Urothelial Cell Carcinoma of the Renal Pelvis Misdiagnosed as Ureteropelvic Junction Obstruction: A Case Report.

Urothelial tumors are typically a disease affecting elderly individuals and are rare in young patients. Moreover, upper urinary tract urothelial carcinoma is extremely rare in the young age group. In this study, we present a case of urothelial cell carcinoma of the renal pelvis and ureter in a young man without risk factors of urothelial carcinoma, which was misdiagnosed as ureteropelvic junction obstruction and treated with a laparoscopic pyeloplasty.

Congenital Renal Arteriovenous Malformation: Diagnostic Clues and Methods.

Background and objectives: Renal arteriovenous malformation (AVM) is a rare disease and is difficult to be diagnosed by conventional methods because of its rarity. In this study, we investigated the diagnostic clues, and made an algorithm for the better diagnosis of renal AVM. Materials and Methods: We reviewed 13 patients who were diagnosed with AVM by using renal angiography from 1986 to 2020 at our institutes. We evaluated clinical features, diagnostic tools, treatment modalities, and outcomes after the treatment of patients. Results: All patients were female, and the mean age was 36.9 years (range 19 to 54 years). Twelve (92.3%) patients complained of gross hematuria. Four (30.8%) patients showed symptoms in relation with pregnancy and delivery. Angiographic findings demonstrated cirsoid type in 10 patients and aneurysmal type in 3 patients. Among the 11 patients who underwent computed tomography, AVMs were detected in 3 (27.3%) patients. Renal duplex Doppler was performed in 6 patients, and all of these patients were diagnosed with AVM, demonstrating a vascular turbulence or blood-rich area. Twelve patients were initially treated with transarterial embolization. Nephrectomy was performed in two patients due to persistent bleeding with hypovolemic shock. Conclusions: We should consider possible AVMs in patients who were not detected by conventional work up for hematuria, especially in mid-aged, pregnant, or recently delivered women. Renal duplex Doppler might be the optimal diagnostic modality in these patients. Our diagnostic algorithm could be aid to diagnosis and treatment for renal AVM patients.

Rapid Recurrence of Giant Multilocular Prostatic Cystadenoma after Laparoscopic Excision for Primary Case: A Case Report.

Giant multilocular prostatic cystadenoma is a rare benign tumor of the prostate gland that presents as a large retroperitoneal pelvic mass. The mass is usually located between the urinary bladder and rectum, and results in obstructive voiding symptoms and a change in bowel habits. Complete surgical excision is the treatment of choice. We present a case of rapid recurrent giant multilocular prostatic cystadenoma after laparoscopic excision for primary case. A previously healthy 54-year-old man presented with acute urinary retention. Prostate MRI showed a large cystic mass approximately 13 cm in size, multiple septa and lobulation in the prostate, and no visible solid lesions. Laparoscopic marsupialization of giant multilocular prostatic cystadenoma cysts was performed. One year later, the patient presented with local recurrence. Repeated laparoscopic complete resection was performed without any complications and further recurrence. Giant multilocular prostatic cystadenoma has the risk of recurrence in case of incomplete resection. Surgical treatment should be performed with the goal of complete removal following the same principles as cancer surgery.

Tubulocystic Renal Cell Carcinoma Is Not an Indolent Tumor: A Case Report of Recurrences in the Retroperitoneum and Contralateral Kidney.

Tubulocystic renal cell carcinoma (RCC) is a rare subtype of RCC that was recently included in the 2016 World Health Organization classification of tumors of the kidney. Most of these tumors exhibit indolent behavior with low metastatic potential. However, here we report a case of recurrent tubulocystic RCC with aggressive features in the retroperitoneum and contralateral kidney treated with targeted agents and radiofrequency ablation.

A Case of Incidental Schwannoma Mimicking Necrotic Metastatic Lymph Node from Bladder Cancer.

Background and Objectives: Retroperitoneal schwannoma is a very rare case of schwannoma which commonly occurs in the other part of the body. However, it is difficult to distinguish schwannoma from other tumors before pathological examination because they do not show specific characteristics on imaging study such as ultrasound, computed tomography (CT), and magnetic resonance image (MRI). Case summary: A 60-year-old male showed a retroperitoneal cystic tumor which is found incidentally during evaluation of coexisted bladder tumor. Neurogenic tumor was suspicious for the retroperitoneal tumor through pre-operative imaging study. Finally, a schwannoma was diagnosed by immunohistochemical examination after complete surgical excision laparoscopically. Conclusion: As imaging technology is developed, there may be more chances to differentiate schwannoma from other neoplasm. However, still surgical resection and histopathological examination is feasible for diagnosis of schwannoma.

A Case of Orbital Metastasis of Uterine Leiomyosarcoma With Intracranial Extension Presenting With Proptosis.

A 57-year-old woman presented with protrusion of the OS 2 months in duration and decreased vision 1 month in duration. The patient was diagnosed with uterine leiomyosarcoma approximately 3 years before presentation. Lung and liver metastases were diagnosed by biopsy 1 year prior to this visit. CT revealed a solid mass with central necrosis in the left lateral orbit that resulted in orbital shifting, bony destruction, and intracranial extension. The diagnosis was left orbital metastatic leiomyosarcoma, and the patient died 2 months after receiving the diagnosis.

Dihydrotestosterone enhances castration-resistant prostate cancer cell proliferation through STAT5 activation via glucocorticoid receptor pathway.

INTRODUCTION: We aimed to evaluate STAT5 expression and cell proliferation change after dihydrotestosterone (DHT) treatment in castration-resistant prostate cancer (CRPC) cells to elucidate the mechanism in relation to different androgen receptor (AR) expression status. METHODS: Using DU145, PC3, and LNCaP cells, cell viability assay and Western blot for phosphorylated STAT5 (p-STAT5) were done after DHT treatment at various concentrations. Endogenous levels of nuclear hormone receptor mRNA and protein were identified using real-time RT-PCR and Western blot. We treated the cells with RU486 and then glucocorticoid receptor (GR)-specific small interfering RNA (siRNA), to assess change in DHT-induced STAT5 activation. Immunofluorescence staining of DU145 cells with anti-GR and anti-pSTAT5 Ab before and after DHT treatment was done and visualized. RESULTS: DHT treatment enhanced STAT5 phosphorylation and promoted proliferation of all CRPC cells. Endogenous GR was identified strongly in DU145, weakly in PC3 but not in LNCaP cells. AR was identified strongly in LNCaP but not in DU145 cells. RU486 treatment abolished DHT-induced cell proliferation and STAT5 activation in both DU145 and PC3 cells but not in LNCaP cells. Similarly, GR-specific siRNA completely suppressed STAT5 activation. On immunofluorescence, activation of STAT5 and GR translocating into the nucleus after DHT treatment was confirmed. Immunoprecipitation confirmed direct complex formation between the GR and pSTAT5. CONCLUSION: In CRPC cells, DHT activated STAT5 enhancing cell proliferation. Activation was induced regardless of presence of AR and in cells devoid of AR, DHT used GR which formed direct complex with p-STAT5.

Sonographic findings of tuberculous vasitis.

The purpose of this series was to describe the sonographic findings of tuberculous vasitis. We conducted a retrospective analysis of 3 cases of tuberculous vasitis. The following grayscale and color Doppler sonographic features were analyzed: location, echogenicity of the lesion, epididymal or testicular involvement, presence of hydrocele, and blood flow within the lesion. All 3 patients had focal (n = 2) or multifocal (n = 1) involvement of the scrotal segment of the vas deferens. The sonographic findings for tuberculous vasitis were heterogeneously hypoechoic in all of the cases. On color Doppler sonography, no blood flow was identified within the lesions of the vas deferens. All 3 patients had tuberculous epididymitis in addition to tuberculous vasitis. Tuberculous vasitis presents with infection along with tuberculous epididymitis, and it appears as a heterogeneously hypoechoic lesion in the scrotal segment of the vas deferens adjacent to the epididymal tail.

A nationwide epidemiological study of testicular torsion in Korea.

Testicular torsion is a surgical emergency in the field of urology. Knowledge of the epidemiology and pathophysiology is significant to an urologist. However, the epidemiology of testicular torsion in Korea has not been studied. We performed a nationwide epidemiological study to improve knowledge of the epidemiology of testicular torsion. From 2006-2011, the Korean Urologic Association began the patient registry service. The annual number of patients with testicular torsion from 2006 to 2011 were 225, 250, 271, 277, 345, and 210, respectively. The overall incidence of testicular torsion in males was 1.1 per 100,000; However, the incidence in men less than 25 yr old was 2.9 per 100,000. Adolescents showed the highest incidence. Total testicular salvage rate was 75.7% in this survey. There was no geographic difference of testicular salvage rate. Minimizing the possibility of orchiectomy for testicular torsion is important to improve public awareness to expedite presentation and provider education to improve diagnosis and surgery.

An excitation wavelength-optimized, stable SERS biosensing nanoplatform for analyzing adenoviral and AstraZeneca COVID-19 vaccination efficacy status using tear samples of vaccinated individuals.

We introduce a label-free surface-enhanced Raman scattering (SERS) biosensing platform equipped with metallic nanostructures that can identify the efficacy of Oxford-AstraZeneca (AZD1222) vaccine in vaccinated individuals using non-invasive tear samples. We confirmed the hypothesis that the tears of people who receive the AZD1222 vaccine may be similar to those of adenovirus epidemic keratoconjunctivitis patients since the Oxford-AstraZeneca vaccine is derived from a replication-deficient ChAdOx1 vector of chimpanzee adenovirus. Additionally, we confirmed the potential of the three markers for estimating the vaccination status via analyzing the signals emanating from antibodies or immunoglobulin G by-product using our label-free, SERS biosensing technique with a high reproducibility (<3% relative standard deviation), femtomole-scale limit of detection (1 × 10-14 M), and high SERS response of >108. Therefore, our label-free SERS biosensing nanoplatforms with long-term storage and robust stability will enable rapid and robust monitoring of the vaccine presence in vaccinated individuals.

Massive retroperitoneal hematoma as an acute complication of retrograde intrarenal surgery: A case report.

BACKGROUND: Retrograde intrarenal surgery (RIRS) has been proven to be a safe and effective treatment modality in large-scale quantitative studies. However, although its safety profile has been established, it also has a potential risk of life-threatening complications. We here describe our experience with a patient who developed a huge periureteral hematoma after RIRS with holmium laser lithotripsy. CASE SUMMARY: A 73-year-old woman visited our center with a complaint of gross hematuria. An enhanced computed tomography (CT) scan revealed a 1.5-cm left renal pelvis stone with hydronephrosis. The patient underwent RIRS. During the surgery, a 12/14-Fr ureteral access sheath was applied and a 6-Fr ureteral catheter was indwelled thereafter. On postoperative day 1, she experienced aggravated left flank pain and left lower-quadrant tenderness without rebound tenderness. A follow-up CT scan was taken, which revealed a huge hematoma in the periureteral space, not in the perirenal space, with suspicious contrast medium extravasation. Immediate angiography was performed; however, it showed no evidence of active bleeding. She was conservatively managed with hydration and antibiotic and nonsteroidal anti-inflammatory drug therapy, and was discharged on postoperative day 7. However, she visited our outpatient department with recurrent left flank pain at 5 d from discharge. Ultrasonography confirmed that the double J-stent was intact. To rule out stent malfunction, the stent was changed. Decreased size of the hematoma was observed in the imaging studies, and conservative management for candiduria was performed for 1 wk. CONCLUSION: Although RIRS is an effective and safe procedure for the management of renal stones, clinicians should be aware of its potential complications.

Practice Pattern of Redo Varicocelectomy for Recurrent Varicocele according to Type of Initial Treatment: Retrospective Analysis of a United States-Based Insurance Claims Database.

PURPOSE: The objective of this study was to investigate the type of redo varicocelectomy according to the initial surgery type using a large population of USA insurance data. MATERIALS AND METHODS: This is a retrospective observational cohort study. Administrative claims data were extracted from the IBM® MarketScan Research Database. We included all newly diagnosed patients with varicocele from January 2007 to December 2014 using International Classification of Disease, 9th Revision, Clinical Modification (ICD-9-CM) codes. The treatment methods were identified by Current Procedural Terminology (CPT) code. RESULTS: A total of 261,785 subjects were diagnosed with varicocele. Of these, a total of 19,800 (7.6%) patients underwent varicocele surgery. Inguinal, abdominal, laparoscopic, microsurgery, and embolization surgery were performed in 66%, 19%, 10%, 3%, and 2%, respectively, as initial treatment. A total of 340 patients (1.7%) underwent redo varicocele surgery. Inguinal, microscopic, embolization, abdominal, and laparoscopic surgery were used as the redo method in 43%, 25%, 16%, 8%, and 7%, respectively. The redo inguinal approach was the preferred method in patients who first underwent inguinal, abdominal, and laparoscopic surgery, but not in patients who underwent microscopic or embolization procedures. Most patients who initially underwent microscopic varicocelectomy or embolization underwent redo varicocelectomy using the same method. CONCLUSIONS: Compared to the type of initial varicocelectomy, there were changes in the proportion of each type of surgical approach in redo operation procedures. While inguinal varicocelectomy is the most common method in redo operations, the number of microscopic varicocelectomy or embolization procedures is significantly increased in redo surgery.

Effect of the dual 5alpha-reductase inhibitor, dutasteride, on serum testosterone and body mass index in men with benign prostatic hyperplasia.

OBJECTIVE: To investigate the effects of dutasteride on serum testosterone level and body mass index (BMI) in men who received medical therapy for benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: In all, 120 patients with BPH were randomized to three treatment groups: tamsulosin 0.2 mg/day (alpha-blocker group), dutasteride 0.5 mg/day (dutasteride group), or tamsulosin 0.2 mg plus dutasteride 0.5 mg/day (combination group) for 1 year. For all patients the BMI and serum testosterone levels were checked at baseline and after 1 year of treatment. RESULTS: Among the evaluable 107 patients, the dutasteride (33) and combination groups (37) had significantly greater increases in serum testosterone level (16.3% and 15%, respectively) than the alpha-blocker group (37; 0.3%) after 1 year of treatment (both P < 0.001). When analysed by baseline serum testosterone tertile, the increases in serum testosterone level among the dutasteride and combination group were greatest in the lowest tertile. For BMI, the dutasteride and combination group had mean decreases of 0.17 and 0.20 kg/m(2), respectively, at 1 year, whereas the alpha-blocker group had a mean increase of 0.04 kg/m(2). The decreases in BMI for the dutasteride and combination group were statistically significant only in the lowest tertile (P = 0.048 and 0.010, respectively). CONCLUSION: Our results show that dutasteride treatment in men with BPH led to a significant increase in serum testosterone level and a significant decrease in BMI among those with relatively lower baseline serum testosterone levels.

Malignant renal cysts: diagnostic performance and strong predictors at MDCT.

BACKGROUND: Utilization of multidetector-row CT (MDCT) is anticipated to improve the diagnostic accuracy and reliability for determining malignant cysts. PURPOSE: To assess the diagnostic accuracy, interobserver agreement, benefit of consensus reading, and strong predictors of malignancy in determining malignant cystic renal masses at MDCT. MATERIAL AND METHODS: Two radiologists independently rated the probability of malignancy at MDCT in 72 benign and 53 malignant cysts. The accuracy and interobserver agreement for determining malignant cysts were evaluated. The strong predictors of malignancy were determined, and in patients with interobserver disagreement for determining malignant cysts, consensus readings were performed. RESULTS: Az value of the two readers was 0.905-0.936 and the sensitivity and specificity were 85-89% and 83-93%, respectively. The overall interobserver agreement for determining the malignant cyst was good as the kappa value was 0.696 (% agreement, 61% (76/125)). Thickened irregular wall, thickened irregular septa, and enhancing soft tissue component were strong predictors for malignancy with both readers. In the 17 patients with interobserver disagreement for determining malignant cysts, the sensitivity was improved from 38-63% to 89% by the consensus reading. CONCLUSION: At MDCT, some false negative decisions for determining malignant cysts can be corrected by consensus reading, and thickened irregular septa, thickened irregular wall, and enhancing soft tissue component are the strong predictors of malignant cysts.

Life-threatening complications associated with the tyrosine kinase inhibitor sunitinib malate.

Adverse events associated with sunitinib, such as cardiac toxicities, renal damage, and hemostatic complications, are well known. The authors report 3 cases in which patients experienced severe life-threatening complications after commencing sunitinib treatment. One patient developed heart failure with dilation of the left ventricle and decrease in the ejection fraction after one cycle of sunitinib and required treatment with an angiotensin-converting enzyme inhibitor, loop diuretics, and dobutamine. Another patient developed coronary artery stenosis after one cycle of sunitinib and was managed through percutaneous coronary intervention. Although follow-on coronary angiography revealed normal findings after 6 further cycles of sunitinib, this patient eventually expired due to multi-organ failure. The third patient had chronic renal failure before sunitinib treatment and required hemodialysis due to acute-on-chronic renal failure after commencing sunitinib treatment.

Urinary Stone Disease in Pregnancy: Current Management Practices in a Large National Cohort.

OBJECTIVE: To define current national practice patterns of imaging modalities and urologic procedures in pregnant women with urinary stone disease. METHODS: Using the IBM MarketScan national insurance claims database, we identified pregnant women with urinary stone disease and their corresponding gestational age between 2011 and 2016 using administrative claims data. We then assessed each encounter for urinary stone disease or stone-related urologic procedure during their pregnancy. We abstracted demographic information as well as codes for stone procedures and imaging. RESULTS: We identified 14,298 pregnant women with urinary stone disease during the study period. Of the 12,315 undergoing abdominal imaging (86.1%), magnetic resonance imaging was used in 2.8%, x-ray in 9%, and ultrasound in 74.3%. Computed tomography was not used as a diagnostic modality during pregnancy. Procedural intervention was performed in 749 women (5.2%): 476 (3.3%) ureteral stent placement without definitive stone treatment, 93 (0.6%) percutaneous nephrostomy placement, and 180 (1.3%) ureteroscopy (URS) for definitive stone treatment. URS was most commonly performed before 34 weeks gestation with only 27 cases (15%) performed after. CONCLUSION: This large national cohort reveals the current imaging and procedural practice patterns for urinary stone disease during pregnancy and provides a critical baseline as these practice patterns evolve in the future.

Differential diagnosis of complex cystic renal mass using multiphase computerized tomography.

PURPOSE: We evaluated the additional usefulness of multiphase computerized tomography for improving the differential diagnosis of cystic renal masses by the Bosniak classification. MATERIALS AND METHODS: We reviewed the records of 104 patients with Bosniak class II (29 or 27.8%), III (38 or 36.5%) and IV (37 or 35.7%) cystic renal masses managed surgically between 1997 and 2007. On preoperative multiphase computerized tomography enhancement differences in HU between the precontrast and corticomedullary phases were measured at the highest enhancement area to correlate with pathological findings. RESULTS: Renal cell carcinoma was diagnosed in 56 patients (53.8%). Of the tumors 35 (62.5%) showed clear cell histology. According to Bosniak class 3 (11.5%), 21 (55.2%) and 32 (86.4%) class II to IV lesions, respectively, were diagnosed as renal cell carcinoma. For renal cell carcinoma and benign cysts mean HU at the precontrast phase was similar (31.5 and 32.4 HU, respectively), while renal cell carcinoma showed a significantly higher measurement at the corticomedullary phase (112.9 vs 59.8 HU, p <0.0001). To differentiate renal cell carcinoma a corticomedullary phase minus precontrast phase value of greater than 42 HU was predictive with 97.1% sensitivity and 85.7% specificity (area under the ROC curve 0.966). In a multiple regression model the corticomedullary phase minus precontrast phase value and the Bosniak classification independently determined malignant pathological findings (corticomedullary phase minus precontrast phase greater than 42 HU HR 31.541, 95% CI 8.320-119.563 and Bosniak class HR 5.545, 95% CI 2.153-14.279, each p <0.0001). CONCLUSIONS: In cases of complex cystic renal masses diagnostic accuracy can be improved to differentiate renal cell carcinoma by combining Bosniak class and enhancement differences measured on multiphase computerized tomography between precontrast and maximal enhancement phases. This would help determine the need for and the method of surgical treatment.

Change of Trends in the Treatment Modality for Pediatric Nephrolithiasis: Retrospective Analysis of a US-Based Insurance Claims Database.

Purpose: The objective of this study was to show the prevalence and investigate treatment trends of pediatric nephrolithiasis based on a large population of U.S. insurance individual's data. Materials and Methods: This research involved a retrospective observational cohort study. Administrative claims data were extracted from the IBM® MarketScan® Research Database. We included all patients newly diagnosed with nephrolithiasis, aged <18 years old at the time of diagnosis from January 1, 2007, to December 31, 2014. The patient cohort with nephrolithiasis was selected using the International Classification of Disease, 9th Revision, Clinical Modification (ICD-9-CM) code for nephrolithiasis. Each treatment method was searched by Current Procedural Terminology (CPT) code. Results: A total of 28,014 patients were found to have nephrolithiasis in our cohort. Of nephrolithiasis patients, 701 (2.5%) patients were treated by surgical methods. The mean age of patients at the time of treatment was 13 years old. Extracorporeal shockwave lithotripsy (SWL) was the most used treatment modality during the period. SWL was performed in 66% of patients. The number of cases of SWL did not tend to change according to year, whereas retrograde intrarenal surgery (RIRS) tended to increase from 15% to 31%. Percutaneous nephrolithotripsy (PCNL) decreased from 13% to <10 cases. The number of open surgeries was very small and did not show any tendency. Conclusion: During the study period, SWL is stable. RIRS has become more popular in treating renal stones, whereas PCNL has decreased. These results suggest that the RIRS has become more popular than PCNL in treating large renal stones.

Changing Trends in the Treatment of Nephrolithiasis in the Real World.

INTRODUCTION: Changes in the surgical treatment of nephrolithiasis, owing to recent technical advances and innovations, have made treatments more effective and less invasive. In this retrospective, observational cohort study, we identified the changing trends in the treatment of nephrolithiasis. MATERIALS AND METHODS: We included patients with newly diagnosed nephrolithiasis who received any treatment in the United States, including extracorporeal shockwave lithotripsy (SWL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL), and open surgery, from January 2007 to December 2014. Demographic factors, such as age, sex, region, surgical treatment type, and cost data, were analyzed. RESULTS: The median age of patients at treatment was 52 years, and the ratio of men and women was similar. There were definite changes in the trends of all treatment modalities (p < 0.01). Both the number and percentage tended to increase for RIRS, whereas for SWL, the number increased, but the percentage showed a steady decrease. In PCNL, both number and percentage increased to a minor degree. The overall cost of nephrolithiasis treatments during the study period nearly doubled (from $30,998,726 to $57,310,956). The number of treatments and average cost per treatment increased annually for each treatment modality. RIRS was the least expensive; the other procedures in decreasing order of their mean costs were as follows: SWL, PCNL, and open surgery. CONCLUSIONS: There was a gradual but constant change in treatment trends of nephrolithiasis, with an increasing trend for RIRS and a decreasing trend for SWL. Although PCNL has relatively invasive characteristics, it is still in steady demand.

Conversion to monotherapy with luteinizing-hormone releasing hormone agonist or orchiectomy after reaching PSA nadir following maximal androgen blockade is able to prolong progression-free survival in patients with metastatic prostate cancer: A propensity score matching analysis.

The present study evaluated androgen deprivation methods to determine the approach that most improves the progression-free survival (PFS) of patients with metastatic prostate cancer. Patients had received continuous maximal androgen blockade (MAB) or monotherapy [luteinizing-hormone releasing hormone (LHRH) agonist or orchiectomy] following the reaching of the prostate specific antigen (PSA) nadir. The medical records of 293 patients who received MAB following a diagnosis of metastatic prostate cancer were retrospectively reviewed. Following attainment of the PSA nadir and treatment with MAB, patients were maintained on continuous MAB (group CMAB) or converted to monotherapy (group MONO). Disease progression, defined as progression to castration-resistant prostate cancer, was evaluated and compared between the treatment modalities. PFS was compared between patients who received CMAB vs. MONO using 2:1 (102:53) propensity score matching; the basic clinicopathological characteristics (age, Gleason score, PSA and extent of bone metastasis) were similar between the groups. Disease progression was observed in 70.9% of all patients, with a median treatment period of 22.7 months. The median PFS time was 19.5 months in the CMAB group and 28.8 months in the MONO group (P=0.008). Kaplan-Meier analysis demonstrated that PFS was significantly associated with the type of maintenance androgen deprivation therapy (ADT; log rank <0.005). Multivariate analysis revealed that the type of maintenance ADT and the pretreatment extent of bone metastasis were independent predictors of prolonged PFS. In this propensity score matched-analysis, conversion to monotherapy with a LHRH agonist or orchiectomy following attainment of the PSA nadir with initial MAB, prolonged the PFS, suggesting that monotherapy maintenance following initial MAB may benefit patients by reducing side effects without decreasing treatment efficacy.