Experience with Postoperative Combined Hormone-Radiation Therapy Using Moderate Hypofractionation for Recurrent Prostate Cancer

Introduction: Postoperative radiotherapy (RT), including adjuvant (ART) and salvage (SRT), widely used for treatment for prostate cancer (PCa) after radical prostatectomy (RP). The low α/β ratio of PCa provides a rationale for dose hypofractionation; however, data on its efficacy and safety in the postoperative setting are limited.
Purpose: To evaluate the efficacy and safety of combined hormone-radiotherapy using a moderately hypofractionated dose regimen to the prostate bed (PB) and pelvic lymph nodes (PLN) with a sequential boost to the PB in PCa patients.
Materials and methods: A retrospective analysis of 64 patients who received postoperative RT combined with androgen deprivation therapy (ADT) between 2020 and 2023 was performed. RT was delivered in two phases: irradiation of the PB and PLN (fraction dose 3 Gy, total dose 39 Gy, 13 fractions) followed by a boost to the PB (fraction dose 3 Gy, total dose 18 Gy, 6 fractions). Biochemical control, radiation toxicity, and quality of life dynamics were assessed.
Results: The median follow-up was 36.5 months. Biochemical recurrence was observed in 17.2 % of patients. Acute grade III genitourinary (GU) toxicity occurred in 4.7 % of patients, while gastrointestinal (GI) toxicity of this grade was absent. Late grade III GU toxicity(urethral strictures, macrohematuria) was recorded in 4.7 % of patients; grade III GI toxicity was not registered. Despite baseline urinary incontinence in 57.8 % of patients, the level of quality of life remained stable throughout the observation period.
Conclusion: Postoperative combined hormone-radiotherapy for PCa using a moderately hypofractionated dose regimen demonstrates high efficacy and a favorable safety profile while preserving quality of life.

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