The impact of robotic surgery access on the management of patients with clinical stage I kidney tumors.

INTRODUCTION: Robotic surgery is used in the treatment of kidney tumors. We aimed to determine if robotic access was associated with initial choice of management for patients with a clinical stage I kidney mass. METHODS: Patients with a clinical stage I kidney mass were identified from the Canadian Kidney Cancer information system (CKCis) cohort. Sites were classified by year and access to robotic surgery. Associations between robotic access and initial management were determined using logistic regression. Univariable and multivariable analyses were performed, adjusting for tumor size and stage, and presented as relative risks (RR ) or adjusted RR (aRR) and 95% confidence intervals (CI). RESULTS: Overall, 4160 patients were included. Among patients treated with surgery, the proportion of partial nephrectomy compared to radical nephrectomy was significantly higher in robotic sites (77.3% for robotic sites vs. 65.9% for non-robotic sites; RR 1.17, 95% CI 1.12-1.23, p<0.0001; aRR 1.12, 95% CI 1.08-1.17, p<0.0001). Patients receiving partial nephrectomy at sites with robotic access were more likely to receive a minimally invasive approach compared to patients at non-robotic sites (61.4% vs. 50.9%, RR 1.21, 95% CI 1.12-1.30; aRR 1.16, 95% CI 1.08-1.25, p<0.0001). The proportion of patients managed by active surveillance was not significantly different between robotic (405, 16.9%) and non-robotic (258, 14.7%) sites (RR 1.15, 95% CI 0.99-1.32; aRR 0.97, 95% CI 0.84-1.12). CONCLUSIONS: Access to robotic kidney surgery was associated with increased use of partial nephrectomy and minimally invasive partial nephrectomy. Use of active surveillance was similar at robotic and non-robotic institutions. Limitations of this study include lack of data on perioperative complications and cancer recurrence.

Estimated glomerular filtration rate from the renal hypothermia trial: clinical implications.

OBJECTIVE: To assess if estimated glomerular filtration rate (eGFR) can replace measured GFR (mGFR) in partial nephrectomy (PN) trials, using data from a randomised clinical trial. PATIENTS AND METHODS: We conducted a post hoc analysis of the renal hypothermia trial. Patients underwent mGFR with diethylenetriaminepentaacetic acid (DTPA) plasma clearance preoperatively and 1 year after PN. The eGFR was calculated using the 2009 Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine equations incorporating age and sex, with and without race: 2009 eGFRcr(ASR) and 2009 eGFRcr(AS), and the 2021 equation that only incorporates age and sex: 2021 eGFRcr(AS). Performance was evaluated by determining the median bias, precision (interquartile range [IQR] of median bias), and accuracy (percentage of eGFR within 30% of mGFR). RESULTS: Overall, 183 patients were included. Pre- and postoperative median bias and precision were similar between the 2009 eGFRcr(ASR) (-0.2 mL/min/1.73 m2 , 95% confidence interval [CI] -2.2 to 1.7, IQR 18.8; and -2.9, 95% CI -5.1 to -1.5, IQR 15, respectively) and 2009 eGFRcr(AS) (-0.3 mL/min/1.73 m2 , 95% CI -2.4 to 1.5, IQR 18.8; and -3.0, 95% CI -5.7 to -1.7, IQR 15.0, respectively). Bias and precision were worse for the 2021 eGFRcr(AS) (-8.8 mL/min/1.73 m2 , 95% CI -10.9 to -6.3, IQR 24.7; and -12.0, 95% CI -15.8 to -8.9, IQR 23.5, respectively). Similarly, pre- and postoperative accuracy was >90% for the 2009 eGFRcr(ASR) and 2009 eGFRcr(AS) equations. Accuracy was 78.6% preoperatively and 66.5% postoperatively for 2021 eGFRcr(AS). CONCLUSION: The 2009 eGFRcr(AS) can accurately estimate GFR in PN trials and could be used instead of mGFR to reduce cost and patient burden.

Mass spectrometry redefines optimal testosterone thresholds in prostate cancer patients undergoing androgen deprivation therapy.

BACKGROUND: Androgen deprivation therapy (ADT) is the standard of care for prostate cancer treatment. Studies suggest that patients with testosterone levels below 0.7 nM have a longer time to castration resistance. Using the most accurate testosterone measurement method, namely mass spectrometry (MS), we sought to determine if a lower testosterone level under ADT could be associated with longer time to castration resistance. METHODS: This retrospective study included 138 prostate cancer patients undergoing noncurative continuous ADT for which we had access to testosterone measurements assessed by MS. For 108 samples, paired immunoassays (IA) testosterone measurement was available. Primary outcome was time to castration-resistant prostate cancer (CRPC). The Contal and O'Quigley method was used to determine the optimal testosterone castration cut-off point considering the outcome and time-to-event variables. Relationship between testosterone levels assessed either by IA or MS and time to CRPC was evaluated using Cox regression. RESULTS: Mean testosterone level was 0.370 nM by IA and 0.275 nM as assessed by MS. The optimal testosterone cut-off point identified to predict time to CRPC was of 0.705 nM for IA and of 0.270 nM for MS. While no significant difference for time to CRPC was found between patients showing IA testosterone level ≥0.705 nM versus <0.705 nM (hazard ratio [HR]: 1.579; 95% confidence interval [CI]: 0.908-2.745), patients with MS testosterone ≥0.270 nM had an increased risk of progression to CRPC compared to MS testosterone <0.270 nM in univariate (HR: 1.717; 95% CI: 1.160-2.541) and multivariate analysis (HR: 1.662; 95% CI: 1.043-2.648). CONCLUSIONS: The higher sensitivity of MS testosterone measurement methods allows the identification of a lower castration threshold and leads to early identification of patients more likely to progress to CRPC. These patients would likely benefit from treatment intensification by androgen receptor axis-targeted therapies to delay disease progression.

A survey of physician perception and practices regarding pharmacological thromboprophylaxis during chemotherapy for bladder cancer.

INTRODUCTION: Patients with advanced bladder cancer receiving chemotherapy have a high risk of venous thromboembolism (VTE); however, we hypothesized these patients were not routinely offered thromboprophylaxis. The objective of this study was to characterize practice patterns and perceptions of Canadian urologic and medical oncologists, and to identify research needs regarding thromboprophylaxis for patients with bladder cancer. METHODS: An online survey was distributed to Canadian urologic and medical oncologists who manage advanced bladder cancer. The survey explored physician opinions regarding VTE rates, risk stratification scores, thromboprophylaxis use in different treatment settings, and interest in clinical trials. RESULTS: Seventy physicians were invited and 36 (51%) completed the survey, including 20 (56%) urologic oncologists and 16 (44%) medical oncologists. Most respondents (35; 97%) believed that exposure to platinum chemotherapy increases VTE risk. For patients receiving neoadjuvant chemotherapy, 34 (94%) respondents estimated the risk of VTE to be 10% or higher, yet 25 (69%) indicated they do not routinely recommend thromboprophylaxis. Physicians frequently (10; 40%) defer the decision to another physician, while eight (32%) believe there is not enough evidence to guide best management. Similar responses were obtained for metastatic patients. Almost all (94%) respondents were interested in participating in a thromboprophylaxis trial for patients with bladder cancer. CONCLUSIONS: Patients with bladder cancer receiving chemotherapy in Canada are not routinely offered thromboprophylaxis. We found strong interest among Canadian oncologists to participate in clinical trials examining this topic.

Use and duration of antibiotic prophylaxis and the rate of urinary tract infection after radical cystectomy for bladder cancer: Results of a multicentric series.

OBJECTIVES: To assess the rate of urinary tract infection (UTI), the characteristics of the bacterial aetiological agents involved, the type and duration of antibiotics used, and the clinical risk factors of UTI in a multi-institutional cohort of patients who had undergone radical cystectomy (RC). PATIENTS AND METHODS: The pre- and postoperative characteristics of patients who had undergone open RC at 1 of 3 institutions between 2009 and 2015 were analyzed by means of the patient charts. Patients were classified according to the presence or absence of UTI. Analysis of the severity of UTI was based on the EAU/EAU Section of Infections in Urology (ESIU) classification system. The bacterial aetiological agents and their antibiotic susceptibility were also assessed. Factors predicting postoperative UTI were identified using univariable and multivariable logistic regression analysis. RESULTS: Of 217 patients, 42 (19.4%) had developed postoperative UTI, of whom 50% had urosepsis or uroseptic shock. Multivariable analysis showed continent urinary derivation as the only significant predictor of UTI with an odds ratio of 5.03 (95% confidence interval 2.12-11.9, P < 0.001). The duration of perioperative antibiotic prophylaxis was not associated with an increased risk of UTI. Enterococcus was the most commonly isolated bacteria (25.7%), but this species is not covered by the recommended antibiotic prophylaxis. CONCLUSION: Patients with continent urinary diversion after RC have a significantly higher risk of developing UTI. Prolonged perioperative administration of antibiotics does not seem to reduce the risk of UTI. Enterococcus as the most commonly isolated bacteria is not covered by most recommended antibiotic prophylaxis regimens. Therefore different antibiotic regimens should be considered for high-risk patients.

Discordance between testosterone measurement methods in castrated prostate cancer patients.

Failure to suppress testosterone below 0.7 nM in castrated prostate cancer patients is associated with poor clinical outcomes. Testosterone levels in castrated patients are therefore routinely measured. Although mass spectrometry is the gold standard used to measure testosterone, most hospitals use an immunoassay method. In this study, we sought to evaluate the accuracy of an immunoassay method to measure castrate testosterone levels, with mass spectrometry as the reference standard. We retrospectively evaluated a cohort of 435 serum samples retrieved from castrated prostate cancer patients from April to September 2017. No follow-up of clinical outcomes was performed. Serum testosterone levels were measured in the same sample using liquid chromatography coupled with tandem mass spectrometry and electrochemiluminescent immunoassay methods. The mean testosterone levels were significantly higher with immunoassay than with mass spectrometry (0.672 ± 0.359 vs 0.461 ± 0.541 nM; P < 0.0001). Half of the samples with testosterone ≥0.7 nM assessed by immunoassay were measured <0.7 nM using mass spectrometry. However, we observed that only 2.95% of the samples with testosterone <0.7 nM measured by immunoassay were quantified ≥0.7 nM using mass spectrometry. The percentage of serum samples experiencing testosterone breakthrough at >0.7 nM was significantly higher with immunoassay (22.1%) than with mass spectrometry (13.1%; P < 0.0001). Quantitative measurement of serum testosterone levels >0.7 nM by immunoassay can result in an inaccurately identified castration status. Suboptimal testosterone levels in castrated patients should be confirmed by either mass spectrometry or an immunoassay method validated at low testosterone levels and interpreted with caution before any changes are made to treatment management.