Successful treatment with enfortumab-vedotin of metastatic signet ring cell cancer expressing nectin-4 and originating from the bladder.

Introduction: As an aggressive adenocarcinoma phenotype, primary signet ring cell carcinoma of the urinary bladder is an extremely rare variant. The prognosis of metastatic signet ring cell carcinoma of the urinary bladder is extremely poor and the clinical course for its specific pathogenesis remains unelucidated. Case presentation: A 64-year-old Japanese male patient was diagnosed with invasive urothelial carcinoma with glandular differentiation of a signet ring cell-type with pT4aN0M0, and he was eventually diagnosed with metastatic signet ring cell carcinoma of the urinary bladder. He was initially responsive to systemic combination induction chemotherapy of S-1 and cisplatin followed by avelumab switch maintenance therapy; however, signet ring cell carcinoma of the urinary bladder relapse occurred in the pathological findings of a biopsy from the right thigh. Immunohistochemical analysis of this specimen identified strong positive staining for nectin-4 and, following enfortumab-vedotin treatment, the patient showed a good response. Conclusion: We thus describe a rare case of metastatic signet ring cell carcinoma of the urinary bladder with nectin-4 expression diagnosed by a biopsy of a metastatic site.

Comparison of Percutaneous Renal Access Between Robot-Assisted Fluoroscopy Guidance Using the Bi-Plane Method and Ultrasound Guidance: A Multicenter Randomized Control Benchtop Study.

Purpose: To evaluate the efficacy of supine percutaneous renal access by robot-assisted (RA) fluoroscopy and ultrasound (US) guidance in terms of procedural outcomes and surgeon workload. Methods: We conducted a multicenter, randomized, controlled benchtop study involving 32 urologists using a renal phantom model. RA puncture was performed using the developed version of automated needle targeting with X-ray (ANT-X), which determines the direction of the needle. US puncture was performed under US guidance. The primary endpoint was the single-puncture success rate, and the secondary outcomes were the procedural time for each step, time of fluoroscopic exposure, and workload assessment. Results: The single-puncture success rates were 90.6% and 56.3% for RA and US punctures, respectively (p < 0.01). In RA puncture, the median device setup time was 120 seconds longer, the median total procedural time was 100 seconds longer, the median time of fluoroscopic exposure was 40 seconds longer, the median needle puncture time was 17 seconds shorter, and the distance from the target sphere was 1 cm shorter than those in US puncture (all p < 0.01). The mental and physical task workload, effort required by the surgeons, frustration felt by the surgeons, and overall National Aeronautics and Space Administration Task Load Index scores were lower in the RA puncture group than in the US puncture group (p = 0.01, p = 0.046, p < 0.01, p = 0.021, and p ≤ 0.01, respectively). Conclusions: RA puncture using ANT-X, which can also be used for puncture in the supine position, offers advantages over renal puncture in terms of accuracy and surgical workload.

Efficacy of Robot-Assisted Ureteroureterostomy in Patients with Complex Ureteral Stricture after Ureteroscopic Lithotripsy.

BACKGROUND: Ureteral stricture (US) postureteroscopic lithotripsy (URSL) has emerged as a severe complication with the widespread use of laser technology. Furthermore, managing a complex US is challenging. Therefore, this study evaluated the efficacy of robot-assisted ureteroureterostomy (RAUU) in addressing US post-URSL and analyzed the pathology of transected ureteral tissues to identify the risk factors for US. METHODS: we conducted a prospective cohort study on patients who underwent RAUU for URSL-induced US from April 2021 to May 2023. RESULTS: A total of 14 patients with a mean age of 49.8 years were included in this study. The mean stricture length on radiography was 22.66 ± 7.38 mm. Nine (64.2%) patients had experienced failure with previous interventions. The overall success rate was 92.9%, both clinically and radiographically, without major complications, at a mean follow-up of 12.8 months. The pathological findings revealed microcalcifications and a loss of ureteral mucosa in 57.1% and 28.6% of patients, respectively. CONCLUSIONS: The RAUU technique shows promise as a viable option for US post-URSL in appropriately selected patients despite severe pathological changes in the ureter. Therefore, the migration of microcalcifications to the site of ureteral perforation may be a significant factor contributing to US development.

Impact of pelvicalyceal anatomical variation on surgical outcomes of endoscopic combined intrarenal surgery.

Objectives: The objective of this work is to investigate the impact of the pelvicalyceal anatomical system (PCS) on calyceal stone formation and surgical outcomes of endoscopic combined intrarenal surgery (ECIRS) for renal and/or proximal ureteral stones with a diameter >15 mm. Patients and methods: PCS was classified as Type I (single pelvis) or Type II (divided pelvis) according to the simple anatomical Takazawa classification. Using prospectively collected data from January 2016 to April 2020, 219 patients were retrospectively reviewed. After excluding patients who underwent a staged procedure, had hydronephrosis greater than grade 2, prior nephrostomy tubes, and failed to access the renal collecting system, 115 patients (Type I: 81, Type II: 34) were included, and the distribution of calyceal stones and surgical outcomes in ECIRS were compared between Types I and II PCS. Results: The median number of renal stone calyces in the Type II group was significantly more than that in the Type I group (p = 0.016). In particular, the Type II group possessed more upper stone calyces. Multivariate logistic regression analysis revealed that Type II PCS was associated with an increased odds ratio (OR) for the presence of upper stone calyces (OR: 2.93, p = 0.018). The stone-free (SF) status at 1 month after surgery, confirmed by abdominal plain radiography, was significantly higher in the Type I group compared with that in Type II (67.9% vs. 39.4%, respectively; p = 0.006). The requirement for additional surgical interventions was significantly higher in the Type II group compared with that in Type I (35.4% vs. 7.4%, respectively; p < 0.001). Multivariate analysis revealed that the number of stone calyces (OR: 4.26; p = 0.001) and Type II PCS (OR: 3.43; p = 0.009) were independent predictors of residual stones after ECIRS. Conclusion: We first revealed that the anatomic properties of PCS play a role in both upper calyceal stone formation and in the success of the ECIRS procedure. Because the SF rate in Type II PCS was significantly lower than that in Type I PCS, additional percutaneous nephrolithotomy tracts might be required, even for ECIRS.

Pelviureteric junction obstruction of the ipsilateral kidney caused by hydronephrosis secondary to crossed fused renal ectopia.

Introduction: Crossed fused renal ectopia is rare and usually asymptomatic. However, it is associated with urological anomalies. Case presentation: A 15-year-old Japanese boy was transported to our hospital with right abdominal pain and hematuria after a soccer ball hit his right abdomen. Computed tomography revealed right hydronephrosis beyond the center of the body and no left kidney. Percutaneous nephrostomy was performed immediately, and a pyeloplasty was scheduled for 5 months later. Right hydronephrosis was noted to have been caused by left pelvic expansion due to a crossed fused ectopic kidney (secondary to a left pelviureteric junction obstruction). Subsequently, a left dismembered pyeloplasty was performed. Twenty-four months later, pain and hematuria were absent, and the creatinine level was 1.1 mg/dL. Ultrasonography revealed a shrunken right kidney. Conclusion: We encountered a unique urological anomaly with crossed fused renal ectopia. Comprehensive anatomical evaluation before surgery is important for maintaining long-term renal function.

Status epilepticus in a patient with intractable epilepsy caused by renal colic due to a ureter stone.

INTRODUCTION: Epilepsy has a variety of seizure-inducing factors. Epileptic seizures caused by renal colic are extremely rare. CASE PRESENTATION: A 22-year-old woman with intractable epilepsy was brought to our hospital as an emergency case, because of vomiting and status epilepticus. She had implanted a vagus nerve stimulator in the left anterior chest at the age of 20 years. Computed tomography showed a ureter stone in the right distal ureter. On the second day of hospitalization, ureteroscopic lithotripsy was performed under general anesthesia. The patient's seizures were controlled to a frequency of once a month or less in the four months after discharge. CONCLUSION: We encountered a rare case of the frequency of status epilepticus increased by renal colic due to a ureter stone. Ureteroscopic lithotripsy was effective in controlling the frequency of status epilepticus increased by renal colic.