To assess toxicity and patient quality of life after stereotactic body radiotherapy (SBRT) to oligoprogressive disease (OPD) in patients with metastatic castrate-resistant prostate cancer (CRPC) on androgen receptor targeted agents (ARTA).
This phase II trial enrolled patients with metastatic CRPC with ≤ 2 oligoprogressive lesions in bone, lymph node, lung, or prostate. All patients were receiving systemic treatment with abiraterone or enzalutamide at the time of oligoprogression. All patients received SBRT to the OPD site(s) and continued the current ARTA. Patients received 30 Gy in 5 fractions (alternate days) to the OPD site. The primary endpoint of the trial is to assess if SBRT to OPD sites results in progression free survival of >6 months. The primary endpoint for this toxicity analysis is the rate of grade 3 or higher adverse events at any timepoint up to 6 months after SBRT. Secondary endpoints included comparing pre- and post-SBRT patient-related outcomes reported using visual analogue scale scores and EQ-5D health questionnaire.
Forty enrolled patients had at least 6 months of follow-up at the time of analysis. Grade 3 or higher toxicity from any cause recorded using common terminology criteria for adverse events and radiation therapy oncology group was found in 8/40 (20%) of patients, but only 1/40 (2.5%) was deemed possibly related to SBRT. There was no significant difference in mean EQ5D visual analogue scale score from baseline to each timepoint after SBRT (p = 0.449).
In this prospective phase II clinical trial for OPD whilst on ARTA in the CRPC setting, we report low grade ≥ 3 toxicity after SBRT. There is no discernible change in patient-reported quality of life due to SBRT treatment. The final results of progression-free survival and toxicity of SBRT treatment will be reported once further follow-up is complete.
Clinical oncology (Royal College of Radiologists (Great Britain)). 2024 Jun 18 [Epub ahead of print]
P H Patel, S Dreibe, A Reid, C Parker, J Murray, A Pathmanathan, A Tirona, J Guevara, Y-E Suh, J Frew, N Palaniappan, I Syndikus, G Attard, N Tunariu, A C Tree
The Royal Marsden NHS Foundation Trust, London, SM2 5PT, UK. Electronic address: ., The Royal Marsden NHS Foundation Trust, London, SM2 5PT, UK., The Royal Marsden NHS Foundation Trust, London, SM2 5PT, UK; The Institute of Cancer Research, London, SM2 5NG, UK., Newcastle Upon Tyne Hospital NHS Foundation Trust, Newcastle-Upon-Tyne, NE7 7DN, UK., Velindre Cancer Centre, Cardiff, CF14 2TL, UK., The Clatterbridge Cancer Centre NHS Foundation Trust, Wirral, CH63 4JY, UK., University College London Cancer Institue, London, NW1 2BU, UK; University College London Hospital, London, NW1 2BU, UK.