Development and validation of a virtual reality transrectal ultrasound guided prostatic biopsy simulator

Objective: We present the design, reliability, face, content andconstruct validity testing of a virtual reality simulator for transrectalultrasound (TRUS), which allows doctors-in-training to performmultiple different biopsy schemes.Methods: This biopsy system design uses a regular “end-firing”TRUS probe. Movements of the probe are tracked with a micromagneticsensor to dynamically slice through a phantom patient’s3D prostate volume to provide real-time continuous TRUS views.3D TRUS scans during prostate biopsy clinics were recorded.Intrinsic reliability was assessed by comparing the left side of theprostate to the right side of the prostate for each biopsy. A contentand face validity questionnaire was administered to 26 doctors toassess the simulator. Construct validity was assessed by comparingnotes from experts and novices with regards to the time taken andthe accuracy of each biopsy.Results: Imaging data from 50 patients were integrated into thesimulator. The completed VR TRUS simulator uses real patientimages, and is able to provide simulation for 50 cases, with ahaptic interface that uses a standard TRUS probe and biopsy needle.Intrinsic reliability was successfully demonstrated by comparingresults from the left and right sides of the prostate. Face andcontent validity respondents noted the realism of the simulator,and its appropriateness as a teaching model. The simulator wasable to distinguish between experts and novices during constructvalidity testing.Conclusions: A virtual reality TRUS simulator has successfully beencreated. It has promising face, content and construct validity results.

Outcomes of pT0N0 at radical cystectomy: The Canadian Bladder

Collapse

Regional differences in practice patterns and associated outcomes for upper tract urothelial carcinoma in Canada

INTRODUCTION

: We delineated Canadian regional differences in practice patterns in the management of upper tract urothelial carcinoma (UTUC) after nephroureterectomy and relate these to patient outcomes.

METHODS

: A database was created with 1029 patients undergoing radical nephroureterectomy for UTUC between 1994 and 2009 at 10 Canadian centres. Demographic, clinical and pathological variables were collected from chart review. Practice pattern variables were defined as: open versus laparoscopic nephroureterectomy, management strategy for the distal ureter, performance of lymphadenectomy and administration of chemotherapy and/or radiation therapy. The outcome measures were overall (OS), disease-specific (DSS) and recurrence-free survival (RFS). The centres were divided into three regions (West, Central, East). Cox proportional multivariable linear regression analysis was used to determine the association between regional differences in practice patterns and clinical outcomes.

RESULTS

: There was a significant difference in practice patterns between regions within Canada for: time from diagnosis to surgery (p = 0.001), type of surgery (open vs. laparoscopic, p < 0.01) and method of management of the distal ureter (p = 0.001). As well, there were significant differences in survival between regions across Canada: 5-year OS (West 70%, Central 81% and East 62%, p < 0.0001) and DSS (West=79%, Central=85%, East=75%, p = 0.007) were significantly different, but there was no difference in RFS (West 47%, Central 48%, East 46%, p = 0.88). Multivariable linear regression analysis demonstrated that the differences in survival were independent of region OS (p = 0.78), DSS (p = 0.30) or RFS (p = 0.43).

CONCLUSION

: There is significant disparity in practice patterns between regions within Canada, but these do not appear to have an effect on survival. We believe that the variability in practice is a reflection of the lack of standardized treatments for UTUC and underlines the need for multi-institutional studies in this disease.

Natural history of pT3-4 or node positive bladder cancer treated with radical cystectomy and no neoadjuvant chemotherapy in a contemporary North-American multi-institutional cohort

BACKGROUND

The present study documents the natural history and outcomes of high-risk bladder cancer after radical cystectomy (RC) in patients who did not receive neoadjuvant chemotherapy during a contemporary time period.

METHODS

We analyzed 1180 patients from 1993 to 2008 with >pT3N0 or pT0-4N+ bladder cancer who underwent RC ± standard (sLND) or extended (eLND) lymph node dissection from 8 Canadian centres.

RESULTS

Of the 1180 patients, 55% (n = 643) underwent sLND, 34% (n = 402) underwent ePLND and 11% did not undergo a formal LND. Of the total number of patients, 321 (27%) received adjuvant chemotherapy. The median follow-up was 2.1 years (range: 0.6 to 12.9). Overall 30-day mortality was 3.2%. Clinical and pathological stages T3-4 were present in 6.1% and 86.7% of the patients, respectively; this demonstrates a dramatic understaging. Overall survival (OS) at 2 and 5 years was 60% and 43%, respectively. Patients who received adjuvant chemotherapy had a 2- and 5-year disease-specific survival (DSS) of 72% and 57% versus 64% and 51% for those who did not (log-rank p = 0.0039). The 2- and 5-year OS for high-risk node-negative disease was 67% and 52%, respectively, whereas for node-positive patients, the OS was 52% and 32%, respectively (p < 0.001). The OS, DSS and RFS for patients with pN0 were significantly improved compared to those who did not undergo a LND (log-rank p = 0.0035, 0.0241 and 0.0383, respectively).

INTERPRETATION

This series suggests that bladder cancer outcomes in advanced disease have improved in the modern era. The need for improved staging investigations, use of neoadjuvant chemotherapy and performance of complete LND is emphasized.

Management of skeletal-related events in patients with advanced prostate cancer and bone metastases: Incorporating new agents into clinical practice

Skeletal-related events (SREs) are a common complication of bone metastases, and have serious negative consequences for patients with castrate-resistant prostate cancer (CRPC). SREs can lead to severe pain, increased risk of death, increased health care costs and reduced quality of life. Until recently, zoledronic acid has been the sole standard of care for the prevention of SREs in men with CRPC with bone metastases. Denosumab, a receptor activator of nuclear factor kappa-B ligand (RANK-L) inhibitor, has been recently approved for use in Canada for this indication, thus presenting another option for these patients. Denosumab was shown to be superior to zoledronic acid in delaying the time to first or subsequent SREs in CRPC patients with bone metastases. This review discusses current and previous trials examining agents designed to prevent SREs in men with CRPC and bone metastases. It also discusses the practical aspects of administering a bone-targeted therapy, including choosing a bone-targeted therapy, monitoring at the onset and during therapy, switching from one therapy to another, and assessing potential complications.

Canadian Consensus Conference: The FDA decision on the use of 5ARIs

Collapse

Natural history of pT3-4 or node positive bladder cancer treated with radical cystectomy and no neoadjuvant chemotherapy in a contemporary North-American multi-institutional cohort

Background: The present study documents the natural history and outcomes of high-risk bladder cancer after radical cystectomy (RC) in patients who did not receive neoadjuvant chemotherapy during a contemporary time period.Methods: We analyzed 1180 patients from 1993 to 2008 with >pT3N0 or pT0-4N+ bladder cancer who underwent RC ± standard (sLND) or extended (eLND) lymph node dissection from 8 Canadian centres.Results: Of the 1180 patients, 55% (n = 643) underwent sLND, 34% (n = 402) underwent ePLND and 11% did not undergo a formal LND. Of the total number of patients, 321 (27%) received adjuvant chemotherapy. The median follow-up was 2.1 years (range: 0.6 to 12.9). Overall 30-day mortality was 3.2%. Clinical and pathological stages T3-4 were present in 6.1% and 86.7% of the patients, respectively; this demonstrates a dramatic understaging. Overall survival (OS) at 2 and 5 years was 60% and 43%, respectively. Patients who received adjuvant chemotherapy hada 2- and 5-year disease-specific survival (DSS) of 72% and 57% versus 64% and 51% for those who did not (log-rank p = 0.0039). The 2- and 5-year OS for high-risk node-negative disease was 67%and 52%, respectively, whereas for node-positive patients, the OS was 52% and 32%, respectively (p < 0.001). The OS, DSS and RFS for patients with pN0 were significantly improved compared to those who did not undergo a LND (log-rank p = 0.0035, 0.0241 and 0.0383, respectively).Interpretation: This series suggests that bladder cancer outcomes inadvanced disease have improved in the modern era. The need for improved staging investigations, use of neoadjuvant chemotherapyand performance of complete LND is emphasized.

Management of skeletal-related events in patients with advanced prostate cancer and bone metastases: Incorporating new agents into clinical practice

Skeletal-related events (SREs) are a common complication of bone metastases, and have serious negative consequences for patients with castrate-resistant prostate cancer (CRPC). SREs can lead to severe pain, increased risk of death, increased health care costs and reduced quality of life. Until recently, zoledronic acid has been the sole standard of care for the prevention of SREs in men with CRPC with bone metastases. Denosumab, a receptor activator of nuclear factor kappa-B ligand (RANK-L) inhibitor, has been recently approved for use in Canada for this indication, thus presenting another option for these patients. Denosumab was shown to be superior to zoledronic acid in delaying the time to first or subsequent SREs in CRPC patients with bone metastases. This review discusses current and previous trials examining agents designed to prevent SREs in men with CRPC and bone metastases. It also discusses the practical aspects of administering a bone-targeted therapy, including choosing a bone-targeted therapy, monitoring at the onset and during therapy, switching from one therapy to another, and assessing potential complications.

Regional differences in practice patterns and associated outcomes for upper tract urothelial carcinoma in Canada

Introduction: We delineated Canadian regional differences in practice patterns in the management of upper tract urothelial carcinoma (UTUC) after nephroureterectomy and relate these to patient outcomes.Methods: A database was created with 1029 patients undergoing radical nephroureterectomy for UTUC between 1994 and 2009 at 10 Canadian centres. Demographic, clinical and pathological variables were collected from chart review. Practice pattern variables were defined as: open versus laparoscopic nephroureterectomy, management strategy for the distal ureter, performance of lymphadenectomy and administration of chemotherapy and/or radiation therapy. The outcome measures were overall (OS), disease-specific (DSS) and recurrence-free survival (RFS). The centres were divided into three regions (West, Central, East). Cox proportional multivariable linear regression analysis was used to determine the association between regional differences in practice patterns and clinical outcomes.Results: There was a significant difference in practice patterns between regions within Canada for: time from diagnosis to surgery (p = 0.001), type of surgery (open vs. laparoscopic, p < 0.01) and method of management of the distal ureter (p = 0.001). As well, there were significant differences in survival between regions across Canada: 5-year OS (West 70%, Central 81% and East 62%, p < 0.0001) and DSS (West=79%, Central=85%, East=75%, p = 0.007) were significantly different, but there was no difference in RFS (West 47%, Central 48%, East 46%, p = 0.88). Multivariable linear regression analysis demonstrated that the differences in survival were independent of region OS (p = 0.78), DSS (p = 0.30) or RFS (p = 0.43).Conclusion: There is significant disparity in practice patterns between regions within Canada, but these do not appear to have an effect on survival. We believe that the variability in practice is a reflection of the lack of standardized treatments for UTUC and underlines the need for multi-institutional studies in this disease.

Comparison of oncological outcomes for open and laparoscopic radical nephroureterectomy: results from the Canadian Upper Tract Collaboration

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?Open radical nephroureterectomy (ORNU) with excision of the ipsilateral bladder cuff is a standard treatment for upper tract urothelial carcinoma (UTUC). However, over the past decade laparoscopic RNU (LRNU) has emerged as a minimally invasive surgical alternative. Data comparing the oncological efficacy of ORNU and LRNU have reported mixed results and the equivalence of these surgical techniques have not yet been established. We found that surgical approach was not independently associated with overall or disease-specific survival; however, there was a trend toward an independent association between LRNU and poorer recurrence-free survival (RFS). To our knowledge, this is the first large, multi-institutional analysis to show a trend toward inferior RFS in patients with UTUC treated with LRNU.

OBJECTIVE

To examine the association between surgical approach for radical nephroureterectomy (RNU) and clinical outcomes in a large, multi-institutional cohort, as there are limited data comparing the oncological efficacy of open RNU (ORNU) and laparoscopic RNU (LRNU) for upper urinary tract urothelial carcinoma (UTUC).

PATIENTS AND METHODS

Institutional RNU databases containing detailed information on patients with UTUC treated between 1994 and 2009 were obtained from 10 academic centres in Canada. Data were collected on 1029 patients and combined into a relational database formatted with patient characteristics, pathological characteristics, and survival status. Surgical approach was classified as ORNU (n = 403) or LRNU (n = 446). The clinical outcomes were overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS). The Kaplan-Meier method and Cox proportional regression analysis were used to analyse survival data.

RESULTS

Data were evaluable for 849 of 1029 (82.5%) patients. The median (interquartile range) follow-up duration was 2.2 (0.6-5.0) years. The predicted 5-year OS (67% vs 68%, log-rank P = 0.19) and DSS (73% vs 76%, log-rank P = 0.32) rates did not differ between the ORNU and LRNU groups; however, there was a trend toward an improved predicted 5-year RFS rate in the ORNU group (43% vs 33%, log-rank P = 0.06). Multivariable Cox proportional regression analysis showed that surgical approach was not significantly associated with OS (hazard ratio [HR] 0.89, 95% confidence interval [CI] 0.63-1.27, P = 0.52) or DSS (HR 0.90, 95% CI 0.60-1.37, P = 0.64); however, there was a trend toward an independent association between surgical approach and RFS (HR 1.24, 95% CI 0.98-1.57, P = 0.08).

CONCLUSION

Surgical approach was not independently associated with OS or DSS but there was a trend toward an independent association between LRNU and poorer RFS. Further prospective evaluation is needed.

The optimization of ELISA for methamphetamine determination: the effect of immunogen, tracer and antibody purification method on the sensitivity

To obtain more sensitive immunoassay for methamphetamine (MA) determination, the optimum condition of enzyme-linked immunosorbent assay (ELISA) was investigated in regard to immunogens, antibody purification methods and coating tracers. Activated MA, N-(4-aminobutyl)methamphetamine (4-ABMA), was conjugated with bovine serum albumin (BSA) or keyhole limpet hemocyanin (KLH) and used as immunogen. The antibodies were purified by protein G chromatography or various immunoaffinity chromatography-linked MA-protein ligands, such as MA-BSA, MA-KLH or MA-ovalbumin (OVA). Each purified antibody was characterized by means of sensitivity and cross-reactivity using the three MA-protein coating tracers, MA-BSA, MA-KLH and MA-OVA. The best sensitivity of each antibody was acquired with the MA-OVA tracer although the tracer concentration and the antibody titer level at optimum condition were varied. The antibody with high titer level did not always yield good sensitivity. At optimum condition, immunoaffinity chromatography-purified antibodies were better for sensitivity and for specificity than protein G-purified antibodies. The cross-reactivity of the purified antibodies seemed to be affected by immunogen structure and showed somewhat different patterns according to the immunoaffinity ligand utilized. These data show that the antibody purification method as well as choice of coating tracer and immunogen is essential for the sensitivity and specificity of EIA; the optimum condition for assay should be discovered using various methods and combinations.