Adjuvant/Salvage Radiotherapy Following Prostatectomy

How to cite: Stock RG. “Adjuvant/Salvage Radiotherapy Following Prostatectomy.” October 23, 2025. Accessed Apr 2026. https://grandroundsinurology.com/adjuvant-salvage-radiotherapy-following-prostatectomy-2/

Summary

Richard G. Stock, MD, Professor of Radiation Oncology, Mount Sinai, New York, New York, examines the clinical decision-making framework for adjuvant versus salvage radiotherapy following radical prostatectomy. Dr. Stock reviews the historical rationale for postoperative radiation, emphasizing that radical prostatectomy can leave residual malignant cells in the prostate bed, particularly in the presence of adverse pathologic features.

The discussion outlines key pathologic and clinical risk factors associated with residual disease, including positive surgical margins, extracapsular extension, seminal vesicle invasion, detectable postoperative prostate-specific antigen (PSA), Gleason score, and PSA doubling time. Dr. Stock explains the fundamental trade-off between adjuvant radiotherapy, which treats microscopic disease but risks overtreatment, and salvage radiotherapy, which avoids overtreatment but addresses a larger tumor burden once PSA recurrence is evident.

Retrospective series are reviewed to demonstrate prognostic variables that influence outcomes after salvage radiotherapy. Lower pre-radiotherapy PSA levels, longer PSA doubling times, positive surgical margins, absence of seminal vesicle invasion, and lower Gleason scores are consistently associated with improved biochemical control. Outcomes from large multi-institutional cohorts show that long-term disease control with salvage radiotherapy alone is limited for many patients, particularly those with unfavorable features.

Randomized trials evaluating adjuvant radiotherapy are reviewed, including EORTC and SWOG studies, which demonstrate improvements in biochemical control, local control, and, with longer follow-up, metastasis-free and overall survival. These trials support the concept that local failure is a dominant mode of recurrence after prostatectomy in high-risk patients.

The RADICALS-RT trial is discussed as a pivotal study comparing adjuvant radiotherapy with early salvage radiotherapy triggered by low-level PSA rise. Using defined PSA thresholds, early salvage radiotherapy achieved outcomes comparable to adjuvant treatment while resulting in lower urinary and bowel toxicity.

Dr. Stock emphasizes that close postoperative PSA surveillance, with timely early salvage radiotherapy, represents a reasonable, evidence-based approach when diligent follow-up is ensured.

About the 28th Annual Southwest Prostate Cancer Symposium:

Presented by Program Chairs Nelson N. Stone, MD, Richard G. Stock, MD, and William K. Oh, MD, this conference educated attendees about advances in the management of localized and advanced prostate cancer, with a focus on imaging, technology, and training in the related devices. It included a scientific session, as well as live demonstrations of surgical techniques. You can learn more about the conference here.