Long-term durability of PSA failure-free survival after radiotherapy for localized prostate cancer

• Published in: International journal of radiation oncology, biology, physics Vol. 54; no. 2; pp. 420 - 426
• Main Authors: YOCK, Torunn I, ZIETMAN, Anthony L, SHIPLEY, William U, THAKRAL, Harjot K, COEN, John J
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier 01.10.2002
• Subjects: Aged; Aged, 80 and over; Biological and medical sciences; Disease-Free Survival; Humans; Male; Medical sciences; Middle Aged; Multivariate Analysis; Prostate-Specific Antigen - blood; Prostatic Neoplasms - blood; Prostatic Neoplasms - pathology; Prostatic Neoplasms - radiotherapy; Time Factors
• ISSN: 0360-3016; 1879-355X
• DOI: 10.1016/S0360-3016(02)02957-7

To determine the durability of prostate-specific antigen (PSA) progression-free survival beyond 5 years in patients biochemically free of relapse 5 years after external beam radiotherapy (EBRT). This study identified 328 men treated with EBRT to the prostate who were biochemically (American Society for Therapeutic Radiology and Oncology definition) disease free 5 years after treatment. The median follow-up was 7.4 years. The patients were divided into four groups according to their PSA values 5 years after treatment: PSA <or=0.5, 0.5 to <or=1.0, 1.0 to <or=2.0, and 2.0-4.0 ng/mL. PSA progression-free rates were calculated in each subgroup at 10 years after treatment. Yearly hazard rates of biochemical progression were also calculated for the 5-10 years after treatment. The PSA progression-free survival rate was 87%, 79%, and 67%, respectively, 8, 10, and 13 years after treatment in patients biochemically free of disease 5 years after treatment. The progression-free rates at 10 years after treatment according to the PSA level at 5 years was 92% for PSA <or=0.5 ng/mL; 71% for PSA 0.5 to <or=1.0 ng/mL; 78% for PSA 1.0 to <or=2.0 ng/mL; and 56% for PSA 2.0 to <or=4.0. The lower the PSA level at 5 years, the more durable the probability of maintained biochemical disease-free survival (p <0.0001). The yearly hazard rates of biochemical progression ranged from 3.1% to 6.6% in the 5-10 years after RT. When PSA levels remain low (<2 ng/mL) 5 years after EBRT, the great majority of patients will be biochemically disease free at 10 years. The hazard rates of biochemical progression in the 6-10 years after treatment are low and are comparable to those published for prostatectomy series.