Prostate-specific antigen bounce in patients treated before 60 years old by iodine 125 brachytherapy for prostate cancer is frequent and not a prognostic factor

Abstract

PurposeThe only prognostic factor of prostate-specific antigen (PSA) bounce in prostate cancer found in several studies is young age but has never been specifically studied in this subset of patients for long-term results. Bounce characteristics, histological, clinical, and dosimetric data in young patients were analyzed, as well as their impact on toxicity and survival. Material and MethodsThis retrospective study included patients aged ≤60 years treated with exclusive iodine 125 brachytherapy with low or intermediary prostate adenocarcinoma during 1999–2014. Exclusion criteria were a follow-up of ≤24 months. PSA bounce was defined as a ≥0.2-ng/mL increase above the interval PSA nadir, followed by a decrease to nadir or below. ResultsThis study analyzed 179 patients. Median age was 56 years (46–59 years). The median follow-up was 79 months (54; 123). The bounce incidence was 56.8% (49.6%; 64.2%) at 5 years, inversely proportional to positive/total biopsies ratio (HR 0.98, 95% CI [0.97, 0.99]). Incidence of biochemical failure was 1.2%, 95% CI (0.3%; 4.7%), at 5 years with no difference between the bounce and no-bounce group (HR 0.96, 95% CI [0.25; 3.58]). Bounce is an unfavorable prognostic factor for grade two and three urinary toxicities 6.67 (4.14; 10.76) (p < 0.001). ConclusionsPSA bounce is common in young people after brachytherapy. It should be monitored without starting an inadequate and sometimes invasive relapse checkup or a relapse treatment.