Robot-assisted Partial Nephrectomy With Selective Artery Clamping for Renal Cell Carcinoma in Horseshoe Kidney.

BACKGROUND: Robot-assisted partial nephrectomy (RAPN) has become the standard treatment for small renal tumors, including highly complex cases. However, applying RAPN to renal tumors in the horseshoe kidney (HSK) is clinically challenging due to malformations and complex blood supply. Herein, we present two cases of RAPN in patients with HSK treated using selective artery clamping methods. CASE REPORTS: A 61-year-old male with a 15 mm renal tumor located on the upper pole of the right HSK was referred to our Department. The patient underwent RAPN via the transperitoneal approach, following a three-dimensional computed tomography (3D-CT) assessment. Additionally, before surgery, we confirmed which renal arteries would be clamped in surgery by examining the kidney regions supplied by each renal artery. The second patient referred to our Department, a 45-year-old male, had a 46 mm renal tumor located on the isthmus of the HSK. His tumor received blood supply from two renal arteries, with the bilateral collecting systems converging and forming a ureter on 3D-CT. The patient underwent RAPN through an intraperitoneal approach in the semi-lateral position, with port placement lower than in standard RAPN. Pathological examinations revealed clear-cell renal cell carcinoma with negative surgical margins in both cases. Both patients had no recurrences or metastases at 53 and 13 months post-surgery, respectively. CONCLUSION: We present cases successfully treated with RAPN with selective artery clamping methods for HSK using 3D-CT without encountering complications, even in isthmus tumors.

Safety of Docetaxel in a Patient with Metastatic Castration-Resistant Prostate Cancer After Kidney Transplantation: A Case Report.

BACKGROUND: There are limitations in treating advanced prostate cancer (PC), especially castration-resistant (CR) cases, in renal transplant recipients (RTRs). We describe the case of RTR with metastatic CRPC (mCRPC) treated with docetaxel. CASE REPORT: A 60-year-old man with end-stage renal disease due to autosomal-dominant polycystic kidney disease (ADPKD) underwent living-related kidney transplantation. A year later, he was diagnosed with PC (prostate-specific antigen level: 998 ng/mL). Prostate biopsy revealed prostatic adenocarcinoma with a Gleason score of 4 + 4 = 8. Radiographic examination revealed seminal vesicle invasion and multiple bone and lymph node metastases. Combined androgen blockade therapy was initiated; however, the patient was diagnosed with CRPC 6 months later. Triweekly docetaxel therapy was administered 28 months after diagnosis. The patient successfully completed 7 cycles of this therapy without major adverse events. However, after the 7th cycle, he developed a high fever caused by an infection of ADPKD-associated renal cysts. Therefore, docetaxel was discontinued, and enzalutamide was started, followed by abiraterone, but without any effect. We then introduced cabazitaxel but discontinued it because of hepatic dysfunction. Hence, the patient underwent a docetaxel rechallenge. He was administered the PEGylated form of the recombinant human granulocyte colony-stimulating factor for neutropenia prophylaxis. After 6 cycles of rechallenge docetaxel therapy, the patient accidentally fell, resulting in a cervical spine fracture and subsequent death due to respiratory failure. CONCLUSIONS: Docetaxel can be safely delivered to patients with CRPC after renal transplantation who are taking oral immunosuppressants. It can be a good treatment option for them.

Advanced Renal Cell Carcinoma With Inferior Vena Cava Thrombus Treated With a Combination of Preoperative Lenvatinib and Pembrolizumab.

BACKGROUND/AIM: Lenvatinib plus pembrolizumab combination therapy is a safe and effective treatment for patients with advanced renal cell carcinoma (RCC). However, there are no reports of the use of lenvatinib and pembrolizumab combination therapy for RCC with an inferior vena cava (IVC) tumor thrombus. Herein, we describe a case in which pembrolizumab and lenvatinib combination therapy was effectively used to treat RCC with the IVC tumor thrombus extending to the right atrium. CASE REPORT: A 73-year-old man was diagnosed with a right renal tumor with the IVC tumor thrombus extending to the right atrium and multiple pulmonary metastases (cT3cN0M1). Using a computed tomography-guided renal tumor biopsy, the tumor was diagnosed as clear cell RCC. The International Metastatic RCC Database Consortium risk classification was poor according to three risk factors, and lenvatinib and pembrolizumab combination therapy was initiated. The primary renal tumor shrunk, the IVC tumor thrombus that reached the right atrium was reduced from level 4 to level 2, and the lung metastases disappeared 4 months after treatment initiation. Thereafter, a robot-assisted deferred cytoreductive nephrectomy was successfully performed. Pathologically, owing to the preoperative combination therapy, most of the tumor tissue was necrotic; however, some viable cells were present in the primary tumor and IVC tumor thrombus. Eight months following the operation, the patient remains recurrence-free. CONCLUSION: Treatment with lenvatinib and pembrolizumab combination therapy led to tumor shrinkage and allowed robot-assisted nephrectomy in a patient with advanced RCC with the IVC tumor thrombus extending to the right atrium, corroborating the efficacy of the treatment.

Clinical Course of Candidate Renal Transplant Recipients Diagnosed With Prostate Cancer During Pre-transplant Screening Test.

BACKGROUND/AIM: Occasionally, candidate renal transplant recipients (RTRs) are incidentally diagnosed with prostate cancer (PCa) during pre-transplant screening examinations; however, their clinical course remains unclear. This study aimed to clarify the clinical course of RTR diagnosed with PCa during pre-transplant screening tests. PATIENTS AND METHODS: Between April 2008 and April 2022, 15 candidates for RTRs were newly diagnosed with PCa during the screening test. We analyzed the patients' treatment choices, initial treatment results, waiting duration for renal transplantation, and whether they finally underwent transplantation. RESULTS: The median patient age was 64 years (range=52-75 years). The median prostate-specific antigen level was 6.9 ng/ml (5.2-56.9 ng/ml). According to D'Amico risk stratification, one, 10, and four patients were at low, intermediate, and high risk, respectively. As for treatment choice, 13 patients chose surgery. Moreover, intensity-modulated radiotherapy and hormone therapy were chosen by one patient each. Of these, seven patients underwent transplantation, with a median waiting time from initial treatment to transplantation of 20.3 months (9.2-40.0 months). One patient discontinued transplantation owing to poor cancer control, four patients had donor issues (change in mind, aging, or disease), and one patient waited because pathological findings revealed locally invasive cancer. CONCLUSION: PCa diagnosis in candidate RTRs during the pre-transplant screening test impacts the candidate's clinical course.

Long-time Survival of a Renal Transplant Recipient With Metastatic Mucinous Tubular and Spindle Cell Carcinoma: A Case Report.

BACKGROUND/AIM: Mucinous tubular and spindle cell carcinoma (MTSCC) of the kidney is a rare histological type of renal cell carcinoma (RCC). There are few reports of MTSCC occurring in renal transplant recipients (RTRs). The aim of this study was to report a case of long-term survival of a RTR with metastatic MTSCC of the kidney with sarcomatoid changes. CASE REPORT: A 53-year-old male with a left retroperitoneal tumor was referred to our department. He had been receiving hemodialysis since 1991 and underwent kidney transplantation in 2015. Computed tomography (CT) revealed suspected RCC, and a radical nephrectomy was performed in June 2020. Pathological findings revealed MTSCC with sarcomatoid changes. After the surgery, multiple metastases appeared in the bilateral adrenals, skin, para-aortic lymph nodes, muscles, mesocolon, and liver. We treated the patient with metastasectomy, radiation therapy, and sequential systemic therapy with tyrosine kinase inhibitors (TKI). Two years after the initial surgery, the patient died of cancer while controlling its progression. CONCLUSION: We report a RTR with aggressive and metastatic MTSCC with sarcomatoid changes, resulting in a longer survival time relative to multimodal therapy.

Efficacy of Combined Pembrolizumab and Pelvic Radiotherapy for Bladder Cancer With Rectal Metastases.

BACKGROUND/AIM: Rectal metastases from urothelial carcinoma (UC) are extremely rare with poor prognosis when treated with gemcitabine and cisplatin (GC) chemotherapy, radiation therapy, and total pelvic exenteration. Long-term survival has not been observed in patients treated with GC chemotherapy, radiation therapy, or total pelvic resection. However, there have been no reports on the efficacy of pembrolizumab therapy for this specific condition. Herein, we describe a case of rectal metastasis from UC, treated with combined pembrolizumab and pelvic radiotherapy. CASE REPORT: A 67-year-old male patient with an invasive bladder tumour underwent robot-assisted radical cystectomy and ileal conduit diversion followed by neoadjuvant GC chemotherapy. The pathological findings showed high-grade UC, pT4a, with a negative surgical margin. He presented with an impacted ileus due to severe rectal stenosis on postoperative day 35 and underwent a colostomy. Pathologically, rectal biopsy confirmed rectal metastasis; thus, the patient was started on pembrolizumab 200 mg every 3 weeks and pelvic radiotherapy with a total dose of 45 Gy. The rectal metastases remained well controlled with stable disease status, and no adverse events were observed 10 months after the initiation of combined pembrolizumab and pelvic radiotherapy. CONCLUSION: Pembrolizumab combined with radiation therapy may be an alternative treatment for rectal metastases from UC.

Effectiveness of Retzius-Sparing Robot-Assisted Radical Prostatectomy in a Renal Transplant Recipient: a Case Report.

BACKGROUND: Prostate cancer (PCa) has increased as a long-term outcome of advanced immunosuppression in renal transplant recipients (RTRs). Retzius-sparing robot-assisted radical prostatectomy (Rs-RARP) is reportedly less time-consuming and has a higher continence recovery rate than the standard RARP without increasing the risk of complications. However, only a few cases of Rs-RARP in RTRs have been reported. CASE PRESENTATION: A 65-year-old man, who received a renal transplant 2 years prior, was diagnosed with low-risk PCa, per the D'Amico risk classification system, and underwent Rs-RARP with the da Vinci Xi robotic system. All port sites were placed contralateral to the allograft and compared with the standard RARP. The operative time was 187 min, and the estimated blood loss was 100 mL. The urethral catheter was removed on postoperative day 7 after confirming the absence of leakage using voiding cystourethrography. The patient was discharged on postoperative day 8. Pathologic findings showed localized PCa with a Gleason score of 3 + 3 and negative surgical margins. One year after the surgery, the patient had adequate urinary continence. His prostate-specific antigen level was <0.01 ng/mL, and his renal function was similar to that before surgery. CONCLUSIONS: We reported a case of PCa in an RTR, successfully treated via Rs-RARP, resulting in adequate continence without complications.

Comparison of Surgical Outcomes Between Enucleation and Standard Resection in Robot-Assisted Partial Nephrectomy for Completely Endophytic Renal Tumors Through a 1:1 Propensity Score-Matched Analysis.

Objective: Robot-assisted laparoscopic partial nephrectomy (RAPN) for completely endophytic renal tumors is challenging because of the tumor complexity. The enucleation technique is an ideal resection method to maximally preserve the renal parenchyma. In the present study, we investigated the surgical outcomes of RAPN for completely endophytic renal tumors and compared them between the enucleation and standard resection techniques. Methods: One hundred and forty-four patients who underwent RAPN for completely endophytic tumors were the subjects of this study. The subjects were divided into two groups according to the Surface-Intermediate-Base margin score (SIB score): the enucleation group (SIB score 0-2) and the standard resection group (SIB score 3-5). To minimize selection bias between the two surgical methods, patient variables such as age, sex, body mass index, American Society of Anesthesiologists score, tumor size, RENAL nephrometry score (RENAL NS), and preoperative renal function were adjusted using 1:1 propensity score matching. Results: Of the 144 patients, 72 were assigned to the enucleation group and 72 to the standard resection group. After matching, 45 patients were included in each group. The mean tumor size was 26-27 mm and the mean RENAL NS was 9.0-9.1, after matching. The enucleation group showed significantly better preservation of the estimated glomerular filtration rate in the early postoperative period (-4.9% vs -16%, p = 0.0005) and at 6-12 months after surgery (-4.9% vs -9.2%, p = 0.0327) than the standard resection group. In addition, a shorter operation time (140 vs 167 minutes, p = 0.0028) was observed in the enucleation group. Other outcomes, including estimated blood loss, positive surgical margin rate, incidence rate of complications, and length of hospital stay, were not significantly different between the two groups. Conclusion: The enucleation technique showed better surgical outcomes for completely endophytic renal tumors in terms of preservation of renal function and operation time than the standard resection technique.

Bilateral and multiple mixed epithelial and stromal tumors of the kidney: A case report.

Mixed epithelial and stromal tumor (MEST) of the kidney is a benign tumor occurring predominantly in older women. Histologically, MEST comprises tubuloglandular and cystic structures in an ovarian-like stroma. Bilateral and multiple cases are rare. We herein present a case of bilateral and multiple MEST in a 43-year-old woman. The patient presented with gross hematuria and was referred to a primary care physician. A computed tomography scan revealed 5 tumors in the right and 2 in the left kidney. Renal cell carcinoma was suspected, and left partial nephrectomy followed by right radical nephrectomy was planned. After the left partial nephrectomy, the histopathological diagnosis was MEST, which was consistent with the results obtained following needle biopsy. Therefore, the contralateral tumor was also suspected to be MEST, and needle biopsy was performed. The histopathological diagnosis was identical and the right kidney was spared. The patient is currently periodically monitored. As MEST is a benign tumor, preoperative diagnosis is crucial for avoiding overtreatment.