Following Eggener’s presentation on the role of surgery, Bossi presented the rationale for radiotherapy in these patients.
He began by discussing what is known about radiotherapy administration in high-risk prostate cancer: 1) a high dose to the prostate is preferable; 2) the coadministration of ADT with radiotherapy improves outcomes compared to radiotherapy alone; 3) the coadministration of ADT with radiotherapy improves outcomes compared to ADT alone.
He then established what he felt was not known about radiotherapy in high-risk prostate cancer: 1) the right dose to the prostate; 2) which radiotherapy approach – brachytherapy vs. external beam radiotherapy vs. both, proton vs. photons; 3) the duration of ADT coadministration; and 4) the role of pelvic radiotherapy; and, in his opinion, 5) the comparison of surgery (+/- postoperative radiotherapy +/- ADT) and radiotherapy plus ADT. In contrast to the RCTs which inform what he deemed known about radiotherapy administration in high-risk prostate cancer, he highlighted that the data for these questions in observational in nature.
He then went on the discuss the same paper from Kishan et al. that Eggener had presented. Highlighting that only 43% of surgically treated patients received postoperative radiotherapy, that patients receiving EBRT received approximately 22mo of ADT and those receiving brachytherapy + EBRT received only 12mo of ADT, he showed lower rates of metastases and prostate cancer death in patients receiving the trimodal approach.
He then focused on stratifying patients with high-risk prostate cancer from whom surgery and radiotherapy may be most suitable. Patients with GS 8-10, cT<=2, and PSA<=20 and those with GS 2-7, cT3-4, AND PSA>20, he deemed most suitable for surgical approaches while others he felt more suitable for radiotherapy.
Finally, he highlighted the role of multimodal therapy with postoperative radiotherapy for patients undergoing surgery.
Presented by: Alberto Bossi
Read the Opposing Viewpoint: Treatment of High-Risk Prostate Cancer - Surgery
Written by: Christopher J.D. Wallis, Urology Resident, University of Toronto @WallisCJD at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA