Long term outcomes between adjuvant radiotherapy and combined radiotherapy with hormonal treatment after radical prostatectomy in high risk prostate cancer
Authors:   Division  of  Urology,  Department  of  Surgery,  Faculty  of  Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Kiatbamrungpunt, Chalermchai , Nualyong Chaiyong ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Srinualnad Sittiporn ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of  Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Leewansangtong Sunai ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Taweemonkongsa Tawatchai ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of  Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Chaiyaprasith Bansithi ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of  Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Choti-kawanich Ekkarin ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of  Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Phinthusophon Kittipong ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of  Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Jitpraphai Siros ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of  Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Ramart Patkawat ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of  Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Suk-ouichai Chalairat ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of  Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand, Woranisarakul Varat ,   Division  of  Urology,  Department  of  Surgery,  Faculty  of  Medicine,  Siriraj  Hospital,  Mahidol  University,  Bangkok, Thailand
Published: June 2021

Objective: To determine the oncological outcome of adjuvant treatment between radiotherapy (RT) alone and combined radiotherapy with androgen deprivation therapy (ADT) in high risk prostate cancer patients after radical prostatectomy (RP). Materials and Methods: All medical records of high risk-prostate cancer patients (including PSA > 20 ng/ml, pT3-pT4 or Gleason score 8-10) who underwent RP in Siriraj Hospital between 2000 and 2016 were retrospectively reviewed. Demo-graphic data, pathological staging, types of adjuvant treatment, time to follow up and time to biochemical recurrence (BCR) were analyzed. Results: Undetectable PSA after RP was achieved in 1009 out of 1221 high risk prostate cancer patients who had been followed up at least 6 months after surgery. Pathological staging pT2, pT3, pT4 and N1 was 23.8%, 73%, 0.8% and 4.7%, respectively. Forty one percent received adjuvant treatment (41 adjuvant RT alone, 74 combined adjuvant RT and ADT, 303 ADT alone). Median follow up time in the adjuvant RT group and combined treatment group was 63.8 months (8.9 - 210.7). BCR rates were 22% (9 of 41) for adjuvant RT and 12.2% (9 of 74) for adjuvant combined treatment. 10-year BCR-free survival in the two groups was 70.2% and 83.8%, respectively. There was no statistical difference between adjuvant RT and adjuvant combined treatment in terms of survival benefit (Hazard Ratio 0.40; p = 0.057). Conclusion: Adjuvant radiotherapy after radical prostatectomy increases long term survival outcomes for high risk prostate cancer patients. This study shows that combined adjuvant RT and ADT may improve BCR-free survival.