Good tolerance of post-RP radiotherapy ± short-term ADT

Dr Paul Sargos (Institut Bergonié, France) presented the first results of the GETUG-AFU 22 study and won the second prize in the EAU20 Best Abstract Awards Oncology [1].

The multicentre, randomised, phase 2 GETUG-AFU 22 study, compared 6 months of degarelix short-term androgen deprivation therapy (ADT) in combination with radiotherapy and radiotherapy alone as salvage treatment for patients with detectable prostate-specific antigen (PSA) levels after radical prostatectomy (RP). The primary efficacy endpoint was event-free survival, which will be reported later this year. Key secondary endpoints were toxicity (as measured by CTCAE V4.0) and quality of life (QLQ-C30 and QLQ-PR25) results.

Dr Sargos presented the key secondary endpoints in 125 patients with localised prostate cancer, treated by RP, with a PSA level post-RP ≥0.2 ng/mL and ≤2 ng/mL at randomisation and N0 M0 on imaging. Median PSA level was 0.3 ng/mL (0.09-1.82) post-RP and 0.6 ng/mL (0.12-3.65) at randomisation.

With a median follow-up of 38 months, the 2-year toxicity showed no differences in late genitourinary or gastrointestinal toxicity between the 2 arms (P=0.145). No difference was seen between the 2 arms for erectile dysfunction, 2 patients in each arm reported cardiovascular events of grade 3 (in the radiotherapy-alone arm: tight coronary stenosis and femoral arteritis; in the radiotherapy + short-term ADT arm: pulmonary embolism and cardiac arrhythmia). The number of second cancers was not significantly different between the arms.

Quality of life was evaluated at 24 months in 59% of patients in the radiotherapy arm and 77% in the radiotherapy plus short-term ADT arm. At 12 months, QLQ-PR25-related symptoms were significantly higher in the radiotherapy plus short-term ADT arm (P=0.04), but these data normalised by 24 months, when no significant difference in QLQ-C30 or QLQ-PR25 outcomes was reported. This study highlights the good tolerance of post-operative radiotherapy with or without short-term ADT.

1. 1. Sargos P, et al. EAU20 Virtual Congress, 17-26 July 2020, Abstract PT925.