R de Crevoisier1, K Slimane2, T Messai3, P Wibault3, F Eschwege3, A Bossi3, S Koscielny4, A Bridier3, C Massard2, K Fizazi2. 1. Department of Radiation, Institut Gustave-Roussy, Villejuif; Departement de Radiotherapie, Centre Eugène Marquis, Avenue Bataille Flandre Dunkerque, Rennes; Departments of. Electronic address: brdecrevoisier2000@yahoo.fr. 2. Department of Medicine. 3. Department of Radiation, Institut Gustave-Roussy, Villejuif. 4. Department of Biostatistics and Epidemiology, Institut Gustave-Roussy, Villejuif, France.
Abstract
BACKGROUND: The aim was to identify predictors of outcome in patients with localized prostate cancer treated with external beam radiotherapy (EBRT), with or without androgen deprivation therapy (ADT). MATERIALS AND METHODS: A total of 448 patients with prostate cancer received EBRT alone (n = 361, group 1) or ADT followed by EBRT (n = 87, group 2). In group 2, ADT was initiated 3 months before EBRT. After baseline prostate-specific antigen (PSA) determination (PSA(preRT)), PSA was assessed during the 6th week of the EBRT course (PSA(6wRT)) in group 1. In group 2, PSA was measured again 3 months after the start of ADT, before EBRT (PSA(ADT-preRT)). RESULTS: In group 1, median PSA(6wRT)/PSA(preRT) was 0.72 and median prostate-specific antigen velocity (PSAV) was -1.5 ng/ml/month. In the multivariate analysis, prognostic groups and PSA(6wRT)/PSA(preRT) (or PSAV) independently predicted biochemical failure (BF), clinical failure (CF), and prostate cancer-specific survival. In group 2, the median PSA(ADT-preRT) was 1.3 ng/ml. In the high-risk group, an undetectable PSA(ADT-preRT) (< or =0.2 ng/ml) predicted BF (P < 0.01) and CF (P = 0.007). CONCLUSION: A PSA decline 6 weeks after the start of EBRT when used as monotherapy and 3 months after the start of ADT in patients treated with combined ADT and EBRT is predictive of progression and specific survival.
BACKGROUND: The aim was to identify predictors of outcome in patients with localized prostate cancer treated with external beam radiotherapy (EBRT), with or without androgen deprivation therapy (ADT). MATERIALS AND METHODS: A total of 448 patients with prostate cancer received EBRT alone (n = 361, group 1) or ADT followed by EBRT (n = 87, group 2). In group 2, ADT was initiated 3 months before EBRT. After baseline prostate-specific antigen (PSA) determination (PSA(preRT)), PSA was assessed during the 6th week of the EBRT course (PSA(6wRT)) in group 1. In group 2, PSA was measured again 3 months after the start of ADT, before EBRT (PSA(ADT-preRT)). RESULTS: In group 1, median PSA(6wRT)/PSA(preRT) was 0.72 and median prostate-specific antigen velocity (PSAV) was -1.5 ng/ml/month. In the multivariate analysis, prognostic groups and PSA(6wRT)/PSA(preRT) (or PSAV) independently predicted biochemical failure (BF), clinical failure (CF), and prostate cancer-specific survival. In group 2, the median PSA(ADT-preRT) was 1.3 ng/ml. In the high-risk group, an undetectable PSA(ADT-preRT) (< or =0.2 ng/ml) predicted BF (P < 0.01) and CF (P = 0.007). CONCLUSION: A PSA decline 6 weeks after the start of EBRT when used as monotherapy and 3 months after the start of ADT in patients treated with combined ADT and EBRT is predictive of progression and specific survival.
Authors: Antonio Finelli; Tomasz M Beer; Simon Chowdhury; Christopher P Evans; Karim Fizazi; Celestia S Higano; Janet Kim; Lisa Martin; Fred Saad; Olli Saarela Journal: JAMA Netw Open Date: 2021-06-01