Exploring the landscape of urinary tract melanomas: A review for pathologists and clinicians.

Melanomas originating within the urinary tract represent a rare and clinically challenging subset of malignancies. Despite extensive research on cutaneous melanomas, urinary tract melanomas remain relatively unexplored, presenting diagnostic dilemmas and limited treatment consensus. In this comprehensive review, we synthesize current knowledge on the epidemiology, risk factors, clinical presentation, histopathological characteristics, and treatment strategies specific to this disease. Enhancing clinical awareness, refining diagnostic approaches, and exploring novel therapeutic interventions hold promise for improving outcomes in this challenging malignancy subset.

Corrigendum: Cardiac infarction caused by PD-1 inhibitor during small cell neuroendocrine carcinoma of the ureter treatment: a case report.

[This corrects the article DOI: 10.3389/fonc.2023.1114397.].

A surprise during hernia surgery: inguinoscrotal megaureter.

BACKGROUND: Ureteroinguinal herniation is a rare occurrence that is typically diagnosed during the surgical repair of inguinal hernias. CASE PRESENTATION: We present the case of a 4-year-old male who underwent inguinal hernia repair, during which a megaureter was discovered within the hernia sac. The surgical intervention included high ligation of the hernial sac and repositioning of the ureter back into the retroperitoneum. Postoperative investigations confirmed a diagnosis of primary non-refluxing and nonobstructive megaureter. CONCLUSION: Although ureteral herniation is rare in infants, it is crucial to remain vigilant about the possibility of encountering the ureter during hernia repair to prevent potential ureteral injuries. Additionally, any associated urinary tract anomalies should be thoroughly investigated and ruled out.

Laparoscopic Ureteral Reconstruction in Children with Retrocaval Ureter: A Modern Single Center Retrospective Study.

Purpose: This study aims to report our experience in the treatment of children with retrocaval ureter (RCU) using laparoscopic ureteral reconstruction surgery. Patients and Methods: We retrospectively collected clinical data from 10 pediatric patients with RCU who underwent laparoscopic surgery at our hospital from April 2010 to April 2022. All patients underwent comprehensive preoperative radiological assessment and were diagnosed with RCU, subsequently undergoing laparoscopic ureteral reconstruction. Patient demographics, surgical data, and postoperative outcomes were recorded. Regular follow-ups were conducted postoperatively, evaluating clinical symptoms and radiological results. Results: The median age of the 10 patients was 8.8 years (range, 6-14 years). All surgeries were successfully performed laparoscopically without the need for open conversion, with an average surgical time of 153.3 minutes (range, 120-243 minutes). Intraoperative bleeding was minimal and no blood transfusions were required. No intraoperative complications were observed. The average hospital stay for the patients was 5.3 days (range, 4-7 days) and the Double-J (D-J) stent was removed 6 weeks postoperatively. Follow-up ultrasound results at 3 and 6 months postoperatively showed a reduction in renal pelvic dilatation, and all patients experienced significant relief of clinical symptoms related to flank and abdominal discomfort. Conclusion: Laparoscopic reconstruction for RCU demonstrates good feasibility and effectiveness in pediatric patients, offering a minimally invasive treatment option for the management of RCU in children.

Deep pelvic endometriosis causing ureteral obstruction.

Endometriosis is a chronic disease characterized by the presence and growth of endometrial glands and stroma outside of the uterine cavity. The pathogenesis is unclear, but a common theory attributes the condition to retrograde menstruation into the peritoneal cavity via the fallopian tubes. Hormonal influence causes these ectopic tissues to undergo cyclical bleeding, resulting in subsequent inflammation and scar tissue formation; however, it can affect postmenopausal women. In rare instances, endometriotic lesions can obstruct the ureter and result in hydroureteronephrosis and subsequent loss of renal function. This condition presents with nonspecific symptoms and is known as an often-silent disease, resulting in challenging and delayed preoperative diagnosis. In this article, we report the case of an asymptomatic 65-year old female who was diagnosed with deep pelvic endometriosis, which obstructed the right distal ureter. We focus on optimizing diagnosis and management through the application of radiological imaging modalities, specifically computed tomography (CT) and magnetic resonance imaging (MRI).

Ultrasound findings in 34 newborn foals with uroperitoneum.

BACKGROUND: Uroperitoneum is a typical disease of the newborn foal, which occurs rarely but regularly. Ultrasonography is considered the most important imaging method for diagnosing this disease. Thus far, only one older case series comprising 31 foals suffering from uroperitoneum has systematically listed results of ultrasound examinations. OBJECTIVE: This paper presents the findings of an ultrasonographic examination of 34 foals with uroperitoneum in order to inform future interpretation of ultrasonographic data in suspected uroperitoneum cases. METHOD: Ultrasonographic data of 34 neonatal foals up to the age of 14 days diagnosed with uroperitoneum between 2006 and 2022 were analysed. RESULTS: Most foals demonstrated highly increased levels of free (97%), anechogenic (91%) fluid in the abdomen. Although the urinary bladder was frequently visible (50%), bladder wall discontinuity was only occasionally detectable (18%). CONCLUSION: Transabdominal ultrasonography has proved to be a very reliable imaging method for diagnosing suspected uroperitoneum. It is recommended that it be used in every case of suspected uroperitoneum in order to exclude differential diagnoses.

Ureteral Metastasis From Prostate Cancer: A Report of Two Cases.

Prostate adenocarcinoma (PCa) is the second most common cause of cancer in men, but metastases to the ureter are exceedingly rare. Here, we present two cases with differing clinical symptoms and treatment courses but ultimately the same diagnosis. The two cases presented here had differing clinical presentations: one with lower urinary tract symptoms and the other with hydronephrosis. Systemic therapy with a luteinizing hormone-releasing hormone (LHrH) agonist appears to help with clinical outcomes in both cases reported here. Although such cases are extremely rare, consideration as a differential and early detection can impact a patient's clinical outcomes. For patients with PCa that present with obstructive urinary symptoms, there may be a clinical benefit to perform a thorough metastatic work-up for seeding to other parts of the urinary tract.

Mechanical characterization of porcine ureter for the evaluation of tissue-engineering applications.

Introduction: Clinics increasingly require readily deployable tubular substitutes to restore the functionality of structures like ureters and blood vessels. Despite extensive exploration of various materials, both synthetic and biological, the optimal solution remains elusive. Drawing on abundant literature experiences, there is a pressing demand for a substitute that not only emulates native tissue by providing requisite signals and growth factors but also exhibits appropriate mechanical resilience and behaviour. Methods: This study aims to assess the potential of porcine ureters by characterizing their biomechanical properties in their native configuration through ring and membrane flexion tests. In order to assess the tissue morphology before and after mechanical tests and the eventual alteration of tissue microstructure that would be inserted in material constitutive description, histological staining was performed on samples. Corresponding computational analyses were performed to mimic the experimental campaign to identify the constitutive material parameters. Results: The absence of any damages to muscle and collagen fibres, which only compacted after mechanical tests, was demonstrated. The experimental tests (ring and membrane flexion tests) showed non-linearity for material and geometry and the viscoelastic behaviour of the native porcine ureter. Computational models were descriptive of the mechanical behaviour ureteral tissue, and the material model feasible. Discussion: This analysis will be useful for future comparison with decellularized tissue for the evaluation of the aggression of cell removal and its effect on microstructure. The computational model could lay the basis for a reliable tool for the prediction of solicitation in the case of tubular substitutions in subsequent simulations.

Evaluation of the benefit of indocyanine green as an educational and practical tool for ureteral identification in laparoscopic pelvic surgery: a cross-sectional study.

BACKGROUND: Indocyanine green (ICG) is a visible near-infrared fluorescent dye. Several studies have reported its benefit in identifying important anatomical structures, tissue vascularization, and sentinel lymph nodes in the case of tumors. Studies have shown that ICG is critical and safe in gynecologic surgeries. However, research on how ICG dye can help surgeons in laparoscopic surgeries correctly identify the course of the ureter has yet to be further investigated. METHOD: This cross-sectional study enrolled 62 gynecology attending and resident surgeons who were asked to identify the course of the ureter on images of laparoscopic surgeries. The results were then compared with images in which ICG dye highlighted the course of the ureter. The purpose of this study was to detect the ability of surgical assistants and residents to adequately identify the course of the ureter in laparoscopic pelvic surgeries. RESULTS: No statistically significant differences were found in terms of year of residency, years of experience, number of laparoscopic procedures attended, and correct identification of ureter course. ICG proved useful in identifying the correct ureteral trajectory. CONCLUSIONS: ICG can be a valuable tool to improve the correct identification of ureters and improve surgical outcomes.

Intrauterine Contraceptive Device Migrated in the Urinary Tract: Case Report and Extensive Literature Review.

The migration or translocation of an intrauterine device (IUD) in the urinary tract is a rare event. Here, we present the case of a 55-year-old woman who accidentally discovered the ectopic presence of an IUD following a radiological examination for pelvic pain caused by a lumbar discopathy. Over the years, the patient had several IUDs inserted without being able to specify which one had migrated. The removal of the IUD was performed laparoscopically with the minimum resection of the bladder wall and the subsequent cystorrhaphy. The evolution of the patient was favorable. To better analyze these events, we conducted an all-time extensive electronic search of the PubMed database and identified 94 eligible articles, with a total of 115 cases. The literature analysis on the IUD migrations shows either the simultaneous existence of the second IUD or of a maximum number of up to two IUD insertions during the life of patients. Thus, in the presented case, we identified five IUD insertions over time, which explained the chronic inflammatory process by forming an important mass of adherents that included the urinary bladder, uterus, omentum, sigmoid colon, and abdominal wall. Therapeutic management must be adapted to each case depending on the intra/extravesical location of the migrated IUD evaluated by imaging.

Distinguishing Physiological Ureter Uptake From an Involved Lymph Node in Staging Prostate-Specific Membrane Antigen (PSMA) Scans: Implications for Radiation Planning.

Prostate-specific membrane antigen (PSMA) imaging has become a mainstay diagnostic tool in staging unfavorable primary prostate cancer (PC) and identifying sites of recurrence in previously treated PC. One of the biggest pitfalls of PSMA imaging is rapid radionucleotide excretion in the urine via the​ kidneys, ureters, and bladder.​ The positron-emission tomography (PET) images obtained show increased radiotracer activity in these structures, which can occlude or even mimic true malignant disease. We describe the diagnostic challenges encountered in differentiating benign versus malignant disease with PSMA scans. A 78-year-old male presented ​to our outpatient radiation oncology office ​with high-risk prostate cancer. His medical history was significant for ulcerative colitis (UC). Magnetic resonance imaging (MRI) revealed an enlarged prostate and a Prostate Imaging Reporting and Data System (PI-RADS) class 4 lesion. A subsequent transperineal biopsy confirmed unilateral Gleason 8 adenocarcinoma. A PSMA PET scan was read as increased uptake in the right prostate and a left external iliac node. The patient, having been initially informed of a positive lymph node metastasis, sought a second opinion,​resulting in​​ ​a CT urogram that revealed physiologic ureteral uptake. We were thus able to avoid lymph node radiation and morbidity to the surrounding bowel, already chronically inflamed with ulcerative colitis. This study ​demonstrates the ​potential for misinterpretation of PSMA uptake in the ureter as lymph node metastases. We discuss how peri-uretic activity can hinder accurate visualization of pelvic lymph node metastases. This study highlights the need for careful image interpretation of PSMA uptake patterns in order to avoid diagnostic errors and unnecessary radiation to ​at-risk​​ ​organs in prostate cancer management.

Surgical Management of Bilateral Single-System Ectopic Ureters (BSSEUs) in a Pediatric Patient: A Report of a Rare Case and Literature Review.

Bilateral single-system ectopic ureters (BSSEUs) are among the rarest entities encountered in pediatric urology. A BSSEU occurs when the ureteric buds originate cranially from the mesonephric ducts, causing a delay in their integration into the urogenital sinus. It presents as continuous incontinence in females, whereas symptoms like infection and discomfort are present in males. We describe a case involving a BSSEU opening into the vagina and urethra, with the patient experiencing continuous urinary incontinence, and its diagnosis and management. Here, We discuss a rare case of a four-year-old girl exhibiting continuous urinary incontinence or dribbling associated with recurrent urinary tract infections (UTIs) attributed to bilateral ectopic ureters. Imaging modalities, including contrast-enhanced computed tomography(CECT) and MRI, revealed the presence of BSSEUs accompanied by hydroureteronephrosis. The condition was managed with prompt surgical intervention involving bilateral ureteric reimplantation. Subsequent to the procedure, the patient experienced a significant improvement in continence mechanism and bladder capacity, obviating the requirement of urinary diversion procedure appendicovesicostomy or bladder neck reconstruction. Notably, while BSSEUs are an uncommon presentation, their timely and appropriate management is paramount in preventing potential renal damage. This case underscores the significance of vigilant monitoring and proactive intervention in addressing such complex urological anomalies in pediatric patients.

Contemporary status of diagnostic endoluminal ultrasound and optical coherence tomography in the ureter.

Objective: To evaluate via a review of published literature, the efficacy of endoluminal ultrasound (ELUS) and optical coherence tomography (OCT) in the following ureteric diseases: urolithiasis, upper tract urothelial carcinoma, stricture disease and pelvic-ureteric junction obstruction (PUJO). Patients and methods: Ureteric high-frequency ELUS provides 360° imaging, to a depth of 20 mm, and has been demonstrated to assess ureteric stricture length, degree of fibrosis and aetiology. OCT produces high-quality images with a penetration depth of 2 mm. ELUS has proven to be useful at the time of endopyelotomy for PUJO as it can identify crossing vessels, some not detectable on CT angiography, allowing the urologist to avoid these when making their incision. Ureteric ELUS may be utilised for submucosal ureteric stones as they are highly visible. Endoluminal ultrasound may be deployed in the case of known sub-mucosal urolithiasis when the ureter appears stone-free. It may help identify sub-mucosal stones or stones within diverticulum. Results: Endoluminal ultrasound has been analysed for its use in determining muscle-invasive urothelial carcinoma of the ureter. The PPV for ≥pT2 was only 16.7% in one study of six patients with MIBC and 76.2% in 21 patients with

Difference of oncological efficacy between two immune checkpoint inhibitors following first-line platinum-based chemotherapy in patients with unresectable, metastatic, advanced urothelial carcinoma: a multicenter real-world Japanese cohort.

BACKGROUND: Maintenance avelumab is currently recommended for patients with unresectable and/or metastatic (mUC) achieving at least stable disease (SD) on first-line platinum-based chemotherapy (1L-CT). Pembrolizumab is an alternative therapeutic avenue for this patient cohort in clinical practice. We investigated real-world data, focusing on the correlation between response to 1L-CT and oncological efficacy of subsequent immune checkpoint inhibitor (ICI) therapy with avelumab or pembrolizumab. METHODS: A multicenter database registered 626 patients with mUC diagnosed from 2008-2023; among these, 175 receiving 2-6 cycles of 1L-CT followed by ICI therapy. Patients were categorized based on response to 1L-CT using the Response Evaluation Criteria in Solid Tumors (v1.1). Objective response rate on ICI, progression to ICI-free survival (ICI-PFS), and overall survival from start of 1L-CT were compared between avelumab-treated and pembrolizumab-treated patients in each response subgroup. RESULTS: ICI-PFS was significantly longer in patients achieving partial response on 1L-CT and subsequently receiving pembrolizumab compared to those receiving avelumab. Notably, patients achieving SD on 1L-CT and subsequently receiving pembrolizumab manifested significantly higher objective response rate (14% and 41%, respectively) and prolonged ICI-PFS relative to those receiving avelumab. In contrast, overall survival did not delineate difference between patients treated with avelumab versus pembrolizumab. Similar findings were discerned in the subanalysis of patients having favorable SD (tumor shrinkage, from - 29 to 0%) and unfavorable SD (tumor enlargement, from + 1 to + 19%) on 1L-CT. CONCLUSIONS: Our study provides real-world evidence regarding difference of oncological efficacy between maintenance avelumab and subsequent pembrolizumab in patients with mUC who achieved partial response or SD on 1L-CT.

A case of a blind-ending right ureter first identified intraoperatively during total laparoscopic hysterectomy for uterine adenomyosis and fibroids in a woman with severe ipsilateral kidney hypoplasia.

Detecting ureteral injury-a serious intraoperative and postoperative complication of hysterectomy-is a high level of difficulty if ureteral malformations are not identified preoperatively. A 39-year-old Japanese woman underwent total laparoscopic hysterectomy for uterine adenomyosis. During surgery, ureteral peristalsis was absent on the right side, whereas the left ureter was visible under the peritoneum. Transabdominal ultrasonography failed to locate the right kidney, with cystoscopy showing no flow from the right ureteral orifice. The ureteral tunnel was identified by tracing the vascular path of the internal iliac and uterine arteries, confirming that the corded tissue was the right ureter. Postoperative contrast-enhanced CT revealed severe right kidney atrophy with no contrast effect or connected ureter. Based on intraoperative laparoscopy and postoperative examination, a diagnosis of a unilateral ureteral scar with a proximal blind end and ipsilateral renal dysgenesis was established, marking the first reported instance of endoscopic visualization of this anomaly. In addition to normal pelvic anatomy, surgeons must consider embryological abnormalities to prevent intraoperative complications.

Ectopic Kidney with an Ectopic Ureter Masquerading Adnexal Mass: A Case Report and Literature Review.

An ectopic kidney is a rare congenital defect that is often asymptomatic, but can be incidentally discovered during imaging examinations. Moreover, the morphological characteristics and laboratory features of ectopic kidneys are nonspecific, which may lead to misleading diagnostic approaches, particularly when there are additional factors, such as infection, obstruction, or other anomalies. A 43-year-old female presented with a mass in the left adnexal area. She had septate uterus and a history of congenital urinary incontinence. Ultrasound and MRI findings indicated that the mass was a cyst originating from the ovary. However, it is possible that the lump was derived from the urinary system. To confirm the diagnosis, laparoscopy was performed, followed by pathological examination, which confirmed the presence of an ectopic kidney with a single-system ectopic ureter. The patient underwent nephroureterectomy, and her symptoms successfully resolved, leading to a favorable prognosis. This case report highlights a rare case involving an ectopic kidney with a vaginal ectopic ureter that initially presented as an adnexal cyst and caused urinary dribbling. This case emphasizes the importance of early recognition and accurate diagnosis in women with similar symptoms.

Immunoglobulin G4 disease-related retroperitoneal fibrosis: A series of five cases.

Immunoglobulin G4 (IgG4)-related disease has the potential to impact any part of the body, including the walls of large- and medium-sized blood vessels and the ureters. While histopathologic examination is currently the standard method for identifying organ involvement and diagnosing IgG4-related disease (IgG4-RD), obtaining biopsy or surgical samples from vessel or ureteral walls is challenging. Given that patients may display only mild symptoms, non-invasive imaging plays a vital role in both diagnosing and managing IgG4-related diseases. Multidetector CT scans are valuable in establishing the primary diagnosis, identifying anatomical landmarks and assessing their relationships. Involvement of the genitourinary organs, such as the ureter, bladder, urethra, and male and female reproductive organs in IgG4-RD, is infrequent when compared to kidney involvement. The imaging findings may include the presence of a localised mass within or surrounding the affected organ or a generalised enlargement of the organ. This report includes cross-sectional images of five cases of IgG4-RD involving large- and medium-sized blood vessels (the aorta and superior mesenteric artery) and the ureters. Contribution: This case series provides insight into the various imaging appearances of IgG4-related retroperitoneal organ involvement and helps differentiate it radiologically from retroperitoneal fibrosis.

Ectopic Ureter Opening in Vagina: A Rare Cause of Nonfunctional Kidney and Urinary Incontinence in a Pediatric Patient.

An ectopic ureter is a condition characterized by a ureter, whether single or duplex, that fails to open in the trigone area of the urinary bladder but instead drains outside of it. This anomaly arises congenitally due to abnormal migration of the ureteric bud during its insertion into the urinary bladder. Here, we present a case involving an ectopic ureter draining into the vagina, with continuous urinary incontinence. We discuss the diagnosis, evaluation, and management of urinary incontinence in a female because of an ectopic ureter. A 9-year-old girl child presented with a continuous urinary leak or incontinence requiring the use of one to two pads per day that progressively became wetter throughout the day. Physical examination revealed a normal urethral meatus and vagina without obvious visible dribbling of urine at the introitus. CT urography showed significant dilation of the right ureter, causing hydroureter and ectopic insertion of the tortuous right ureter near the external urethral orifice at the vaginal vestibule, along with an atrophic right kidney. A DTPA (diethylenetriamine pentaacetate) scan indicated the nonfunctional status of the right kidney. The patient underwent a right nephroureterectomy, leading to a complete resolution of urinary incontinence. Ectopic ureter causing nonfunctional kidney and urinary leak or incontinence is rare. This case emphasizes the importance of a comprehensive diagnostic workup for achieving a better prognosis and initiating early treatment of ectopic ureter.

Management of a rare symptomatic retrocaval ureter: a case report with review of literature.

Retrocaval ureter is a rare congenital vascular anomaly with an incidence of 0.13%, leading to the passage of the right ureter behind the inferior vena cava and then turning around it to attain its lateral position. The condition is usually associated with obstruction in the right kidney and proximal ureter leading to symptoms like dull aching pain in the flanks, recurrent episodes of urinary tract infections, and recurrent stone formation. The patient presented with recurrent episodes of burning micturition and pain in the right flank for the past 6 months. A contrast-enhanced computed tomography kidney-ureter-bladder was done to diagnose the condition. The patient was managed by open pelviureteric anastomosis lateral to the inferior vena cava, thus eliminating the obstruction on the ureter. The patient has had an uneventful postoperative follow-up. Retrocaval ureter is a rare condition and should be clinically suspected in cases of hydronephrosis where other causes have been ruled out. Different approaches can be used to correct the anomaly. In this case report, an open transperitoneal intraabdominal approach has been used.

Minimally invasive versus open ileal ureter with ileocystoplasty: comparative outcomes and 5-year experience.

PURPOSE: To present the experience of ileal ureter with ileocystoplasty (IUC), and compare the outcomes of IUC in minimally invasive procedures to open procedures. PATIENTS AND METHODS: From December 2017 to April 2023, twenty patients underwent IUC in open or minimally invasive (including laparoscopic and robotic) procedures. The baseline characteristics, perioperative data and follow-up outcomes were collected. Success was defined as relief of clinical symptoms, stable postoperative serum creatine and absence of radiographic obstruction. The perioperative and follow-up outcomes of open procedures and minimally invasive procedures were compared. RESULTS: The etiology included pelvic irradiation (14/20), urinary tuberculosis (3/20) and surgical injury (3/20). Bilateral ureter strictures were repaired in 15 cases. The surgeries conducted consisted of open procedures in 9 patients and minimally invasive procedures in 11 patients. Compared to open procedures, minimally invasive surgeries had less median estimated blood loss (EBL) (100 ml vs. 300 min, p = 0.010) and shorter postoperative hospitalization (27 d vs. 13 d, p = 0.004). Two patients in the open group experienced grade 3 complications (sigmoid fistula and acute cholecystitis in one patient, and pulmonary embolism in another patient). Over a median follow-up period of 20.1 months, the median bladder functional capacity was 300 ml, with a 100% success rate of IUC. CONCLUSION: IUC is feasible in both open and minimally invasive procedures, with acceptable complications and a high success rate. Minimally invasive procedures can have less EBL and shorter postoperative hospitalization than open procedure. However, prospective studies with larger groups and longer follow-up are needed.