Key clinical point: A PSA value ≥0.09 ng/mL early after radiation therapy (RT) completion is associated with significantly worse prognosis across all clinical outcomes, and an early PSA reduction of ≥95% is associated with reduced risk of biochemical relapse (BR) and distant metastasis (DM).
Major finding: Post-RT PSA reduction of ≥95% relative to the baseline PSA was associated with a significantly lower risk of BR.
Study details: A single-institution review of 2,566 patients with intermediate and high-risk prostate cancer who were treated with definitive RT and neoadjuvant and concurrent ADT from 1990 to 2012 was performed.
Patel MA, et al. Radiother Oncol. 2019 Jun 6;140:34-40. doi: 10.1016/j.radonc.2019.04.003.
Radiation therapy is a potentially curative therapy for some patients with prostate cancer. However, identification of biomarkers to identify those who could benefit from earlier adjuvant treatments has been elusive. Patel et al. describe a study designed to identify predictors of survival after radiation therapy. A PSA > 0.09 ng/mL post-radiation was associated with worse outcomes with respect to biochemical recurrence, distant metastasis, prostate cancer-specific death, and overall survival. One drawback to the study was the extent of short-course androgen deprivation as compared to current standards. However, future validation of this finding could be used in future adjuvant treatment studies. —Mark A. Klein, MD