Hormone use after radiotherapy failure: a survey of Canadian uro-oncology specialists

Abstract

Introduction: A survey of Canadian uro-oncology specialists was performed to assess practice patterns of patients with recurrent prostate cancer postradiotherapy and to assess the feasibility of conducting a trial in this setting.Methods: There were 14 survey questions and 1 demographic question. Responses were reported by frequency.Results: There were 96 respondents. Most respondents use both prostate-specific antigen doubling time (PSAdt) and PSA level when deciding to start androgen deprivation therapy (ADT) in asymptomatic patients. About half of respondents start ADT when PSA is greater than 10 ng/mL or when the PSAdt is less than 6 months. Eighty-six percent felt that the timing of ADT was an important research question. Over 1500 patients per year were estimated as being available for such a trial. Conclusion:After radiotherapy failure, respondents initiated ADT about half of the time when PSA is less than 10 ng/mL and/or PSAdt is less than 6 months. A clinical trial examining the timing of ADT has strong support and appears to be feasible. Résultats : Quatre-vingt-seize médecins ont participé au sondage. Can UrolLa majorité des répondants se basent sur le temps de doublement de l'APS et les taux d'APS pour décider du moment optimal pour amorcer un traitement antiandrogène chez les patients asymptomatiques. Environ la moitié des répondants entreprennent un traitement antiandrogène lorsque le taux d'APS dépasse 10 ng/mL ou lorsque le temps de doublement de l'APS est inférieur à 6 mois. Quatre-vingt-six pour cent des répondants ont indiqué que le moment optimal pour l'amorce du traitement antiandrogène représentait une importante question de recherche. On estime que plus de 1500 patients par année seraient admissibles à une telle étude. Conclusion :Après l'échec d'une radiothérapie, les répondants entreprennent un traitement antiandrogène dans environ la moitié des cas lorsque l'APS est inférieur à 10 ng/mL et/ou lorsque le temps de doublement de l'APS est inférieur à 6 mois. Un essai clinique portant sur la détermination du moment optimal pour l'amorce du traitement antiandrogène est fortement souhaité et semble faisable.

Identification of Site-specific Recurrence Following Primary Radiation Therapy for Prostate Cancer Using C-11 Choline Positron Emission Tomography/Computed Tomography: A Nomogram for Predicting Extrapelvic Disease

“…As such, efforts to minimize the utilization of ADT and treat salvageable recurrences with definitive therapy are important to consider. While biochemical thresholds have been suggested—such as 3 ng/ml as used in the landmark intermittent ADT trial [13] or 10 ng/ml as identified by Canadian urologists [12]—to identify candidates for initiation of ADT, PSA cutoff points alone fail to localize disease. Specifically, in our cohort, 83 of 149 (56%) patients evaluated at a PSA ≥3 ng/ml had potentially salvageable recurrences localized to the pelvis.…”

“…Assessment of calibration and discrimination are summarized by a calibration plot and c -index, respectively. In order to assess the influence of the predictive model at informing decisions, a decision curve analysis was performed as previously described [11], comparing our model to commonly used PSA thresholds for the initiation of ADT (3 ng/ml and 10 ng/ml) and to PSA considered as a continuous adjustment [12,13]. All analyses were performed using SPSS 22.0 (IBM Corp, New York, NY, USA) or R version 3.2.3 (R-Foundation, Vienna, Austria) with two-sided p -values reported and significance considered at p <0.05.…”