Long-Term Outcomes of Longitudinal Efficacy Study With Tolvaptan in ADPKD.

INTRODUCTION: The effects of long-term and uninterrupted tolvaptan treatment on autosomal dominant polycystic kidney disease (ADPKD) are unclear. Therefore, a more than 3-year continuous treatment study was performed. METHODS: From the Kyorin University cohort, 299 patients were surveyed and 179 patients were indicated for tolvaptan having a total kidney volume (TKV) ≥750 ml, TKV slope ≥5%/yr, and estimated glomerular filtration rate (eGFR) ≥15 ml/min per 1.73 m2. Among 179 patients, 118 patients consented to the study. RESULTS: Retrospective pretreatment and prospective on-treatment periods had a median of 1.8 and 4.0 years, respectively. During the 5 treatment-years, the log10(TKV) slope/yr decreased from the pretreatment period (P < 0.0001) and the estimated height-adjusted TKV growth rate α (eHTKV-α, %/yr) decreased from baseline (P < 0.0001). The decline in eGFR improved in female patients (P < 0.0001), but not in males (P = 0.6321). Furthermore, during the 5 treatment-years, eGFR remained significantly better in the group with a percent decrease in eHTKV-α from baseline to the first treatment-year ≥ the median (2.94%) than in the group with a decrease <2.94%. The free-water clearance was higher in males than in females irrespective of treatment. CONCLUSION: The TKV growth rate decreased in 4 years with tolvaptan in both sexes. The insignificant effects of tolvaptan on the eGFR slope in males were likely due to androgen stimulation of cystogenesis and analytical difficulty of longitudinal changes in nonlinear trajectories of eGFR. The larger decrease in eHTKV-α in the first year was related to a better renal prognosis. The vasopressin-mediated water reabsorption was activated more in females than males irrespective of tolvaptan administration.

Japanese linguistic validation of the ureteral stent symptom questionnaire.

OBJECTIVE: We validated the Japanese version of the ureteral stent symptom questionnaire in patients with an indwelling ureteric stent. METHODS: The English version of the ureteral stent symptom questionnaire was translated into Japanese using a multistep process by three urologists and two independent translators. A total of 70 patients with indwelling ureteral stents completed the Japanese ureteral stent symptom questionnaire, as well as validated instruments, namely, the International Prostate Symptom Score or Overactive Bladder Symptom Score and the EuroQoL 5-dimension questionnaires. Patients completed questionnaires at 2 weeks after stent insertion and 4 weeks after stent removal. The second group included 87 healthy individuals who agreed to complete the questionnaires. The reliability of the Japanese version was evaluated for internal consistency using Cronbach's α test. Psychometric properties of the questionnaire were analyzed, and included convergent validity, sensitivity to change and discriminant validity. RESULTS: A total of 70 cases and 87 controls were suitable for the analysis. A comparison of patients with ureteric stents and healthy individuals was carried out, and the convergent validity determined by the correlation between other instruments and the corresponding ureteral stent symptoms questionnaire domains was satisfactory (P < 0.05). Internal consistencies (Cronbach's α coefficients 0.73-0.80) were satisfactory, except for the sexual matters domain. Test-retest reliability was good, except for the sexual matters domain (Spearman's coefficient 0.71-0.93). CONCLUSIONS: The Japanese version of the ureteral stent symptom questionnaire proved to be a reliable and robust instrument for the evaluation of ureteral stent-associated morbidity for both men and women.

PKD1-Associated Arachnoid Cysts in Autosomal Dominant Polycystic Kidney Disease.

OBJECTIVES: the prevalence of intracranial aneurysms and arachnoid cysts is higher in patients with autosomal dominant polycystic kidney disease (ADPKD) than in the general population. A genotype correlation was reported for intracranial aneurysms, but it is unclear for arachnoid cysts. Therefore, the genotype correlation with intracranial aneurysms and arachnoid cysts was investigated in ADPKD. MATERIALS AND METHODS: intracranial aneurysms and arachnoid cysts were screened by magnetic resonance imaging (MRI), and PKD genotypes were examined using next-generation sequencing for 169 patients with ADPKD. RESULTS: PKD1-, PKD2- and no-mutation were identified in 137, 24 and 8 patients, respectively. Intracranial aneurysms and arachnoid cysts were found in 34 and 25 patients, respectively, with no significant difference in frequency. Genotype, sex, estimated glomerular filtration rate and age at ADPKD diagnosis significantly affected the age at brain MRI. The proportional hazard risk analyzed using the age at brain MRI adjusted by these four variables was 5.0-times higher in the PKD1 group than in the PKD2 group for arachnoid cysts (P = 0.0357), but it was not different for intracranial aneurysms (P = 0.1605). Arachnoid cysts were diagnosed earlier in the PKD1 group than in the PKD2 group (54.8 vs 67.7 years, P = 0.0231), but no difference was found for intracranial aneurysms (P = 0.4738) by Kaplan-Meier analysis. CONCLUSIONS: this study demonstrated the correlation between arachnoid cysts and PKD1 mutation. The reported association of arachnoid cysts with advanced renal disease may be due to the common correlation of these factors with PKD1 mutation.

Factors predicting decline in renal function and kidney volume growth in autosomal dominant polycystic kidney disease: a prospective cohort study (Japanese Polycystic Kidney Disease registry: J-PKD).

BACKGROUND: Factors affecting decline in renal function and cyst growth in patients with autosomal polycystic kidney disease (ADPKD) are not fully described, particularly in Japan. METHODS: This was the first multi-facility, prospective, observational cohort study conducted in ADPKD patients at 14 centers in Japan. Patients in the J-PKD registry were assessed from December 2009 to June 2012 (follow-up until June 2017). Patients' data including estimated glomerular filtration rate (eGFR) and total kidney volume (TKV) were assessed initially and a maximum of five times annually. Contributing factors to eGFR decline and TKV growth were identified using multiple linear regression analysis. RESULTS: Of the 340 patients in the J-PKD registry, data analysis was performed for 192 patients in whom serial changes for both eGFR and TKV were obtained. eGFR slope, eGFR change, and TKV change values were as follows: - 2.7 (- 4.2 to - 1.5) (ml/min/1.73 m2/year), - 5.0 (- 9.6 to - 2.3) (%/year), and 4.78 (0.86-8.22) (%/year), respectively. Lower high-density lipoprotein (HDL) cholesterol was an independent predictor of eGFR decline, using both eGFR slope and change (P = 0.04, P = 0.02, respectively), whereas lower hemoglobin and higher uric acid were significantly associated with greater eGFR change only (P = 0.02, P = 0.002, respectively). Younger age and higher fasting blood sugar were independent predictors of greater TKV change (P = 0.01, P = 0.02, respectively). CONCLUSIONS: This real-world study in Japan identified risk factors for renal function decline in ADPKD patients. These included lower HDL cholesterol, lower hemoglobin and higher uric acid for eGFR decline, and youth and higher blood sugar levels for TKV growth.

Estimation of Changes in Kidney Volume Growth Rate in ADPKD.

INTRODUCTION: In the Mayo Imaging Classification (MIC) for autosomal dominant polycystic kidney disease (ADPKD), the height-adjusted total kidney volume (HtTKV) growth rate is estimated for classification. Estimated HtTKV slope, termed as eHTKV-α, is calculated by the equation [HtTKV at age t] = K(1+α/100)(t-A), where K = 150 and A = 0 are used in MIC. If eHTKV-α is nearly stable during a standard-of-care period, the change in eHTKV-α from baseline can be used for estimation of the treatment effect on the HtTKV slope. METHODS: The constancy of eHTKV-α (A = 0 and K = 150) was evaluated using 453 placebo-assigned subjects in the Tolvaptan Efficacy and Safety in Management of ADPKD and Its Outcomes (TEMPO) 3:4 trial. A and K were sought out respectively by a converged pattern of regression lines of log10(HtTKV) plotted against age for subgroups divided according to MIC, and by change in eHTKV-α from baseline. A total of 239 standard-of-care patients from the Kyorin University Cohort (KUC) served as validation. Changes in eHTKV-α from baseline were evaluated in 809 tolvaptan-treated subjects in TEMPO 3:4. RESULTS: In placebo-assigned subjects, eHTKV-α (A = 0 and K = 150) changed significantly from baseline at the third year. As regression lines of placebo-assigned subgroups converged around age 0, A was set as 0, which was confirmed by KUC. K = 130 was selected because of minimal change in eHTKV-α from baseline. The KUC validated the constancy of eHTKV-α (A = 0 and K = 130) but not that of eHTKV-α (A=0 and K=150). In tolvaptan-treated subjects, eHTKV-α remained significantly lower than baseline for 3 years. CONCLUSIONS: eHTKV-α (A = 0 and K = 130) was nearly stable from baseline through follow-up in standard-of-care adults. Treatment effects on the HtTKV slope can be estimated by changes in eHTKV-α from baseline.

A Novel Flexible Ureteroscope with Omnidirectional Bending Tip Using Joystick-Type Control Unit (URF-Y0016): Initial Validation Study in Bench Models.

Purpose: The conventional flexible ureteroscope has limited access into the lower calix and often causes biomechanical stress to surgeons. Recently, a novel flexible ureteroscope with an omnidirectional bending tip with a joystick-type control unit (URF-Y0016; Olympus, Japan) was developed. We verified the operability and ergonomics of the URF-Y0016 compared with that of the conventional flexible ureteroscope (URF-P6) in bench models. Materials and Methods: Twenty-five medical students with no experience in performing ureteroscopic manipulation were randomly assigned to URF-Y0016 and URF-P6 leading groups in a crossover study. The task was performed using a simple model as an exploratory experiment and an artificial kidney model as an evaluation experiment. We compared the task completion times of both groups, while the factors influencing task completion time were entered into a multivariate model. The ergonomics of endourology were compared using a validated questionnaire. Results: The task completion time in the URF-Y0016 group was significantly shorter than in the URF-P6 group (p < 0.001). The URF-Y0016 group showed no difference in task completion time between each renal calix, whereas in the URF-P6 group the task completion time in the lower calix was significantly longer than that in other calices (p < 0.001). In multivariate analysis, the model of flexible ureteroscope used significantly influenced the task completion time (p < 0.001). The ergonomics of the URF-Y0016 group were significantly better than those of the URF-P6 group (p = 0.001). Conclusions: URF-Y0016 may offer benefits in ureteroscopy performance over the conventional flexible ureteroscope.

Age- and height-adjusted total kidney volume growth rate in autosomal dominant polycystic kidney diseases.

BACKGROUND: The Mayo Clinic Image Classification (MIC) was proposed as a renal prognosis prediction model for autosomal dominant polycystic kidney disease (ADPKD). MIC is based on the assumption of exponential constant increase in height-adjusted total kidney volume (HtTKV). HtTKV growth rate is calculated by one-time measurement of HtTKV and age. We named it as an age-adjusted HtTKV growth rate (AHTKV-α). AHTKV-α was compared with HtTKV slope measured by at least two HtTKV values. METHODS: Comparison of repeatability between AHTKV-α and HtTKV slope, correlation of subgroups divided according to baseline AHTKV-α and HtTKV slope with disease manifestations, estimated glomerular filtration rate (eGFR) slope, and renal survival were analyzed in 296 patients with ADPKD. PKD genotype influences were compared between AHTKV-α and HtTKV slope in 88 patients with characterized PKD mutations. RESULTS: Absolute differences between baseline and follow-up measures were significantly larger for the HtTKV slope than for AHTKV-α (P < 0.0001). From baseline AHTKV-α-based subgroups A-E according to MIC, disease manifestations occurred earlier and future eGFR slopes became steeper (P < 0.0001). Multivariate hazard ratios of renal survival differed significantly among baseline AHTKV-α-based subgroups. Inter-subgroup differences in these predictors were less evident during baseline HtTKV slope-based classification. AHTKV-α values, but not HtTKV slopes, were significantly higher for PKD1 mutation carriers than for PKD2 mutation carriers (P < 0.0001). CONCLUSION: MIC is a good renal prediction model applicable to Japanese patients also. AHTKV-α can be a more sensitive and reliable indicator in TKV growth rate than HtTKV slope.

Optimal equation for estimation of glomerular filtration rate in autosomal dominant polycystic kidney disease: influence of tolvaptan.

BACKGROUND: The reliability of various equations for estimating the GFR in ADPKD patients and the influence of tolvaptan on the resulting estimates have not been examined when GFR is calculated on the basis of inulin clearance. METHODS: We obtained baseline and on-tolvaptan measured GFRs (mGFRs), calculated on the basis of inulin clearance, in 114 ADPKD, and these mGFRs were compared with eGFRs calculated according to four basic equations: the MDRD, CKD-EPI, and JSN-CKDI equations and the Cockcroft-Gault formula, as well as the influence of tolvaptan and of inclusion of cystatin C on accuracy of the results. Accuracy of each of the seven total equations was evaluated on the basis of the percentage of eGFR values within mGFR ± 30% (P30). RESULTS: mGFRs were distributed throughout CKD stages 1-5. Regardless of the CKD stage, P30s of the MDRD, CKD-EPI, and JSN-CKDI equations did not differ significantly between baseline values and on-tolvaptan values. In CKD 1-2 patients, P30 of the CKD-EPI equation was 100.0%, whether or not the patient was on-tolvaptan. In CKD 3-5 patients, P30s of the MDRD, CKD-EPI, and JSN-CKDI equations were similar. For all four equations, regression coefficients and intercepts did not differ significantly between baseline and on-tolvaptan values, but accuracy of the Cockcroft-Gault formula was inferior to that of the other three equations. Incorporation of serum cystatin C reduced accuracy. CONCLUSIONS: The CKD-EPI equation is most reliable, regardless of the severity of CKD. Tolvaptain intake has minimal influence and cystatin C incorporation does not improve accuracy.

Sexual activity and quality of life in Japanese pelvic organ prolapse patients after transvaginal mesh surgery.

AIM: This study aimed to evaluate sexual activity and quality of life (QOL) after transvaginal mesh (TVM) surgery in Japanese patients with pelvic organ prolapse (POP). The objective cure rate and associated complications were also investigated. METHODS: The cases of patients who underwent TVM surgery were retrospectively analyzed. QOL was assessed using the Prolapse Quality of Life Questionnaire (P-QOL), and sexual function was evaluated using the Female Sexual Function Index (FSFI) before surgery and 12 months after surgery. RESULTS: A total of 237 patients completed the planned follow-up examinations. All P-QOL domains were significantly improved after surgery. In total, 6 (2.5%), 5 (2.1%), 13 (5.5%), 4 (1.7%) and 1 (0.4%) patients developed recurrent POP, mesh extrusion, de novo stress urinary incontinence, inguinal pain and de novo dyspareunia, respectively. Before surgery, 124 of the 237 patients (52.3%) refused to complete the FSFI because they had not engaged in any sexual activity. Among the 113 patients who completed the FSFI, 13 (11.5%) were sexually active. After surgery, 79 patients completed the FSFI, and 14 (17.7%) were sexually active. The overall scores for sexual function and arousal were significantly improved after surgery. CONCLUSION: Patients who underwent TVM surgery at our institution exhibited quite low sexual activity levels both before and after the operation. But TVM surgery achieved good QOL outcomes, a high success rate and a low complications rate at 12 months in Japanese POP patients. TVM implantation for POP is safe and effective in sexually inactive patients.

Vesicoenteric Fistula Arising from an Adenocarcinoma of Ectopic Pancreatic Tissue in a Meckel Diverticulum.

We report a case of a vesicoenteric fistula arising from an adenocarcinoma of ectopic pancreatic tissue in a Meckel diverticulum in a 58-year-old man. The patient suffered from refractory micturition pain and increased urinary frequency. Computerized tomography with a contrast agent showed a ring-shaped enhanced mass near the dome of the urinary bladder. Magnetic resonance imaging showed a cystic mass close to the urinary bladder with partly irregular wall and fistula formation to the urinary bladder. Surgical findings showed a Meckel diverticulum in the ileum, which formed a fistula with the urinary bladder, and Meckel diverticulectomy and partial cystectomy were performed. Histological findings revealed a vesicoenteric fistula arising from a papillary adenocarcinoma of ectopic pancreatic tissue in a Meckel diverticulum. The patient has survived without recurrence for more than 4 years since surgery.

AR-V7 in circulating tumor cells cluster as a predictive biomarker of abiraterone acetate and enzalutamide treatment in castration-resistant prostate cancer patients.

OBJECTIVE: We examined whether androgen receptor splice variant 7 (AR-V7) in circulating tumor cell(CTC)clusters can be used to predict survival in patients with bone metastatic castration resistant-prostate cancer (mCRPC) treated with abiraterone or enzalutamide. METHODS: We retrospectively enrolled 98 patients with CRPC on abiraterone or enzalutamide, and investigated the prognostic value of CTC cluster detection (+ v -) and AR-V7 detection (+ v -) using a CTC cluster detection - based AR-V7 mRNA assay. We examined ≤50% prostate-specific antigen (PSA) responses, PSA progression-free survival (PSA-PFS), clinical and radiological progression-free survival (radiologic PSF), and overall survival (OS). We then assessed whether AR-V7 expression in CTC clusters identified after On-chip multi-imaging flow cytometry was related to disease progression and survival after first-line systemic therapy. RESULTS: All abiraterone-treated or enzalutamide-treated patients received prior docetaxel. The median follow-up was 20.7 (range: 3.0-37.0) months in the abiraterone and enzalutamide cohorts, respectively. Forty-nine of the 98 men (50.0%) were CTC cluster (-), 23 of the 98 men (23.5%) were CTC cluster(+)/AR-V7(-), and 26 of the 98 men (26.5%) were CTC cluster(+)/AR-V7(+). CTC cluster(+)/AR-V7(+) patients were more likely to have EOD ≥3 at diagnosis (P = 0.003), pain (P = 0.023), higher alkaline phosphatase levels (P < 0.001), and visceral metastases (P < 0.001). On multivariable analysis, pretherapy CTC cluster(+), CTC cluster(+)/AR-V7(-), and ALP >UNL were independently associated with a poor PSA-PFS, radiographic PFS, and OS in abiraterone-treated patients and enzalutamide-treated patients. CONCLUSION: The CTC clusters and AR-V7-positive CTC clusters detected were important for assessing the response to abiraterone or enzalutamide therapy and for predicting disease outcome.

A potentially crucial role of the PKD1 C-terminal tail in renal prognosis.

BACKGROUND: Autosomal dominant polycystic disease (ADPKD) often results in renal failure. Recently, allelic influences of PKD1 mutation types on renal survival were extensively investigated. Here, we analyzed integrated influences of PKD1 mutation types and positions on renal survival. METHODS: We included 338 (82 pedigrees) and 72 (12 pedigrees) patients with PKD1 and PKD2 mutations, respectively, identified through comprehensive gene analysis of 101 probands with ADPKD. Genetic testing was performed using next-generation sequencing, long-range PCR, and multiplex ligation-dependent probe amplification. Pathogenic mutations were identified by a software package-integrated seven databases and provided access to five cloud-based computing systems. RESULTS: Mean renal survivals of carriers with PKD1 non-truncating-type mutations at positions upstream of G-protein-coupled receptor proteolytic site (GPS-upstream domain), transmembrane domain, or cytoplasmic C-terminal tail (CTT) domain were 70.2, 67.0, and 50.1 years, respectively (P < 0.0001); renal survival was shorter for mutation positions closer to CTT domain, suggesting its crucial role in renal prognosis. Furthermore, in truncating-type mutations, strong inactivation is anticipated on nucleotides downstream from the mutation site, implying CTT domain inactivation irrespective of mutation site. Shorter mean renal survival was found for PKD1 truncating-type than non-truncating-type mutation carriers (P = 0.0348); mean renal survival was not different between PKD1 3'- and 5'-region truncating-type mutation carriers (P = 0.4375), but was shorter in PKD1 3'-region than in 5'-region non-truncating-type mutation carriers (P = 0.0014). Variable strength of CTT domain inactivation might account for these results. CONCLUSIONS: Aforementioned findings indicate that CTT domain's crucial role in renal prognosis needs further investigation by larger studies (ClinicalTrials.gov; NCT02322385).

Long-term Persistence with Mirabegron versus Solifenacin in Women with Overactive Bladder: Prospective, Randomized Trial.

OBJECTIVES: To compare persistence with medication and the reasons for discontinuation of mirabegron or solifenacin therapy up to12 months in women with overactive bladder (OAB). METHODS: Female OAB patients who presented to women's urology clinics were enrolled in a prospective, randomized, two-arm study. Patients were randomized to receive mirabegron at 25-50 mg (n = 76) or solifenacin at 2.5-5 mg (n = 72). The persistence rate and the reasons for discontinuation were investigated up to 12 months. RESULTS: The 12-month persistence rate was 12.2% in the mirabegron group versus 20.1% in the solifenacin group and there were no significant differences of the persistence rates during the study (n.s). Patients discontinued treatment because of lack of efficacy (21.6%), spontaneous improvement (18.2%), and side-effects (17.6%), while 19.6% were lost to follow up. Discontinuation due to side-effects was significantly more frequent in the solifenacin group than the mirabegron group (27.3 vs. 7.9%, P < 0.05). In contrast, discontinuation due to lack of efficacy was significantly more frequent in the mirabegron group than the solifenacin group (36.8 vs. 5.6%, P < 0.05). CONCLUSIONS: This study demonstrated low persistence rates over 12 months for both mirabegron and solifenacin, although the reasons for discontinuation were somewhat different.

Distinguishing testicular torsion from torsion of the appendix testis by clinical features and signs in patients with acute scrotum.

PURPOSE: Many physicians encounter confusion and difficulty in distinguishing testicular torsion (TT) from torsion of the appendix testis (TAT) in patients with acute scrotum because of the overlapping signs and symptoms. The objective of our study was to evaluate the clinical features and signs that can help distinguish TT from TAT. PATIENTS AND METHODS: We performed a retrospective study of patients with surgically confirmed TT and TAT at our institute from January 1990 to December 2013. Clinical findings, physical examination findings, climatic conditions, laboratory data, and color Doppler ultrasound (CDUS) findings were compared between the TT and TAT groups. RESULTS: Seventy patients were included in this study (49 with TT and 21 with TAT). Patients with TT were significantly older than those with TAT (p < 0.001). The ambient temperature at onset was significantly lower in patients with TT than in patients with TAT (p = 0.038). Testicular swelling, high-riding testes, onset during sleep, high leukocyte counts, and high creatine phosphokinase levels were significantly more common in patients with TT than with TAT (p = 0.021, 0.032, 0.006, 0.003, and 0.043, respectively). Multivariate analysis showed that age and onset during sleep were significant independent factors for detection of TT. Eight patients (16.3%) underwent preoperative CDUS evaluation, and an absent or decreased blood signal in the involved testes was significantly correlated with the presence of TT (p = 0.018). CONCLUSION: In clinical features, age and onset during sleep might be helpful to distinguish TT from TAT. When supported by findings, urgent surgical exploration is warranted in patients with suspected TT based on symptoms and CDUS features.

Relationship between intracranial aneurysms and the severity of autosomal dominant polycystic kidney disease.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is a hereditary kidney disease characterized by the progressive enlargement of innumerable renal cysts. Although the association of intracranial aneurysms (ICANs) with ADPKD is well known, the relationship between the ICAN and the disease severity including total kidney volume (TKV) and estimated glomerular filtration rate (eGFR) is poorly understood. METHODS: We screened 265 patients with ADPKD (mean age, 48.8 years; range, 14.9-88.3 years) with MR angiography. The patients with a past history related to ICANs were excluded from the study. The incidence and characteristics of ICAN in patients with ADPKD were evaluated. TKV was measured by volumetric analyses of MR imaging. RESULTS: We detected 65 ICANs in 49 patients (37 women and 12 men, mean age, 52.7 years; range, 20.4-86 years). The incidence of ICANs was 18.5% and female patients had was higher incidence (23.1%) than male patients (11.4%) (p = 0.02). An age of those with ICANs was significantly higher than those without (p = 0.006), and the cumulative risk of diagnosis of ICANs increased with age. TKV was significantly larger in those with ICANs than those without (p = 0.001), but eGFR was not different between two groups (p = 0.07). By multivariate analyses, only TKV was significantly related to the development of ICANs (p = 0.02). CONCLUSIONS: The incidence of ICANs increased with age, was higher in females, and correlated with kidney enlargement in patients with ADPKD. Necessity of screening ICANs would be particularly high in elderly women with large kidneys.

Intratumor Heterogeneity in Primary Kidney Cancer Revealed by Metabolic Profiling of Multiple Spatially Separated Samples within Tumors.

Metabolic alteration constitutes a hallmark of cancer. Glycolysis and antioxidant pathways in kidney cancer are elevated, with frequent mutation of the VHL gene. Intratumor genetic heterogeneity has been recently demonstrated in kidney cancer. However, intratumor metabolic heterogeneity has not been investigated. Here, we used global metabolomics analysis and tissue slice tracer studies to demonstrate that different portions of a human primary kidney tumor possess different metabolic characteristics and drug sensitivity. Pyruvate levels were elevated and pyruvate metabolism was altered in some tumor sections. These observations indicated that pyruvate metabolism may constitute a possible vulnerability of kidney cancer; indeed, pyruvate stimulated the growth of primary kidney cancer cells and pharmacological inhibition of pyruvate transporters slowed the growth of patient-derived kidney tumors in mice. These findings deepen our understanding of the intratumor metabolic heterogeneity of kidney cancer and may inform novel therapeutic approaches in human kidney cancer.

Epidermal Growth Factor Receptor Status in Circulating Tumor Cells as a Predictive Biomarker of Sensitivity in Castration-Resistant Prostate Cancer Patients Treated with Docetaxel Chemotherapy.

OBJECTIVE: We examined whether epidermal growth factor receptor (EGFR) expression in circulating tumor cells (CTCs) can be used to predict survival in a population of bone-metastatic castration-resistant prostate cancer (mCRPC) patients treated with docetaxel chemotherapy. METHODS: All patients with mCRPC who had experienced treatment failure with androgen-deprivation therapy and had received docetaxel chemotherapy were eligible. CTCs and EGFR expression in CTCs were enumerated with the CellSearch System in whole blood. This system is a semi-automated system that detects and enriches epithelial cells from whole blood using an EpCAM antibody-based immunomagnetic capture. In addition, the EGFR-positive CTCs were assessed using CellSearch® Tumor Phenotyping Reagent EGFR. RESULTS: The median CTC count at baseline before starting trial treatment was eight CTCs per 7.5 mL of blood (range 0-184). There were 37 patients (61.7%) who had ≥5 CTCs, with median overall survival of 11.5 months compared with 20.0 months for 23 patients (38.3%) with <5 CTCs (p < 0.001). A total of 15 patients (40.5%, 15/37) with five or more CTCs were subjected to automated immunofluorescence staining and cell sorting for EGFR protein. Patients with EGFR-positive CTCs had a shorter overall survival (OS) (5.5 months) than patients with EGFR-negative CTCs (20.0 months). CTCs, EGFR-positive CTCs, and alkaline phosphatase (ALP) were independent predictors of overall survival time (p = 0.002, p < 0.001, and p = 0.017, respectively). CONCLUSION: CTCs may be an independent predictor of OS in CRPC treated with docetaxel chemotherapy. The EGFR expression detected in CTCs was important for assessing the response to chemotherapy and predicting disease outcome.

Technical Evaluation: Identification of Pathogenic Mutations in PKD1 and PKD2 in Patients with Autosomal Dominant Polycystic Kidney Disease by Next-Generation Sequencing and Use of a Comprehensive New Classification System.

Genetic testing of PKD1 and PKD2 is expected to play an increasingly important role in determining allelic influences in autosomal dominant polycystic kidney disease (ADPKD) in the near future. However, to date, genetic testing is not commonly employed because it is expensive, complicated because of genetic heterogeneity, and does not easily identify pathogenic variants. In this study, we developed a genetic testing system based on next-generation sequencing (NGS), long-range polymerase chain reaction, and a new software package. The new software package integrated seven databases and provided access to five cloud-based computing systems. The database integrated 241 polymorphic nonpathogenic variants detected in 140 healthy Japanese volunteers aged >35 years, who were confirmed by ultrasonography as having no cysts in either kidney. Using this system, we identified 60 novel and 30 known pathogenic mutations in 101 Japanese patients with ADPKD, with an overall detection rate of 89.1% (90/101) [95% confidence interval (CI), 83.0%-95.2%]. The sensitivity of the system increased to 93.1% (94/101) (95% CI, 88.1%-98.0%) when combined with multiplex ligation-dependent probe amplification analysis, making it sufficient for use in a clinical setting. In 82 (87.2%) of the patients, pathogenic mutations were detected in PKD1 (95% CI, 79.0%-92.5%), whereas in 12 (12.8%) patients pathogenic mutations were detected in PKD2 (95% CI, 7.5%-21.0%); this is consistent with previously reported findings. In addition, we were able to reconfirm our pathogenic mutation identification results using Sanger sequencing. In conclusion, we developed a high-sensitivity NGS-based system and successfully employed it to identify pathogenic mutations in PKD1 and PKD2 in Japanese patients with ADPKD.

Development and Validation of a Novel Recurrence Risk Stratification for Initial Non-muscle Invasive Bladder Cancer in Asia.

BACKGROUND: Some risk classifications to determine prognosis of patients with non-muscle invasive bladder cancer (NMIBC) have disadvantages in the clinical setting. We investigated whether the EORTC (European Organization for Research and Treatment of Cancer) risk stratification is useful to predict recurrence and progression in Japanese patients with NMIBC. In addition, we developed and validated a novel, and simple risk classification of recurrence. METHODS: The analysis was based on 1085 patients with NMIBC at six hospitals. Excluding recurrent cases, we included 856 patients with initial NMIBC for the analysis. The Kaplan-Meier method with the log-rank test were used to calculate recurrence-free survival (RFS) rate and progression-free survival (PFS) rate according to the EORTC risk classifications. We developed a novel risk classification system for recurrence in NMIBC patients using the independent recurrence prognostic factors based on Cox proportional hazards regression analysis. External validation was done on an external data set of 641 patients from Kyorin University Hospital. FINDINGS: There were no significant differences in RFS and PFS rates between the groups according to EORTC risk classification. We constructed a novel risk model predicting recurrence that classified patients into three groups using four independent prognostic factors to predict tumour recurrence based on Cox proportional hazards regression analysis. According to the novel recurrence risk classification, there was a significant difference in 5-year RFS rate between the low (68.4%), intermediate (45.8%) and high (33.7%) risk groups (P<0.001). INTERPRETATION: As the EORTC risk group stratification may not be applicable to Asian patients with NMIBC, our novel classification model can be a simple and useful prognostic tool to stratify recurrence risk in patients with NMIBC. FUNDING: None.