Transient elevations in PSA values after prostate cancer radiotherapy—known as PSA bounce—may be the result of late damage to healthy prostatic tissue, researchers reported at the Canadian Urological Association annual meeting in St. John’s, Newfoundland.
Their hypothesis is supported by study findings showing that clinical factors indicative of a lower tumor burden predict PSA bounce, they concluded.
Daniel Taussky, MD, and colleagues at Centre hospitalier de l’Université de Montréal studied 362 patients who received radiotherapy for low-risk PCa and who had a minimum follow-up of 36 months. Of the 362 patients, 58 received standard external beam radiotherapy (EBRT), 74 received hypofractionated EBRT, and 230 received brachytherapy. The researchers defined PSA bounce as a PSA rise of 0.2 ng/mL or greater with subsequent return to baseline within the first 3 years of treatment.
Results showed that 28.5% of the subjects experienced PSA bounce, with no significant difference in PSA bounce rate among the treatment groups. Fewer positive biopsy cores and lower Cancer of the Prostate Risk Assessment (CAPRA) scores were associated with a greater likelihood of PSA bounce. These factors also predicted a shorter time to PSA bounce.