malignant. The mean age at diagnosis was 58.2 years (range 24-96 years) and 53.6 years among malignancies (range 24-89). The most frequent histotype was Kaposi's sarcoma (nr = 4) and very unusual histotypes were observed, namely low-grade fibromyxoid sarcoma, synovial sarcoma, proximal type epithelioid sarcoma and the first reported case of dedifferentiated liposarcoma of the penis. Conclusions: Among sarcomas of the genitourinary tract, tumours of the soft tissues of the penis are the rarest. Penile sarcomas can present at a young age. Kaposi's sarcoma in HIV-negative patients has a favorable outcome, while deep sarcomas have an aggressive behavior and poor prognosis.

Diagnostically Challenging Multifocal Penile Epithelioid Hemangioma Successfully Treated With Doxorubicin Hydrochloride.

ABSTRACT: Epithelioid hemangioma (EH), also known as angiolymphoid hyperplasia with eosinophilia, is an unusual vascular proliferation that tends to manifest in the head and neck region. Its occurrence on the penis is rare, with only scarce reported cases in the literature. The histopathological examination of this condition poses a challenge because it shares similarities with other entities, such as epithelioid hemangioendothelioma, epithelioid angiosarcoma, cutaneous epithelioid angiomatous nodule, or Kaposi sarcoma (KS). The infrequency of EH in penile locations underscores the need for accurate diagnostic differentiation and tailored treatment strategies for this atypical presentation. This case report highlights a rare instance of multifocal penile EH. The patient's lesions exhibited distinctive histopathologic features, with extensive eosinophilic infiltration, presence of necrosis, and infiltration to subcutaneous fat. The patient was treated with doxorubicin, a chemotherapy drug, with a very good response. This successful therapeutic outcome underscores the potential efficacy of doxorubicin in the management of multifocal penile EH. The comprehensive analysis of this case contributes to our understanding of the clinical presentation, histopathologic features, and treatment modalities for this rare penile tumor, providing valuable insights for future clinical considerations.

Primary preputial reconstruction following surgical excision of cutaneous mast cell tumours without penile amputation in eight dogs.

CASE HISTORY: Medical records from a single referral hospital (Davies Veterinary Specialists, Hitchin, UK) were reviewed to identify dogs (n = 8) with preputial cutaneous mast cell tumours (CMCT) that underwent surgical excision and primary preputial reconstruction, preserving the penis and urethra, after clients declined alternatives such as penile amputation and urethrostomy, from June 2017-June 2022. CLINICAL FINDINGS: Tumours had a median diameter of 21.5 (min 15, max 30) mm, were located cranioventrally (3/8), caudoventrally (1/8), laterally (2/8) and dorsally (2/8) relative to the prepuce and were diagnosed as CMCT based on cytology. No dogs had hepatic or splenic metastasis on cytology but inguinal lymph node metastasis was identified in 3/4 dogs sampled. TREATMENT AND OUTCOME: The owners of all dogs had declined penile amputation and scrotal urethrostomy. The CMCT were excised and primary reconstruction of the prepuce performed. Surgical lateral margins of 10, 20 or 30 mm were used and the deep margin excised the inner preputial lamina or underlying muscular fascia. The deep margin for caudoventral CMCT involved excision of the underlying SC adipose tissue. Preputial advancement was performed in 3/8 dogs to achieve adequate penile coverage. Histopathology confirmed all CMCT were Kiupel low grade, Patnaik grade II with complete margins in 6/8 dogs but identified metastasis only in one inguinal lymph node from one dog. Two dogs encountered minor complications (infection and a minor dehiscence) and one dog had a major complication (infection with major dehiscence). Median follow-up duration was 125 weeks, excluding one dog with 4 weeks of follow-up. None of the dogs experienced local recurrence or died of mast cell disease during the available follow-up period. CLINICAL RELEVANCE:  This clinical study evaluated a surgical alternative to penile amputation and advanced reconstructive techniques for Kuipel low/Patnaik grade II preputial CMCT when these procedures were declined by owners. Surgical excision of preputial CMCT with lateral margins of 10, 20 or 30 mm with primary preputial reconstruction is achievable with low morbidity and a good outcome when penile amputation and scrotal urethrostomy is not an option.

A pictorial review of scrotal and penile pathology on computed tomography.

Computed tomography (CT) may show a variety of scrotal and penile pathologic finding, but is usually not used as a first-line imaging due to its limited soft tissue contrast. Nonetheless, there are three main scenarios for imaging of the scrotum and penis with CT. Pathologies may be found incidentally in patients undergoing abdominal and pelvic CT scanning for different reasons. In emergency settings, CT is frequently performed, and the recognition of scrotal and penile pathologies by the reporting radiologist is crucial to ensure optimal patient treatment and outcome. If MRI scanning cannot be performed due to contraindications or is unavailable in resource, limited CT may be used for the further characterization of scrotal and penile pathology found on ultrasound. This pictorial review wants to familiarize general and emergency radiologists with the anatomy and possible pathological findings of the scrotum and penis on CT.

Peyronie's disease response to intralesional collagenase clostridium histolyticum therapy is independent of baseline testosterone.

BACKGROUND: Testosterone plays an important role in collagen metabolism, transforming growth factor-ß1 expression, and wound healing, which are all critical factors in pathogenesis of Peyronie's disease. Some clinical studies have suggested an association between Peyronie's disease and hypogonadism. OBJECTIVE: We sought to investigate whether baseline total testosterone levels influence response to intralesional collagenase clostridium histolyticum in Peyronie's disease. METHODS: A retrospective review of patients receiving collagenase clostridium histolyticum injections with available total testosterone levels within 1 year of initial injection was conducted at a single institution. Baseline demographics, hypogonadal status, total testosterone, number of collagenase clostridium histolyticum cycles, and pre- and post-treatment degrees of curvature were collected. Hypogonadism was defined as total testosterone <300 ng/dL. RESULTS AND DISCUSSION: Thirty-six men were included with mean age of 58.2 years (SD 10.4) and mean body mass index 26.8 (SD 3.2). The mean total testosterone was 459.2 ng/dL (SD 144.0), and four (11.1%) were hypogonadal. Mean pre-treatment curvature was 47.6°, and mean post-treatment curvature was 27.8°, with mean improvement of 19.9° (40.1%). Hypogonadal status was not significantly associated with more severe curvature, 46.4° among hypogonadal men as to 57.5° among eugonadal men (p = 0.32). On linear regression analysis, total testosterone did not significantly predict improvement in degrees (ß = -0.02; R2 = 0.06; p = 0.14) or percent (ß = 0.0; R2 = 0.05; p = 0.18). Improvement in neither degrees nor percent differed significantly by hypogonadal status (p = 0.41 and 0.82, respectively). The cycle number did significantly predict greater improvement in curvature on both univariate and multivariate analyses (ß = 5.7; R2 = 0.34; p < 0.01). CONCLUSION: Neither total testosterone nor hypogonadism is associated with a degree of improvement after collagenase clostridium histolyticum treatment.

Association between HPV infection and penile cancer and penile intraepithelial neoplasia: A retrospective observational study.

BACKGROUND: Penile cancer is rising in most European countries. Several risk factors have been identified, namely human papillomavirus (HPV) infection. However, the exact role of HPV in penile cancer carcinogenesis is still unknown. Clarifying the contribution of HPV in penile cancer is crucial as it may improve prevention and treatment strategies. OBJECTIVE: To describe the characteristics of patients with penile cancer and penile intraepithelial neoplasia (PeIN), evaluate the prevalence of HPV-DNA in tumour tissue and identify differences between patients with and without HPV-DNA. METHODS: A retrospective observational study including patients with histological diagnosis of penile squamous cell carcinoma (SCC) or PeIN between 2012 and 2021 in a university hospital was carried out. HPV analysis was performed using Anyplex™ II HPV28 Detection that detects and identifies 28 HPV types. (sensitivity of 95.9%). RESULTS: A total of 25 patients were included. Most of the tumours identified were invasive SCC (n = 11) and SCC in situ (PeIN 3) (n = 8). PeIN1/2 was found in the remaining six patients. HPV-DNA was tested in all tissue specimens and was detected in 18 of them. High risk HPV DNA was identified in all positive HPV samples, except one. HPV types included in the nonavalent HPV vaccine were identified in 16 of the 18 samples positive for HPV-DNA. Stratifying patients according to HPV-DNA detection, we found that patients with HPV-DNA were younger (57.5 years vs. 70 years, p = 0.047), less likely to have phimosis (5.8% vs. 42.9%, p = 0.022) and more likely to have PeIN lesions than invasive SCC (85.7% vs. 27.8%, p = 0.025). CONCLUSION: This study shows a prevalence of HPV-DNA in penile SCC and premalignant lesions of 45.5% and 92.9%, respectively. Identifying HPV involvement in SCC and PeIN pathology has the potential to guide treatment and enhance follow-up strategies.

Differences in overall survival of penile cancer patients versus population-based controls.

PURPOSE: To assess whether 5-year overall survival (OS) of squamous cell carcinoma of the penis (SCCP) patients differs from age-matched male population-based controls. METHODS: We relied on the Surveillance Epidemiology and End Results database (2004-2018) to identify newly diagnosed (2004-2013) SCCP patients. For each case, we simulated an age-matched control (Monte Carlo simulation), relying on the Social Security Administration (SSA) Life Tables with 5 years of follow-up. We compared OS between SCCP patients and population-based controls in a stage-specific fashion. Smoothed cumulative incidence plots displayed cancer-specific mortality (CSM) versus other-cause mortality (OCM). RESULTS: Of 2282 SCCP patients, the stage distribution was as follows: stage I 976 (43%) versus stage II 826 (36%) versus stage III 302 (13%) versus stage IV 178 (8%). At 5 years, OS of SCCP patients versus age-matched population-based controls was as follows: stage I 63% versus 80% (Δ = 17%), stage II 50% versus 80% (Δ = 30%), stage III 39% versus 84% (Δ = 45%), stage IV 26% versus 87% (Δ = 61%). At 5 years, CSM versus OCM in SCCP patients according to stage was as follows: stage I 12% versus 24%, stage II 22% versus 28%, stage III 47% versus 14%, and stage IV 60% versus 14%. CONCLUSION: SCCP patients exhibit worse OS across all stages. The difference in OS at 5 years between SCCP and age-matched male population-based controls ranged from 17% to 61%. At 5 years, CSM accounted for 12% to 60% of all deaths, across all stages.

Extramedullary Plasmacytoma of the Penis as a First Manifestation of Multiple Myeloma: A Case Report.

INTRODUCTION: Plasmacytoma is a rare plasma-cell neoplasm, which includes bone and extramedullary types. While most cases occur in the head and neck, our report presents an unusual case of extramedullary plasmacytoma (EMP) in the penis, emphasizing the diverse locations of this condition. CASE PRESENTATION: An 88-year-old man, post-hydrocelectomy, presented with a palpable penile mass causing urinary symptoms. CT scans revealed a tumor with extracapsular spread and potential urethral involvement. Biopsy confirmed lymphoma, later identified as extramedullary plasmacytoma. A follow-up whole-body CT scan was performed, revealing multiple areas of bone rarefaction of the dens of the axis. His diagnosis has been further specified as multiple myeloma. Treatment with lenalidomide, bortezomib, and dexamethasone led to significant penile tumor reduction and improved voiding symptoms after three cycles. CONCLUSION: A rare case of primary EMP in the penis is reported, with only two documented cases of EMP in this location. The etiology of EMP remains unclear, possibly linked to chronic infection, irritation, or inflammation. EMP typically occurs in soft tissues, commonly in the head and neck, presenting as submucosal masses with symptoms in individuals aged 50-70. Diagnosis requires demonstrating monoclonal plasma cell infiltration and excluding multiple myeloma. While EMPs are often treated with radiotherapy, a patient with bone rarefaction suggestive of multiple myeloma requires first-line chemotherapy. This case highlights the importance of recognizing myeloma-defining events for appropriate treatment.