C-reactive Protein Is a Prognostic Factor for Survival in Metastatic Upper Tract Urothelial Carcinoma Patients Receiving Pembrolizumab.

BACKGROUND/AIM: The number of available treatment options for urothelial carcinoma has increased recently. Upper tract urothelial carcinoma (UTUC) is relatively rare compared with bladder cancer. There are few reports on the efficacy of immune checkpoint inhibitors (ICIs) for metastatic UTUC, and ICIs may occasionally show less efficacy and cause severe side effects. Therefore, it is important to predict the treatment response and change the treatment strategy as appropriate. We investigated the prognostic factors for treatment response in patients with metastatic UTUC treated with pembrolizumab at our hospital. PATIENTS AND METHODS: Patients who received pembrolizumab for UTUC between January 2018 and June 2023 were analyzed. Patients who presented with bladder cancer complications at initial diagnosis were excluded. The primary endpoints assessed were overall survival (OS) and progression-free survival (PFS). Statistical analyses were conducted using laboratory values obtained before and after pembrolizumab administration. The relationship between cancer and inflammation is important. Therefore, we analyzed this relationship using prognostic factors for urothelial carcinoma as previously reported. Specifically, pretreatment C-reactive protein (CRP) level, neutrophil-to-lymphocyte ratio (NLR), and NLR/albumin values were examined. RESULTS: Forty-seven patients were analyzed. The median PFS was 66 days (24-107 days), and the median OS was 164 days (13-314 days). A CRP level <1 before the first cycle was a useful factor in the multivariate analysis for both OS and PFS [OS: p=0.004, hazard ratio (HR)=3.244, 95% confidence interval (CI)=1.464-7.104; PFS: p=0.003, HR=2.998, 95%CI=1.444-6.225]. CONCLUSION: CRP level is a prognostic factor for pembrolizumab treatment response in patients with UTUC.

MMP1, IL-1ß, sTNFR-1, and IL-6 are prognostic factors for patients with unresectable or metastatic renal cell carcinoma treated with immune checkpoint inhibitors.

BACKGROUND: Few studies have reported reliable prognostic factors for immune checkpoint inhibitors (ICIs) in renal cell carcinoma (RCC). Therefore, we investigated prognostic factors in patients treated with ICIs for unresectable or metastatic RCC. METHODS: We included 43 patients who received ICI treatment for RCC between January 2018 and October 2021. Blood samples were drawn before treatment, and 73 soluble factors in the plasma were analyzed using a bead-based multiplex assay. We examined factors associated with progression-free survival (PFS), overall survival (OS), and immune-related adverse events (irAE) using the Chi-squared test, Kaplan-Meier method, and the COX proportional hazards model. RESULTS: Patients exhibited a median PFS and OS of 212 and 783 days, respectively. Significant differences in both PFS and OS were observed for MMP1 (PFS, p < 0.001; OS, p = 0.003), IL-1ß (PFS, p = 0.021; OS, p = 0.008), sTNFR-1 (PFS, p = 0.017; OS, p = 0.005), and IL-6 (PFS, p = 0.004; OS, p < 0.001). Multivariate analysis revealed significant differences in PFS for MMP1 (hazard ratio [HR] 5.305, 95% confidence interval [CI], 1.648-17.082; p = 0.005) and OS for IL-6 (HR 23.876, 95% CI, 3.426-166.386; p = 0.001). Moreover, 26 patients experienced irAE, leading to ICI discontinuation or withdrawal. MMP1 was significantly associated with irAE (p = 0.039). CONCLUSION: MMP1 may be associated with severe irAE, and MMP1, IL-1ß, sTNFR-1, and IL-6 could serve as prognostic factors in unresectable or metastatic RCC treated with ICIs. MMP1 and IL-6 were independent predictors of PFS and OS, respectively. Thus, inhibiting these soluble factors may be promising for enhancing antitumor responses in patients with RCC treated with ICIs.

Screening for prostate cancer in a city in Japan: age-specific prostate-specific antigen cutoff thresholds.

PURPOSE: Older men have higher prostate-specific antigen levels than younger men. However, the current Japanese Urological Association guidelines recommend secondary screening at a cutoff value of 4.0 ng/mL, even in older men. Here, we reexamined the cutoffs for older men using a prostate screening cohort in Japan and first performed an analysis to determine the indication cutoffs for detecting positive biopsies. METHODS: Data from 68,566 prostate cancer screenings in the city in 2018 were combined with cancer registration data. The optimal prostate-specific antigen levels to predict prostate cancer in different age groups were calculated using receiver operating characteristic curves after determining whether a cancer was registered within one year of screening. RESULTS: At the conventional prostate-specific antigen threshold of 4.0 ng/mL, the sensitivity, specificity, and negative predictive value were 94.9%, 91.7%, and 91.7%, respectively. The optimal prostate-specific antigen cutoff values for patients aged 50-59 years, 60-69 years, 70-79 years, and over 80 years were 3.900 ng/mL, 4.014 ng/mL, 4.080 ng/mL, and 4.780 ng/mL, respectively. CONCLUSIONS: The sensitivity and specificity of prostate cancer screening in the city were high, indicating a highly accurate screening. The prostate-specific antigen threshold was 4.78 ng/mL in patients older than 80 years. A higher prostate-specific antigen threshold may be useful in men over 80 years of age to avoid excess biopsy and reduce costs. Our results suggest that the current Japanese method of using PSA 4.0 ng/mL as a cutoff regardless of age may not be preferable for older men.

Review of the Developing Landscape of Prostate Biopsy and Its Roles in Prostate Cancer Diagnosis and Treatment.

Prostate cancer remains a significant global health challenge. Traditionally anchored by the Gleason score/Grade Group (GS/GG), the landscape of prostate cancer diagnosis is undergoing transformative steps, particularly in the domain of biopsy procedures. GS/GG continues to be pivotal in malignancy grading, but recent technological strides have augmented the diagnostic relevance of biopsies. Integral to this progression is the adoption of advanced imaging techniques, especially magnetic resonance imaging, which has refined biopsy accuracy and efficiency. A deep understanding of prostate cancer pathology reveals a cribriform pattern and intraductal carcinoma of the prostate as independent forms of malignancy, suggesting a potentially aggressive disease course. Furthermore, the distinct behaviour of ductal adenocarcinoma and small cell carcinoma of the prostate, compared with acinar adenocarcinoma, necessitates their accurate differentiation during biopsy. The genomic era ushers in a renewed emphasis on tissue samples obtained from prostate biopsies, especially as mutations in genes, such as BRCA1/2, and paves the way for precision medicine. This review encapsulates the evolving dynamics of prostate biopsy, from technological advancements to the profound implications on prostate cancer management and therapy.

Review of the Developing Landscape of Prostate Biopsyand Its Roles in Prostate Cancer Diagnosis andTreatment

Prostate cancer remains a significant global health challenge. Traditionally anchored by the Gleason score/Grade Group (GS/GG), the landscape of prostate cancer diagnosis is undergoing transformative steps, particularly in the domain of biopsy procedures. GS/GG continues to be pivotal in malignancy grading, but recent technological strides have augmented the diagnostic relevance of biopsies. Integral to this progression is the adoption of advanced imaging techniques, especially magnetic resonance imaging, which has refined biopsy accuracy and efficiency. A deep understanding of prostate cancer pathology reveals a cribriform pattern and intraductal carcinoma of the prostate as independent forms of malignancy, suggesting a potentially aggressive disease course. Furthermore, the distinct behaviour of ductal adenocarcinoma and small cell carcinoma of the prostate, compared with acinar adenocarcinoma, necessitates their accurate differentiation during biopsy. The genomic era ushers in a renewed emphasis on tissue samples obtained from prostate biopsies, especially as mutations in genes, such as BRCA1/2, and paves the way for precision medicine. This review encapsulates the evolving dynamics of prostate biopsy, from technological advancements to the profound implications on prostate cancer management and therapy (AU)

Use of Sotrovimab for COVID-19 in a Patient with International Germ Cell Consensus Classification Poor Prognosis Testicular Germ Cell Tumor.

A 35-year-old man was diagnosed with stage IIIC non-seminoma with paralysis of the lower half of his body due to 8th thoracic spine metastasis. The patient received bleomycin, etoposide, and cisplatin (BEP) therapy. On day 4 of the second course of BEP, the patient developed a fever and was diagnosed with coronavirus disease (COVID-19). COVID-19 was suspected to worsen because of cancer and chemotherapy-induced immunosuppression. However, the benefits of continuing BEP therapy outweighed these risks. After obtaining fully informed consent, BEP therapy was continued from day 5, while sotrovimab (anti-COVID-19 drug) was administered. The second course of BEP was completed without worsening severe COVID-19 or bleomycin-induced lung injury. The patient completed four courses of BEP, with normalization of tumor markers, partial response on imaging, and improvement in lower body paralysis. In this case, we successfully treated a patient with testicular germ cell tumor with chemotherapy while having COVID-19 without treatment delay. During the COVID-19 pandemic, concomitant chemotherapy and COVID-19 treatment are warranted because delaying treatment will decrease the efficacy of highly curative diseases such as germ cell tumors.

Localized amyloidosis of the ureter: a case report.

BACKGROUND: Amyloidosis is a collection of disorders characterized by the extracellular deposition of amyloid, a specialized fibrous protein, in diverse tissues, leading to functional impairments. CASE PRESENTATION: A 70-year old Asian-Japanese female was referred to our department for further examination of her left hydronephrosis come from lower ureteral obstruction. Contrast enhanced CT and retrograde pyelo-nephrography revealed left ureteral tumor. Though ureteroscropic biopsy did not show malignant pathological findings, ureteroscopic image suspected malignant disease, thus nephroureterectomy was performed. Pathological findings revealed localized ureteral amyloidosis. Whole body examination including gastro endoscopy and cardio ultrasonography could not reveal amyloidosis except ureter. She was free from recurrence 9 months postoperatively. CONCLUSION: We herein report a rare case of localized ureteral amyloidosis.

Chronological Change in EPHA2 Protein Expression Is Associated With Recurrence of Bladder Cancer.

BACKGROUND/AIM: Bladder cancer is the most common urinary tract cancer. Patients diagnosed with advanced T-stage/muscle-invasive bladder cancer through transurethral resection of bladder tumors (TURBT) are treated with total radical cystectomy; however, there is a high chance of recurrence. Nevertheless, markers for predicting this recurrence are not currently available. Here, we evaluated the chronological change of ephrin type-A receptor 2 (EPHA2) expression, a molecule known for its role in cell adhesion, to predict bladder cancer recurrence after cystectomy, using TURBT and cystectomy specimens. MATERIALS AND METHODS: An immunostaining evaluation method that combines whole-slide images and image analysis software was developed to quantify and evaluate stainability objectively. We assessed the correlation between EPHA2 expression and bladder cancer recurrence using this novel immunostaining method and chronological changes in target protein expression in TURBT and radical cystectomy samples. RESULTS: In TURBT specimens, the number of cases with a high N-terminal/C-terminal EPHA2 ratio in the group with recurrence was significantly higher than in the non-recurrent group (p=0.019). The number of cases with a high level of C-terminal EPHA2 positivity in the radical cystectomy specimen when compared to the TURBT specimen obtained from the same patient was significantly higher in the recurrent group than in the non-recurrent group (p=0.0034). CONCLUSION: EPHA2 appears to be a promising marker for bladder tumor recurrence after cystectomy and its evaluation may enable the selection of appropriate cases for adjuvant therapy among patients undergoing radical cystectomy. Further studies, including mass-scale analysis, are required to confirm these results.

Significance of non-standardized magnetic resonance imaging abnormalities and subsequent targeted prostate cancer biopsy for pathologists: A retrospective observational study.

Prostate biopsy is essential in diagnosing prostate cancer. The Prostate Imaging-Reporting and Data System (PI-RADS) and magnetic resonance imaging (MRI)-transrectal ultrasound fusion-guided biopsy are also useful for diagnosis. However, the burden of implementing and maintaining these techniques should be considered. Therefore, we investigated the significance of non-standardized pre-biopsy MRI abnormalities (conditions not in accordance with PI-RADS) and subsequent targeted biopsy. We collected clinicopathological data, including the presence or absence of MRI abnormalities, through biopsies from January 2017 to February 2022 at the Kanagawa Cancer Center and performed statistical analyses. We enrolled in 1086 cases: MRI abnormalities were observed in 861 cases (79.3%). In these 861 cases, the adenocarcinoma detection rate, number of positive cores, and length of the highest Grade Group (GG) lesions were significantly higher. In the multivariate analysis, MRI abnormalities were the most significant factor for detecting adenocarcinoma of ≥GG 2 (odds ratio: 4.52, 95% confidence interval: 3.08-6.63). Targeted biopsy showed a higher percentage of positive cores with ≥GG2 and longer highest GG lesion lengths than systematic biopsy. Furthermore, the highest GG was upgraded in 109 of 788 cases by targeted biopsy. However, several adenocarcinomas (125/788; 15.9%) could not be detected using only targeted biopsy. Non-standardized MRI abnormalities are powerful predictors of cancer and grading. Targeted biopsies based on MRI abnormalities provide several benefits. Owing to the relatively low implementation hurdle, these biopsies may serve as a bridge until the ideal approaches are popularized if the limitations are well understood.

[A CASE OF RENAL CELL CARCINOMA WITH SMALL INTESTINE METASTASIS DURING NIVOLUMAB PLUS IPILIMUMAB].

A 71-year-old man with a history of hoarseness and right upper extremity numbness was referred to our department for evaluation of an intrathoracic mass that was detected on chest radiography and a right kidney tumor observed on computed tomography (CT). Histopathological examination of percutaneous kidney biopsy and bronchoscopic lung biopsy specimens revealed renal clear cell carcinoma with multiple lung metastases. The patient showed a poor risk based on the International Metastatic renal cell carcinoma Database Consortium score, and nivolumab plus ipilimumab were initiated as first-line therapy. His symptoms gradually improved, following four courses of nivolumab plus ipilimumab treatment, and CT revealed shrinkage of all lesions. However, he developed diarrhea, rash, anemia, and elevated serum C-reactive protein levels (CRP) following this therapy. Diarrhea and rash were considered immune-related adverse events, and he was treated with oral prednisolone and topical corticosteroid. Nivolumab administration was discontinued because anemia worsened together with elevated serum CRP levels despite improvement in diarrhea. He subsequently developed constipation and abdominal bloating, following further treatment for 4 months. CT revealed intestinal tumor-induced intussusception, necessitating partial resection of the small intestinal tumor, which was histopathologically diagnosed as metastases. Both anemia and elevated CRP improved postoperatively. Currently, all metastatic lesions other than the resected intestine have continued to respond to treatment over 12 months after initiation of nivolumab plus ipilimumab therapy.

Prognosis of patients with T1 bladder cancer after en bloc transurethral resection of bladder tumor stratified by invasion to the level of the muscularis mucosa.

PURPOSE: To evaluate the prognosis of patients with pT1 bladder cancer who underwent en bloc resection of bladder tumors (ERBTs), stratified by invasion to the muscularis mucosa (MM) level. METHODS: Among 64 specimens obtained by ERBT with bipolar energy from patients with pT1 bladder cancer, MM was detected in 61 specimens. Thus, 61 specimens were included in this retrospective study. Patients were stratified by invasion to the MM level (pT1a, invasion above the MM level; pT1b, invasion within the MM level; and pT1c, invasion beyond the MM level). In specimens with discontinuous MM, invasion to the MM level was predicted from the dispersed MM in the specimen. The primary endpoints were progression-free survival (PFS) and cancer-specific survival (CSS). RESULTS: Progression occurred in 2/39 patients with pT1a (5.1%), 1/6 patients with pT1b (16.7%), and 6/16 patients with pT1c cancer (37.5%). Cancer death occurred in 1/39 patients with pT1a (2.6%), 0/7 patients with pT1b, and 3/16 patients with pT1c cancer (18.8%). Patients with pT1a or pT1b cancer had a significantly better prognosis than those with pT1c cancer. On univariate analysis, tumor size ≥ 3 cm and pT1c were significantly associated with shorter PFS. On multivariate analysis, only pT1c was independently associated with shorter PFS. CONCLUSION: This is the first study evaluating the prognosis by T1 substaging based on invasion to the MM level using ERBT specimens. ERBT provided high-quality specimens for diagnosing the MM and showed poor prognosis in pT1c bladder cancer. ERBT could be an appropriate surgical approach for an accurate diagnosis and prognosis of the T1 bladder cancer substage.

Pembrolizumab-Induced Severe Neuropathy in a Patient with Metastatic Urothelial Carcinoma after Achieving Complete Response: Guillain-Barré Syndrome-Like Onset.

An 85-year-old female was admitted to our hospital for left ureteral cancer and para-aortic lymph node metastasis. To control hematuria, a laparoscopic retroperitoneal nephroureterectomy was performed, and papillary urothelial carcinoma (pT3b) was found. To treat para-aortic lymph node metastasis, she received chemotherapy with gemcitabine and nedaplatin. After 2 cycles, a computed tomography scan revealed its disappearance; however, bilateral lung metastases appeared. The patient was administered second-line therapy with pembrolizumab every 3 weeks. After 3 courses, lung metastases disappeared and she achieved a complete response. After the fifth administration of pembrolizumab, she was readmitted with right upper limb pain and weakness in both lower extremities. She was diagnosed with pembrolizumab-induced grade 3 peripheral neuropathy with Guillain-Barré syndrome-like onset. High-dose monocorticotherapy was initiated for treatment. Three weeks later, the pain and weakness of the limbs improved. After discharge, the dose of prednisolone was tapered and there was no relapse of adverse events. Pembrolizumab was discontinued at the onset of neuropathy, but she maintained a complete response.

[A Case of Solitary Metastasis of Renal Cell Carcinoma to the Thyroid Gland].

A case of solitary metastasis of renal cell carcinoma to the thyroid gland is presented. The patient was a 82-year-old man found to have an abnormal mass in his neck. He had a past history of renal clear cell carcinoma of the left kidney (pT1aN0M0, G1>2, alveolar type, clear cell subtype), which had been resected 12 years previously. Ultrasonography revealed a tumor mass in the right hemithyroid gland. This time fine needle biopsy of the thyroid tumor suggested metastatic thyroid carcinoma. Right hemithyroidectomy was performed last year. The histopathological findings were suggestive of clear cell carcinoma, thus metastatic renal carcinoma was diagnosed. This is the 26th case of thyroid solitary metastasis of clear cell renal cell carcinoma reported in Japan to date.

Developing a preoperative predictive model for ureteral length for ureteral stent insertion.

BACKGROUND: Ureteral stenting has been a fundamental part of various urological procedures. Selecting a ureteral stent of optimal length is important for decreasing the incidence of stent migration and complications. The aim of the present study was to develop and internally validate a model for predicting the ureteral length for ureteral stent insertion. METHODS: This study included a total of 127 patients whose ureters had previously been assessed by both intravenous urography (IVU) and CT scan. The actual ureteral length was determined by direct measurement using a 5-Fr ureteral catheter. Multiple linear regression analysis with backward selection was used to model the relationship between the factors analyzed and actual ureteral length. Bootstrapping was used to internally validate the predictive model. RESULTS: Patients all of whom had stone disease included 76 men (59.8%) and 51 women (40.2%), with the median and mean (± SD) ages of 60 and 58.7 (±14.2) years. In these patients, 53 (41.7%) right and 74 (58.3%) left ureters were analyzed. The median and mean (± SD) actual ureteral lengths were 24.0 and 23.3 (±2.0) cm, respectively. Using the bootstrap methods for internal validation, the correlation coefficient (R2) was 0.57 ± 0.07. CONCLUSION: We have developed a predictive model, for the first time, which predicts ureteral length using the following five preoperative characteristics: age, side, sex, IVU measurement, and CT calculation. This predictive model can be used to reliably predict ureteral length based on clinical and radiological factors and may thus be a useful tool to help determining the optimal length of ureteral stent.

Increased neutrophil-to-lymphocyte ratio is associated with disease-specific mortality in patients with penile cancer.

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR), a simple marker of the systemic inflammatory response, has been demonstrated to correlate with patient outcomes for various solid malignancies. We investigated the utility of the pretreatment NLR as a prognosticator in patients who presented with penile cancer. METHODS: A total of 41 patients who underwent complete blood count with differential and subsequent radical penectomy from 1988 to 2014 were analyzed. We assessed the correlation between the NLR and the prognosis of penile cancer. RESULTS: The median and mean (± SD) NLRs in 41 penile cancer patients were 3.42 and 5.03 ± 4.99, respectively. Based on the area under receiver operator characteristic curve, the cut-off value of NLR was determined to be 2.82. Patients with a high NLR (≥2.82) showed a significantly poorer cancer-specific survival (p = 0.023) than those with a low NLR. CONCLUSIONS: The pretreatment NLR may function as a biomarker that precisely predicts the prognosis in patients with penile cancer.

Risk factors of systemic inflammation response syndrome after endoscopic combined intrarenal surgery in the modified Valdivia position.

OBJECTIVE: To identify risk factors of developing systemic inflammation response syndrome after endoscopic combined intrarenal surgery in the modified Valdivia position for renal stone treatment. METHODS: We retrospectively analyzed 370 consecutive patients who underwent endoscopic combined intrarenal surgery procedures in the modified Valdivia position to treat renal stones. Antibiotic therapy based on preoperative urine cultures was administered to all patients from induction of anesthesia until at least postoperative day 3. Postoperative systemic inflammation response syndrome was diagnosed if the patient met two or more systemic inflammation response syndrome criteria. A multivariate logistic regression model with backward selection was used to evaluate the relationships between the incidence of systemic inflammation response syndrome after endoscopic combined intrarenal surgery and other clinical factors. RESULTS: Of the 370 patients, 61 patients (16.5%) were diagnosed with systemic inflammation response syndrome after endoscopic combined intrarenal surgery. Significant differences were found between the non-systemic inflammation response syndrome and systemic inflammation response syndrome groups with regard to female sex (29.8% vs 44.3%, P = 0.027), history of febrile urinary tract infection (16.5% vs 32.8%, P = 0.015) and number of involved calyces (2.68 vs 4.1, P < 0.001). Multivariate analysis found three independent predictors of postoperative systemic inflammation response syndrome: the number of involved calyces (P = 0.017), stone surface area (P = 0.021) and history of febrile urinary tract infection (P = 0.005). CONCLUSIONS: The number of involved calyces larger than four, stone surface area >500 mm(2) and a history of febrile urinary tract infection independently predicted the development of systemic inflammation response syndrome after endoscopic combined intrarenal surgery. This is the first study to identify the independent predictors of systemic inflammation response syndrome after endoscopic combined intrarenal surgery in the modified Valdivia position.

Predicting the mineral composition of ureteral stone using non-contrast computed tomography.

We investigated the correlation between computed tomography (CT) density of ureteral stones and their mineral composition. A total of 346 patients who underwent ureteroscopic lithotripsy for calculi all fragments of which were acquired at a single institution from 2009 to 2011 were analyzed. The maximum and mean CT densities were measured preoperatively. A mineral analysis revealed calcium oxalate in 203 (58.7 %), mixed calcium oxalate and calcium phosphate in 78 (23.0 %), calcium phosphate in 18 (5.2 %), uric acid in 8 (2.3 %), struvite in 3 (0.9 %), and cysteine in 5 (1.4 %). The mean Hounsfield units (HUs) of the CT density were 1046 HUs in calcium oxalate, 1101 HUs in mixed calcium oxalate and calcium phosphate, 835 HUs in calcium phosphate, 549 HUs in uric acid, 729 HUs in struvite, and 698 HUs in cystine. The HUs in calcium oxalate were significantly higher than those in uric acid (p < 0.01) and struvite (p < 0.01). Those in monohydrate stones were significantly higher, compared with dehydrate stones (p < 0.05). We analyzed the largest number of stones than each published study to correlate their mineral composition and CT density. Calcium component stones showed significantly higher CT densities than other types.

Retrograde intrarenal surgery for urinary stone disease in patients with solitary kidney: A retrospective analysis of the efficacy and safety.

OBJECTIVES: To compare outcomes of retrograde intrarenal surgery for urolithiasis between patients with solitary kidneys and patients who have single-side urolithiasis with bilateral kidneys. METHODS: We retrospectively analyzed outcomes of retrograde intrarenal surgery in solitary kidney patients (group A) carried out during 2007-2014, and in patients with bilateral kidneys with comparable stone burdens (group B). Stone-free status was defined as no residual fragment on computed tomography 1 month later. RESULTS: There were 19 patients in group A (mean age 62.5 ± 18.4 years, range 14-76 years). The mean stone diameter and burden were 6.0 mm (range 3-24 mm) and 10.42 ± 6.92 mm, respectively. The stone-free rate was 94.7%, and no repeat procedure was required. The glomerular filtration rate tended to rise post-surgery (postoperative day 1: 48.67 ± 15.92 mL/min, 100.2%, P = 0.940; postoperative month 1: 51.32 ± 16.90 mL/min, 105.7%, P = 0.101) compared with preoperative rates. The stone-free rate and surgery time were not significantly different between the two groups, although post-surgical hospitalization time was longer for group A (4.05 vs 3.08 days, P = 0.037). The change in glomerular filtration rate was not significantly different between groups A and B (postoperative day 1: +0.101 vs +0.547 mL/min, respectively, P = 0.857; postoperative month 1: +2.749 vs 3.161 mL/min, respectively, P = 0.882). No significant difference was found in terms of complication rate. CONCLUSIONS: Retrograde intrarenal surgery in solitary kidney patients is as safe and effective as in bilateral kidney patients.

[Tubeless Percutaneous Nephrolithotomy].

We assessed our initial experience with tubeless percutaneous nephrolithotomy (PCNL). Between February 2011 and December 2013, we performed 155 tubeless PCNL and 54 standard PCNL in which nephrostomy tubes were used postoperatively. Tubeless PCNL was performed when the presence of residual fragments, bleeding, and extravasation were excluded intraoperatively. The incidence of complications, hospital stay duration, analgesic requirements, visual analog scale score, decrease in hemoglobin levels, and stone-free rates were compared between the two groups. The mean hospital stay after tubeless PCNL was shorter (5.1 days) than that after standard PCNL (6.8 days, P＜0.05). Transient fever was seen in 20 patients (13.8%) in the tubeless PCNL group and 12 patients (25.5%) in the standard PCNL group. Tubeless PCNL is a safe and effective procedure, and hospital stay is shorter with tubeless PCNL than with standard PCNL.

Development and Internal Validation of a Classification System for Predicting Success Rates After Endoscopic Combined Intrarenal Surgery in the Modified Valdivia Position for Large Renal Stones.

OBJECTIVE: To identify preoperative predictors and to develop a classification system for predicting success rate after endoscopic combined intrarenal surgery (ECIRS) in the modified Valdivia position for renal stone treatment. PATIENTS AND METHODS: We retrospectively analyzed 329 consecutive, single-session ECIRS procedures undertaken in the modified Valdivia position to treat renal stones. The successful status after surgery was determined at 1 month postoperatively using noncontrast computed tomography and was defined as the absence of stones or residual fragments measuring <4 mm. The preoperative factors analyzed included the stone statuses, which were determined by noncontrast computed tomography, and the patients' characteristics. A multivariate logistic regression model with backward selection was used to evaluate the relationships between the preoperative factors and a successful status after ECIRS, and a classification system was developed to predict a stone-free status based on the preoperative factors. RESULTS: The overall successful outcome rate was 65.3%. Multivariate analysis determined 2 independent predictors of ECIRS outcomes, namely, the stone surface areas (P = .001) and the number of involved calyces (P = .001). These parameters were used to develop the classification system for predicting the successful status after ECIRS. CONCLUSION: Stone surface areas and the number of involved calyces independently predicted the successful status after ECIRS. This is the first study to identify the independent predictors and develop a classification table for predicting success rates after ECIRS in the modified Valdivia position.