[Two Cases of Bleeding from the Ileal Conduit Due to Ectopic Varices].

Case 1 : A 75-year-old man was emergently admitted to our hospital with a complaint of continuous bleeding from the ileal conduit. The conduit was constructed by a total pelvic resection for sigmoid colon cancer that invaded the urinary bladder 24 years ago. Swollen cutaneous mucosa was seen around the ileal conduit, but no obvious bleeding spot was observed. The contrast-enhanced computed tomographic (CT) scan and 3D visualization revealed varices extending to the abdominal wall. Percutaneous transhepatic embolization successfully stopped the bleeding, but it was needed again after two years. Case 2 : A 72-yearold man with a history of open cystectomy and ileal conduit for bladder cancer came to our hospital two years after the surgery, complaining of continuous bleeding from the conduit. The skin around the stoma site was discolored purple, but no obvious bleeding site or bloody urine was observed. The CT scan similar to Case 1 revealed varices in the ileal conduit, and percutaneous transhepatic embolization successfully stopped the bleeding, but it was needed again after five months. After that, three months passed without recurrence.

Patient characteristics correlate with diagnostic performance of photodynamic diagnostic assisted transurethral resection of bladder tumors: A retrospective, single-center study.

BACKGROUND: Identification of patient subclasses that correlate with the diagnostic performance of photodynamic diagnostic (PDD)-assisted transurethral resection of bladder tumors (TURBT) may improve outcomes. METHODS: Data were extracted from patients that underwent PDD-assisted TURBT at the University of Tsukuba Hospital between 2018 and 2023. Sensitivity and specificity were evaluated based on PDD findings (excluding WL findings) and pathology results. Cluster analysis using uniform manifold approximation and projection and k-means methods was performed, focusing on patients with malignant lesions. RESULTS: A total of 267 patients and 2082 specimens were extracted. Sensitivity was lowest with regard to BCG treatment (53.7 %), followed by flat lesions (57.2 %), urine cytology class ≥ III (62.9 %), and recurrent tumors (64.5 %). In the cluster analysis of 231 patients with malignant lesions, two showed lower sensitivity: Cluster 3 (62.4 %), consisting of patients with recurrent tumors and post-BCG treatment, and Cluster 4 (55.7 %), consisting of patients with primary tumors and urine cytology class ≥ III. Clusters 1 and 2, consisting of patients without BCG treatment and patients with lower urine cytology classes, exhibited higher sensitivities (94.4 % and 87.7 %). Among all clusters, Cluster 4 had the highest proportion of specimens which were negative for both PDD and white light (WL) findings but actually had malignant lesions (20.8 %). CONCLUSIONS: PDD-assisted TURBT sensitivity was lower in subclasses after BCG treatment or with cytology class III or higher. Random biopsy for PDD/WL double-negative lesions may improve diagnostic accuracy in these subclasses.

Retroperitoneal sarcoma: a 10-year follow-up analysis using hospital-based cancer registry data in Japan.

OBJECTIVES: We sought clinical characteristics, survival outcomes, and prognostic factors for overall survival of retroperitoneal sarcoma in Japan. METHODS: A Japanese hospital-based cancer registry database with a pivotal 10-year follow-up was used to identify and enroll patients, registered from 106 institutions, diagnosed with retroperitoneal sarcoma in 2008-2009. Treating hospitals were divided by hospital care volume; high-volume hospitals and low-volume hospitals were defined as ≥ 4 and < 4 cases/year, respectively. RESULTS: A total of 91 men and 97 women were included, with a median age of 64 years. The most common histological type was liposarcoma in 101 patients, followed by leiomyosarcoma in 38 patients. The 5-year and 10-year overall survival rates were 44.1 and 28.3%. The majority of patients (n = 152, 80.9%) were treated at low-volume hospitals. High-volume hospital patients had higher 10-year overall survival rates than low-volume hospital patients (51.2% vs 23.2%, P = 0.026). Multivariate analysis revealed age over 60 years, treatment in low-volume hospitals and chemotherapy were independent predictors of unfavorable survival while treatment with surgery was an independent predictor of favorable survival. CONCLUSIONS: The possibility of surgical removal was suggested to be the most important prognostic factor for retroperitoneal sarcoma. Better survival was shown in patients treated at high-volume hospitals in our series.

The prognostic impact of treatment centralization in patients with testicular germ cell tumors: analysis of hospital-based cancer registry data in Japan.

BACKGROUND: To identify the prognostic impact of treatment centralization in patients with testicular germ cell tumors (TGCT). METHODS: We used a hospital-based cancer registry data in Japan to extract seminoma and non-seminoma cases that were diagnosed in 2013, histologically confirmed, and received the first course of treatment. To compare the 5-years overall survival (OS) rates of patients stratified by institutional care volume, we performed a Cox proportional hazards regression analysis using inverse probability of treatment weighting (IPTW) method to adjust patient backgrounds. RESULTS: A total of 1767 TGCT patients were identified. The 5-years OS rates for stage II and III TGCT patients treated at low-volume institutions (< 7 cases) were significantly worse than high-volume institutions (≥ 7 cases) (91.2% vs. 83.4%, p = 0.012). Histological stratification revealed that 5-year OS rates for stage II and III seminoma patients in the low-volume group were significantly worse than the high-volume group (93.5% vs. 84.5%, p = 0.041). Multivariate OS analysis using an IPTW-matched cohort showed that institutional care volume was an independent prognostic factor (hazard ratio 2.13 [95% confidence interval: 1.23-3.71], p = 0.0072). CONCLUSION: Our results indicate that stage II and III TGCT patients experience lower survival rates at low-volume institutions and would benefit from treatment centralization.

Comparison of perioperative outcomes and complications between intracorporeal, extracorporeal, and hybrid ileal conduit urinary diversion during robot-assisted radical cystectomy: a comparative propensity score-matched analysis from nationwide multi-institutional study in Japan.

BACKGROUND: To investigate the impact of different urinary diversion (UD) techniques on the peri- and postoperative complications of robot-assisted radical cystectomy (RARC) with ileal conduit. METHODS: We retrospectively analyzed 373 patients undergoing RARC with ileal conduit at 11 institutions in Japan between April 2018 and December 2021. Propensity score weighting was performed to adjust for confounding factors such as age, sex, body mass index, performance status, American Society of Anesthesiologists score, previous abdominal surgery, neoadjuvant chemotherapy, and preoperative high T stage (≥ cT3) and high N stage (≥ cN1). Perioperative complications were then compared among three groups: extracorporeal, intracorporeal, and hybrid urinary diversion (ECUD, ICUD, and HUD, respectively). RESULTS: A total of 150, 68, and 155 patients received ECUD, HUD, and ICUD, respectively. Bowel reconstruction time and UD time were significantly shorter in the ECUD group (p < 0.001), and console time was significantly longer and blood loss was significantly higher in the ICUD group (p < 0.001). For postoperative complications (Clavien-Dindo Classification grade ≥ 3), surgical site infection (p = 0.004), pelvic abscess (p = 0.013), anastomotic urine leak (p = 0.007), and pelvic organ prolapse (p = 0.011) significantly occurred in the ECUD group. For all grades, ileus was more common in the HUD group, whereas anastomotic stricture was more common in the ECUD group compared with the other groups (p < 0.05). CONCLUSIONS: Severe complications did not increase after HUD and ICUD compared with ECUD; however, console time tended to be longer and blood loss was slightly higher during RARC.

Variant allele frequency changes in TP53 predict pembrolizumab response in patients with metastatic urothelial carcinoma.

Prognoses for patients with metastatic urothelial carcinoma (mUC) have improved with pembrolizumab treatment, an immune checkpoint inhibitor, but clinical benefits are limited to a subset of patients. Therefore, a non-invasive biomarker to predict pembrolizumab response is required. The present study retrospectively examined genomic alterations in 25 plasma circulating tumor DNA (ctDNA) samples using targeted sequencing of 77 genes from 16 patients with mUC during pembrolizumab treatment. A total of 11 (68.8%) patients demonstrated ≥2 genomic alterations, including TP53 mutations (as defined by ctDNA-positive status). The proportion of responders to pembrolizumab in the ctDNA-positive group was higher compared with that in the ctDNA-negative group (72.7 vs. 20.0%). Furthermore, among all detected genomic alterations, variant allele frequency decreases in TP53 during pembrolizumab treatment were mainly associated with therapeutic response. Collectively, these data suggest that profiling of ctDNA in plasma, particularly TP53, may be useful for predicting and monitoring therapeutic responses to pembrolizumab in patients with mUC.

Complete Response to Enfortumab Vedotin in a Hemodialysis Patient with Metastatic Urothelial Carcinoma: A Case Report.

Enfortumab vedotin (EV) is an antibody-drug conjugate and a promising agent for metastatic urothelial carcinoma (mUC). However, evaluations in end-stage renal disease patients undergoing hemodialysis are unreported. Here, we report such a case. A 74-year-old woman with mUC, on hemodialysis for complete urinary tract extirpation, was diagnosed with multiple pulmonary metastases after treatment with gemcitabine-carboplatin followed by pembrolizumab. As third-line therapy, she received a standard dose of EV. She achieved complete response after 2 cycles without grade 3 or higher adverse events, demonstrating the utility of EV in this setting.

[Two Cases of Femoral Nerve Palsy after Pelvic Surgery].

Postoperative femoral nerve palsy (FNP) is a rare complication associated with urologic surgery. Inappropriate use of retractors, use of lithotomy position, and prolonged surgery that lead to the femoral nerve compression have been reported as risk factors for FNP. Here, we report two cases of FNP after pelvic surgery. Case 1: A 47-year-old woman underwent ureterocystoneostomy for a giant ureterocele. On the first postoperative day, she developed muscle weakness and paresthesia in the left lower leg. An orthopedic surgeon diagnosed her with FNP associated with the surgery. Case 2: An 82-year-old woman underwent radical cystectomy for invasive bladder cancer. On the second postoperative day, she developed extension deficit in the left lower leg and was diagnosed with an iatrogenic FNP. Although this complication is infrequent, at onset, it leads to difficulty in walking and gait disturbance in the patient. As a result, it greatly reduces the patient's postoperative quality of life. Therefore, preventive measures should be taken to reduce the risk of this postsurgical nerve injury, such as appropriate placement of retractors and proper patient positioning during the operation.

Prediction of early graft function after living donor kidney transplantation by quantifying the "nephron mass" using CT-volumetric software.

Early renal function after living-donor kidney transplantation (LDKT) depends on the "nephron mass" in the renal graft. In this study, as a possible donor-recipient size mismatch parameter that directly reflects the "nephron mass," the cortex to recipient weight ratio (CRWR) was calculated by CT-volumetric software, and its ability to predict early graft function was examined. One hundred patients who underwent LDKT were enrolled. Patients were classified into a developmental cohort (n = 79) and a validation cohort (n = 21). Using the developmental cohort, the correlation coefficients between size mismatch parameters, including CRWR, and the posttransplantation estimated glomerular filtration rate (eGFR) were calculated. Multiple regression analysis was conducted to define a formula to predict eGFR 1-month posttransplantation. Using the validation cohort, the validity of the formula was examined. The correlation coefficient was the highest for CRWR (1-month r = 0.66, p < 0.001). By multiple regression analysis, eGFR at 1-month was predicted using the linear model: 0.23 × donor preoperative eGFR + 17.03 × CRWR + 8.96 × preemptive transplantation + 5.10 (adjusted coefficient of determination = 0.54). In most patients in the validation cohort, the observed eGFR was within a 10 ml/min/1.73 m2 margin of the predicted eGFR. CRWR was the strongest parameter to predict early graft function. Predicting renal function using this formula could be useful in clinical application to select proper donors and to avoid unnecessary postoperative medical interventions.

Clinicopathological features of adrenal malignancies: Analysis of hospital-based cancer registry data in Japan.

OBJECTIVE: To identify the clinicopathological features of adrenal malignancies and analyze the prognoses of patients with adrenal cortical carcinoma (ACC) and malignant pheochromocytoma (MPCC). PATIENTS AND METHODS: We used a hospital-based cancer registry data in Japan to extract cases of adrenal malignancies that were histologically confirmed, diagnosed, and initially treated from 2012-2015. For survival analysis, we used data from the 2008-2009 cohort to estimate 5-year overall survival (OS) by the Kaplan-Meier method. RESULTS: A total of 989 adrenal malignancies were identified in the 2012-2015 cohort. The most common histologies were ACC (26.4%), diffuse large B-cell lymphoma (DLBCL; 25.4%), neuroblastoma (22.2%), and MPCC (11.9%). While most ACC and MPCC patients were in their 60s, DLBCL patients accounted for 61.5% of adrenal malignancies in the over-70 cohort. Among ACC patients with clinical staging data, 46.3% of patients were stage IV. Although surgery was a chief strategy for all stages, younger patients tended to receive combination therapy, including surgery and chemotherapy or hormone therapy. In the 2008-2009 cohort, the 5-year OS rates of ACC (n = 49) and MPCC (n = 23) patients were 56.2% and 86.4% while ACC patients without surgery had 1- and 2-year OS rates of 25.0% and 12.5%. CONCLUSION: In Japan, DLBCL accounted for the majority of adrenal malignancies in older patients. Despite advanced staging, ACC patients were mainly treated with surgery and their prognosis was not satisfactory. Such epidemiological data may be useful in considering initial management strategies.

[Adrenocortical Oncocytic Tumor : A Report of Two Cases].

Adrenocortical oncocytic tumors are rare. As the Weiss criteria overestimate the malignancy of oncocytic tumor due to histological hallmarks, the Lin-Weiss-Bisceglia system (LWB system) is required for an accurate diagnosis of the malignant potential of an oncocytic tumor. We report two cases diagnosed as an oncocytic tumor with uncertain malignant potential (borderline) and an oncocytic tumor (benign) based on the LWB system, both of which were diagnosed as malignant based on the Weiss criteria. Case 1 : A man in his 20s was referred to our hospital for treatment of a left adrenal tumor. A non-functional pheochromocytoma or adrenal cancer was suspected. He underwent surgical resection of the left adrenal tumor and left kidney. The specimen was positive for 3 of the 9 Weiss criteria, but met one minor criterion in the LWB system. He was diagnosed with an oncocytic tumor with uncertain malignant potential (borderline). Case 2 : A woman in her 40s was referred to our hospital for treatment of a left adrenal tumor. Under the possibility of adrenal cancer, she underwent surgical resection of the left adrenal tumor. The specimen was positive for 3 of the 9 Weiss criteria, but the specimen met no criteria in the LWB system. She was diagnosed with an oncocytic tumor (benign). There has been no recurrence of the oncocytic tumor as of 2 years of follow-up in the two patients.

Laparoendoscopic single-site surgery for urachal remnant with extraperitoneal approach through a suprapubic port.

INTRODUCTION: No standard procedure has been established for laparoendoscopic single-site surgery for urachal remnants (LESS-U). This study aimed to report the novel surgical techniques and initial outcomes of laparoendoscopic single-site surgery with an extraperitoneal approach through a suprapubic port for urachal remnants (spLESS). METHODS: Fifty-five patients (median age, 27 years; range, 15-69 years) who underwent LESS-U were analyzed. To overcome the limitations inherent in the conventional procedure (LESS-U through an umbilical port: uLESS), we modified the port placement and approached via the extraperitoneal space. spLESS is a novel procedure which reduces intestinal damage caused by the extraperitoneal approach and overcomes incomplete resection of the urachal remnant, especially in the bladder dome. Three trocars are inserted into the extraperitoneal space through a suprapubic port in spLESS, and complete resection of the urachal remnant from the umbilicus to the bladder is performed with an appropriate incision line. Patient characteristics and perioperative results were retrospectively collected. Cosmetic outcomes were prospectively evaluated using self-administered questionnaires (body image and photo-series questionnaire). RESULTS: spLESS and uLESS were performed in 43 and 12 patients, respectively. No differences were observed between the perioperative results. The cosmetic outcomes were compared between the groups using body image and photo-series questionnaires. No patient developed major complications; there was no recurrence in either group. CONCLUSIONS: spLESS is a novel procedure which can completely resect the urachal remnant and reduce the risk of intestinal damage. spLESS is a safe, effective, and feasible procedure with high postoperative cosmesis.

Granulocyte colony-stimulating factor associated arteritis in a patient with castration-resistant prostate cancer.

INTRODUCTION: Granulocyte colony-stimulating factor-associated arteritis is a rare adverse event of granulocyte colony-stimulating factor, with an incidence of 0.47% among all patients who receive granulocyte colony-stimulating factor. We herein present a case of granulocyte colony-stimulating factor-associated arteritis. CASE PRESENTATION: A 72-year-old man with castration-resistant prostate cancer and multiple bone metastases was treated with docetaxel and pegfilgrastim. He developed a high fever on day 12 without other symptoms. His white blood cell count and C-reactive protein levels were high. Antibiotic therapy was ineffective, and contrast-enhanced computed tomography showed thickened subclavian and brachiocephalic artery walls. He was diagnosed with granulocyte colony-stimulating factor-associated arteritis. CONCLUSION: When patients receiving chemotherapy with granulocyte colony-stimulating factor develop an unexplained fever, granulocyte colony-stimulating factor associated arteritis should be considered.

[False-Positive ¹²³I-Metaiodobenzylguanidine Scan in a Patient with Adrenocortical Cancer].

A 59-year-old woman presented with a left adrenal tumor 4 cm in diameter. The ¹²³I-metaiodobenzylguanidine (MIBG) scintigraphy showed apparent accumulation in the left adrenal tumor. However, the patient had no sign or symptoms suggesting pheochromocytoma. No biochemical evidence of catecholamine excess was noticed. Computed tomography (CT) revealed relatively strong enhancement in the arterial phase, which persisted until the portal phase. The computed tomography (CT) and magnetic resonance imaging showed 2 liver nodule suspected to be metastatic tumors. No ¹²³I-MIBG accumulation was seen in these nodules. CT also showed thyroid nodules with calcification, which suggested papillary thyroid cancer. Based on the findings, open left adrenalectomy, partial hepatectomy and segmentectomy were performed under the clinical diagnosis of pheochromocytoma and metastatic liver tumors. Histopathological diagnosis was adrenocortical cancer. There was only lymphocyte infiltration in the liver nodules. Postoperative recovery was uneventful, and the patient underwent partial thyroidectomy 6 months later. The pathological diagnosis was papillary thyroid cancer. She has been without recurrence or metastases for 18 months after adrenalectomy. We found only 6 cases of MIBG scintigraphy-positive adrenocortical cancer in the literature. The mechanisms for MIBG uptake in adrenocortical cancer are discussed with a review of the literature.

[A Case of Perfusion Failure of Peritoneal Dialysis Catheter Treated by Reduced Port Surgery].

A 17-year-old man received continuous ambulatory peritoneal dialysis (CAPD) catheter implantation and had started peritoneal dialysis. Perfusion failure of peritoneal dialysis catheter occurred one month after the catheter implantation. Transcatheter contrast examination revealed catheter obstruction about 4-5 cm from the catheter tip. We performed reduced port surgery to remove the obstruction. Laparoscopy revealed that the omentum was adhered to the abdominal wall and wrapped the catheter. We diagnosed the cause of catheter malfunction as omentum wrapping. We removed the omentum from the catheter, and repositioned the catheter into the Douglas fossa. Although CAPD worked successfully after the operation, perfusion failure recurred one month after the operation. The patient requested discontinuation of CAPD and change to hemodialysis. Therefore, we removed the CAPD catheter. The catheter was adhered to the omentum. Reduced port surgery for peritoneal dialysis catheter obstruction has the advantage of being minimally invasive and is a reliable procedure, but further studies are needed to reduce the recurrence rate of perfusion failure and to establish the procedure after perfusion failure.

PLD1 promotes tumor invasion by regulation of MMP-13 expression via NF-κB signaling in bladder cancer.

Invasion of bladder cancer (BC) cells from the mucosa into the muscle layer is canonical for BC progression while phospholipase D isoform 1 (PLD1) is known to mediate development of cancer through phosphatidic acid (PA) production. We therefore used in silico, in vitro and in vivo approaches to detail the effect of PLD1 on BC invasion. In BC patients, higher levels of PLD1 expression were associated with poor prognoses. PLD1 knockdown significantly suppressed cellular invasion by human BC cells and matrix metalloproteinase-13 (MMP-13) was observed to mediate this effect. In our mouse bladder carcinogenesis model, the development of invasive BCs was suppressed by PLD1 knockout and a global transcriptomic analysis in this model indicated MMP-13 as a potential tumor invasion gene with NF-κB (nuclear factor-kB) as its transcriptional regulator. Furthermore, PA administration increased MMP-13 expression in line with NF-κB p65 phosphorylation levels. Collectively, we demonstrate that PLD1 promotes tumor invasion of BC by regulation of MMP-13 expression through the NF-κB signaling pathway and that PLD1 might be a potential therapeutic target to prevent clinical progression in BC patients.

Retroperitoneal lymph node dissection for testicular cancer in a patient with a double inferior vena cava.

INTRODUCTION: A double inferior vena cava is a rare anomaly with an incidence ranging from 0.3% to 3.0%. In patients with a double inferior vena cava, it is important to understand the precise anatomy and possible irregular lymph node flow when performing surgery for malignancies. CASE PRESENTATION: A 60-year-old man with a non-seminoma was referred to our hospital after left high orchiectomy. Computed tomography revealed a double inferior vena cava and swollen masses in the para-aortic region. After four cycles of chemotherapy with etoposide and cisplatin, retroperitoneal lymph node dissection was safely performed with a modified template extended to the right side of the paracaval region by referring to three-dimensional images created by SYNAPSE VINCENT® software. CONCLUSION: Preoperative three-dimensional images were useful to understand this patient's unusual and complicated anatomical positions.

Case Report: Molecular Characterization of Aggressive Malignant Retroperitoneal Solitary Fibrous Tumor: A Case Study.

Solitary fibrous tumors (SFT) are mesenchymal neoplasms with a favorable prognosis usually originating from the visceral pleura. Rarely, they may occur at various extrapleural sites and show malignant behavior coupled with dedifferentiation. NAB2-STAT6 fusion gene and STAT6 nuclear expression are biomarkers for diagnosis of SFT in addition to CD34, Bcl-2, and CD99. Furthermore, several reports have shown specific NAB2-STAT6 fusion variants and loss of STAT6 protein expression are associated with malignancy. We report a rare case of retroperitoneal SFT which rapidly progressed to death within 35 days after admission. Autopsy found a primary tumor containing both benign and malignant histologies, with multiple metastatic sites similar to the malignant, dedifferentiated tumor. STAT6 was detected in the primary differentiated tumor but not in the primary dedifferentiated tumor or lung/liver metastases. However, the NAB2-STAT6 fusion gene (NAB2ex6/STAT6ex16 variant) was detected in the primary tumor and lung/liver metastases. Intriguingly, fusion gene expression at the transcriptional level was downregulated in the dedifferentiated tumors compared to the differentiated tumor. We further performed target DNA sequencing and found gene mutations in TP53, FLT3, and AR in the dedifferentiated tumors, with TP53 mutations especially found among them. We demonstrate that downregulation of NAB2-STAT6 fusion gene at the transcriptional level is associated with malignant SFT for the first time. Moreover, the present study supports the idea that TP53 mutations promote malignancy in SFTs.

[A Case of Retroperitoneal Bronchogenic Cyst Successfully Resected with Retroperitoneoscopic Surgery].

A 32-year-old woman was referred to our hospital for consultation with a suspected left adrenal tumor detected by ultrasonography at a health check. Computed tomography and magnetic resonance imaging revealed a 3×1×4 cm multilocular cystic mass arising from the diaphragmatic crura, suggesting a retroperitoneal bronchogenic cyst. The patient underwent excision of the cyst and adjacent diaphragm using a retroperitoneoscopic approach. Retroperitoneal bronchogenic cysts are rare. We review the cases of 26 patients who underwent laparoscopic resection of a retroperitoneal bronchogenic cyst.

Light-guided renal cyst fenestration during laparoscopic ureterocalicostomy in a patient with left ureteropelvic junction obstruction.

INTRODUCTION: Laparoscopic ureterocalicostomy is a useful alternative to laparoscopic pyeloplasty for treating ureteropelvic junction obstruction under certain conditions. One concern regarding this technique is the inevitability of amputation of the renal lower pole to expose the lower renal calyx. CASE PRESENTATION: A 43-year-old man who presented ureteropelvic junction obstruction and multiple renal cysts underwent laparoscopic pyeloplasty, which could not be performed because of the intrarenal ureteropelvic junction. We switched the surgical technique to modified laparoscopic ureterocalicostomy, wherein amputation of the lower renal pole was substituted with fenestration of a renal cyst under the guidance of ureteroscopic light. Computed tomography performed 2 months postoperatively showed good patency of the anastomosis. CONCLUSION: Light-guided laparoscopic renal cyst fenestration followed by ureterocalicostomy is feasible in patients with ureteropelvic junction obstruction and lower pole renal cysts adjacent to the lower renal calyx.