Adjuvant radiation therapy (RT) after radical prostatectomy for lymph node (LN)-positive prostate cancer is associated with decreased mortality risk compared with early salvage RT, especially among men with 4 or more positive LNs, according to a recent study.
Compared with men who received salvage RT, those who had adjuvant RT had a significant 8% reduction in all-cause mortality (ACM) risk for each additional positive pelvic LN, lead investigator Anthony V. D’Amico, MD, PhD, of Harvard Medical School and Brigham and Women’s Hospital in Boston, and colleagues reported in the Journal of Clinical Oncology. The investigators adjusted for the use, timing, and duration of androgen deprivation therapy.
Among patients with 4 or more positive LNs, adjuvant RT recipients had a significantly lower estimated 7-year adjusted ACM rate compared with the salvage RT group (7.7% vs 23.4%). Among patients with 1 to 3 positive LNs, the estimated 7-year adjusted ACM rates were 14.3% in the adjuvant RT group and 13.9% in the salvage RT group, a difference that was not significant.
In a discussion of the clinical significance of these findings, Dr D’Amico and colleagues advised that “it is important to weigh the potential short- and long-term toxicity of pelvic RT against the possible but modest absolute reduction in the risk of ACM when considering its use in men with a single or a few positive LNs.”
In addition, they noted, the findings provide evidence to support that adjuvant RT in patients with 4 or more positive LNs “has the potential to translate into a reduced risk of ACM.”
The study included 17,913 men with pT2-N1M0 prostate cancer who underwent radical prostatectomy and pelvic LN assessment from March 7, 1995 to October 5, 2017. After a median follow-up of 7.0 years, 986 men (5.5%) died, including 223 (22.6%) from prostate cancer.
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Tilki D, Chen MH, Wu J, Huland H, Graefen M, D’Amico AV. Adjuvant versus early salvage radiation therapy after radical prostatectomy for pN1 prostate cancer and the risk of death. J Clin Oncol. Published online March 15, 2022. doi:10.1200/JCO.21.02800