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Research paper thumbnail of Influence of molecular imaging on patient selection for treatment intensification prior to salvage radiation therapy for prostate cancer: a post hoc analysis of the PROPS trial

Cancer Imaging

Background The impact of molecular imaging (MI) on patient management after biochemical recurrenc... more Background The impact of molecular imaging (MI) on patient management after biochemical recurrence (BCR) following radical prostatectomy has been described in many studies. However, it is not known if MI-induced management changes are appropriate. This study aimed to determine if androgen deprivation therapy (ADT) management plan is improved by MI in patients who are candidates for salvage radiation therapy. Methods Data were analyzed from the multicenter prospective PROPS trial evaluating PSMA/Choline PET in patients being considered for salvage radiotherapy (sRT) with BCR after prostatectomy. We compared the pre- and post-MI ADT management plans for each patient and cancer outcomes as predicted by the MSKCC nomogram. A higher percentage of predicted BCR associated with ADT treatment intensification after MI was considered as an improvement in a patient’s management. Results Seventy-three patients with a median PSA of 0.38 ng/mL were included. In bivariate analysis, a positive find...

Research paper thumbnail of Opioids use after uro-oncologic surgeries in time of opioid crisis

Canadian Urological Association Journal, 2022

Introduction: Recent literature emphasizes how over-prescription and lack of guidelines contribut... more Introduction: Recent literature emphasizes how over-prescription and lack of guidelines contribute to wide variation in opioid prescribing practices and opioid-related harms. We conducted a prospective, observational study to evaluate opioid prescriptions among uro-oncologic patients discharged following elective in-patient surgery. Methods: Patients who underwent four surgeries were included: open retropubic radical prostatectomy, robot-assisted radical prostatectomy, laparoscopic radical nephrectomy, and laparoscopic partial nephrectomy. The primary outcome was the dose of opioids used after discharge (in oral morphine equivalents [MEq]). Secondary outcomes included: opioid requirements for 80% of the patients, management of unused opioids, opioid use three months postoperative, opioid prescription refills, and guidance about opioid disposal. Results: Sixty patients were included for analysis. Patients used a mean of 30 MEq (95% confidence interval 17.8–42.2) at home and 80% of th...

Research paper thumbnail of Revised protocol. Optimized transformation, overexpression and purification of S100A10

PROTOCOL FOR: Optimized transformation, overexpression and purification of S100A10

Research paper thumbnail of AB047. Membrane binding of S100A10 protein and AHNAK peptide involved in cell membrane repair

Annals of Eye Science, 2019

Research paper thumbnail of Optimized transformation, overexpression and purification of S100A10

BioTechniques, 2019

As a member of the S100 protein family, S100A10 has already been purified. However, its purity, o... more As a member of the S100 protein family, S100A10 has already been purified. However, its purity, or even yield, have often not been reported in the literature. To facilitate future biophysical experiments with S100A10, we aimed to obtain it at a purity of at least 95% in a reasonably large amount. Here, we report optimized conditions for the transformation, overexpression and purification of the protein. We obtained a purity of 97% and performed stability studies by circular dichroism. Our data confirmed that the S100A10 obtained is suitable for experiments to be performed at room temperature up to several days.

Research paper thumbnail of Influence of molecular imaging on patient selection for treatment intensification prior to salvage radiation therapy for prostate cancer: A post hoc analysis of the PROPS trial

Journal of Clinical Oncology

316 Background: The impact of molecular imaging (MI) on patient management after biochemical recu... more 316 Background: The impact of molecular imaging (MI) on patient management after biochemical recurrence (BCR) following radical prostatectomy has been described in many studies. However, it is not known if MI-induced management changes are appropriate. This study aimed to determine if androgen deprivation therapy (ADT) management plan is improved by MI in patients who are candidates for salvage radiation therapy. Methods: Data were analyzed from the multicenter prospective PROPS trial evaluating PSMA/Choline PET in patients being considered for salvage radiotherapy (sRT) with BCR after prostatectomy. We compared the pre- and post-MI ADT management plans for each patient and cancer outcomes as predicted by the MSKCC nomogram. A higher percentage of predicted BCR associated with ADT treatment intensification after MI was considered as an improvement in a patient’s management. Results: Seventy-three patients with a median PSA of 0.38 ng/mL were included. In bivariate analysis, a positi...

Research paper thumbnail of Interpreting Testosterone and Concomitant Prostate Specific Antigen Values during Androgen Deprivation Therapy for Recurrent Prostate Cancer

Journal of Urology, 2021

Purpose: Measurement of testosterone levels during androgen deprivation therapy (ADT) is broadly ... more Purpose: Measurement of testosterone levels during androgen deprivation therapy (ADT) is broadly recommended, but how therapy should be altered in response to testosterone values during ADT remains controversial. Our objective was therefore to evaluate the relation between testosterone and concomitant prostate specific antigen (PSA) levels during ADT on clinical outcomes. Materials and Methods: Patients from the continuous androgen deprivation arm of the PR.7 trial of intermittent ADT for biochemically recurrent prostate cancer following radiotherapy were included. Statistical analyses evaluated the prognostic importance of testosterone levels during ADT relative to concomitant PSA levels. We similarly evaluated whether the number of testosterone breakthroughs >1.7 nmol/l predicted the time to castrate-resistant prostate cancer (CRPC), cancer specific survival (CSS) or overall survival (OS) with Kaplan-Meier and Cox regression analyses. Results: Overall, the prognostic importance of testosterone on outcomes was eclipsed by the prognostic value of concomitant PSA values. The occurrence of testosterone values >0.7 nmol/l in the first year of therapy was associated with subsequent rises >1.7 nmol/l, but the number of testosterone breakthroughs per patient had no relationship to the risk of CRPC, CSS or OS. A time-dependent adjusted analysis indicated as expected that PSA values were prognostic, but there was no association of relative cumulative testosterone exposure with outcomes. Conclusions: In this large-scale trial with long followup, breakthrough testosterone was unrelated to time to CRPC, CSS or OS. Castrate testosterone values during ADT for recurrent prostate cancer provides prognostic information that must be considered alongside the time since ADT initiation and concomitant PSA values.

Research paper thumbnail of Retrospective analysis on the safety and innocuity of monopolar transurethral resection of prostate as outpatient day-care surgery

number : 554 Retrospective Analysis on the Safety and Innocuity of Monopolar Transurethral Resect... more number : 554 Retrospective Analysis on the Safety and Innocuity of Monopolar Transurethral Resection of Prostate as Outpatient Day-Care Surgery Marie-Pier St-Laurent, MD • Samuel Tremblay, MD Geneviève Nadeau, MD, MSc, FRCSC CHU de Québec-Université Laval, Québec (Qc), Canada Patient characteristics Total (%) Day care surgery (DCS) (%) Post-operative hospitalisation (POH) (%) p-value1 Age (Mean SD) 71.62 (SD: 9.48) 70.12 (SD 9.56) 73.23 (SD 9.16) 0.01 BMI (Mean SD) 27.50 (SD: 4.70) 27.41 (SD: 4.77) 27.59 (SD: 4.63) 0.73 Preop bladder catheter or CIC 49.1 49.7 48.6 American Society of Anaesthesiologists (ASA) score 1 13.9 14.4 13.2 0.05 2 64.5 69.0 59.8 3 21.3 16.6 27.0 Coronary artery disease 22.9 19.8 26.3 0.14 Diabetes 22.1 17.6 26.9 0.03 OSAHS 11.9 11.2 12.6 0.69 Cognitive impairment 7.2 3.7 10.9 0.01 Surgery performed under Aspirin 12.7 12.8 12.6 0.94 A/C discontinued preop 8.5 3.7 13.7 0.01 Regional anaesthesia (spinal) 71.3 71.7 70.9 0.87 Table 1: Patients demographics and maj...

Research paper thumbnail of Influence of molecular imaging on patient selection for treatment intensification prior to salvage radiation therapy for prostate cancer: a post hoc analysis of the PROPS trial

Cancer Imaging

Background The impact of molecular imaging (MI) on patient management after biochemical recurrenc... more Background The impact of molecular imaging (MI) on patient management after biochemical recurrence (BCR) following radical prostatectomy has been described in many studies. However, it is not known if MI-induced management changes are appropriate. This study aimed to determine if androgen deprivation therapy (ADT) management plan is improved by MI in patients who are candidates for salvage radiation therapy. Methods Data were analyzed from the multicenter prospective PROPS trial evaluating PSMA/Choline PET in patients being considered for salvage radiotherapy (sRT) with BCR after prostatectomy. We compared the pre- and post-MI ADT management plans for each patient and cancer outcomes as predicted by the MSKCC nomogram. A higher percentage of predicted BCR associated with ADT treatment intensification after MI was considered as an improvement in a patient’s management. Results Seventy-three patients with a median PSA of 0.38 ng/mL were included. In bivariate analysis, a positive find...

Research paper thumbnail of Opioids use after uro-oncologic surgeries in time of opioid crisis

Canadian Urological Association Journal, 2022

Introduction: Recent literature emphasizes how over-prescription and lack of guidelines contribut... more Introduction: Recent literature emphasizes how over-prescription and lack of guidelines contribute to wide variation in opioid prescribing practices and opioid-related harms. We conducted a prospective, observational study to evaluate opioid prescriptions among uro-oncologic patients discharged following elective in-patient surgery. Methods: Patients who underwent four surgeries were included: open retropubic radical prostatectomy, robot-assisted radical prostatectomy, laparoscopic radical nephrectomy, and laparoscopic partial nephrectomy. The primary outcome was the dose of opioids used after discharge (in oral morphine equivalents [MEq]). Secondary outcomes included: opioid requirements for 80% of the patients, management of unused opioids, opioid use three months postoperative, opioid prescription refills, and guidance about opioid disposal. Results: Sixty patients were included for analysis. Patients used a mean of 30 MEq (95% confidence interval 17.8–42.2) at home and 80% of th...

Research paper thumbnail of Revised protocol. Optimized transformation, overexpression and purification of S100A10

PROTOCOL FOR: Optimized transformation, overexpression and purification of S100A10

Research paper thumbnail of AB047. Membrane binding of S100A10 protein and AHNAK peptide involved in cell membrane repair

Annals of Eye Science, 2019

Research paper thumbnail of Optimized transformation, overexpression and purification of S100A10

BioTechniques, 2019

As a member of the S100 protein family, S100A10 has already been purified. However, its purity, o... more As a member of the S100 protein family, S100A10 has already been purified. However, its purity, or even yield, have often not been reported in the literature. To facilitate future biophysical experiments with S100A10, we aimed to obtain it at a purity of at least 95% in a reasonably large amount. Here, we report optimized conditions for the transformation, overexpression and purification of the protein. We obtained a purity of 97% and performed stability studies by circular dichroism. Our data confirmed that the S100A10 obtained is suitable for experiments to be performed at room temperature up to several days.

Research paper thumbnail of Influence of molecular imaging on patient selection for treatment intensification prior to salvage radiation therapy for prostate cancer: A post hoc analysis of the PROPS trial

Journal of Clinical Oncology

316 Background: The impact of molecular imaging (MI) on patient management after biochemical recu... more 316 Background: The impact of molecular imaging (MI) on patient management after biochemical recurrence (BCR) following radical prostatectomy has been described in many studies. However, it is not known if MI-induced management changes are appropriate. This study aimed to determine if androgen deprivation therapy (ADT) management plan is improved by MI in patients who are candidates for salvage radiation therapy. Methods: Data were analyzed from the multicenter prospective PROPS trial evaluating PSMA/Choline PET in patients being considered for salvage radiotherapy (sRT) with BCR after prostatectomy. We compared the pre- and post-MI ADT management plans for each patient and cancer outcomes as predicted by the MSKCC nomogram. A higher percentage of predicted BCR associated with ADT treatment intensification after MI was considered as an improvement in a patient’s management. Results: Seventy-three patients with a median PSA of 0.38 ng/mL were included. In bivariate analysis, a positi...

Research paper thumbnail of Interpreting Testosterone and Concomitant Prostate Specific Antigen Values during Androgen Deprivation Therapy for Recurrent Prostate Cancer

Journal of Urology, 2021

Purpose: Measurement of testosterone levels during androgen deprivation therapy (ADT) is broadly ... more Purpose: Measurement of testosterone levels during androgen deprivation therapy (ADT) is broadly recommended, but how therapy should be altered in response to testosterone values during ADT remains controversial. Our objective was therefore to evaluate the relation between testosterone and concomitant prostate specific antigen (PSA) levels during ADT on clinical outcomes. Materials and Methods: Patients from the continuous androgen deprivation arm of the PR.7 trial of intermittent ADT for biochemically recurrent prostate cancer following radiotherapy were included. Statistical analyses evaluated the prognostic importance of testosterone levels during ADT relative to concomitant PSA levels. We similarly evaluated whether the number of testosterone breakthroughs >1.7 nmol/l predicted the time to castrate-resistant prostate cancer (CRPC), cancer specific survival (CSS) or overall survival (OS) with Kaplan-Meier and Cox regression analyses. Results: Overall, the prognostic importance of testosterone on outcomes was eclipsed by the prognostic value of concomitant PSA values. The occurrence of testosterone values >0.7 nmol/l in the first year of therapy was associated with subsequent rises >1.7 nmol/l, but the number of testosterone breakthroughs per patient had no relationship to the risk of CRPC, CSS or OS. A time-dependent adjusted analysis indicated as expected that PSA values were prognostic, but there was no association of relative cumulative testosterone exposure with outcomes. Conclusions: In this large-scale trial with long followup, breakthrough testosterone was unrelated to time to CRPC, CSS or OS. Castrate testosterone values during ADT for recurrent prostate cancer provides prognostic information that must be considered alongside the time since ADT initiation and concomitant PSA values.

Research paper thumbnail of Retrospective analysis on the safety and innocuity of monopolar transurethral resection of prostate as outpatient day-care surgery

number : 554 Retrospective Analysis on the Safety and Innocuity of Monopolar Transurethral Resect... more number : 554 Retrospective Analysis on the Safety and Innocuity of Monopolar Transurethral Resection of Prostate as Outpatient Day-Care Surgery Marie-Pier St-Laurent, MD • Samuel Tremblay, MD Geneviève Nadeau, MD, MSc, FRCSC CHU de Québec-Université Laval, Québec (Qc), Canada Patient characteristics Total (%) Day care surgery (DCS) (%) Post-operative hospitalisation (POH) (%) p-value1 Age (Mean SD) 71.62 (SD: 9.48) 70.12 (SD 9.56) 73.23 (SD 9.16) 0.01 BMI (Mean SD) 27.50 (SD: 4.70) 27.41 (SD: 4.77) 27.59 (SD: 4.63) 0.73 Preop bladder catheter or CIC 49.1 49.7 48.6 American Society of Anaesthesiologists (ASA) score 1 13.9 14.4 13.2 0.05 2 64.5 69.0 59.8 3 21.3 16.6 27.0 Coronary artery disease 22.9 19.8 26.3 0.14 Diabetes 22.1 17.6 26.9 0.03 OSAHS 11.9 11.2 12.6 0.69 Cognitive impairment 7.2 3.7 10.9 0.01 Surgery performed under Aspirin 12.7 12.8 12.6 0.94 A/C discontinued preop 8.5 3.7 13.7 0.01 Regional anaesthesia (spinal) 71.3 71.7 70.9 0.87 Table 1: Patients demographics and maj...