Active surveillance appears to be safe through 15 years of follow-up for men who have low-risk prostate cancer, according to a report published online Dec. 15 in the Journal of Clinical Oncology.
In extended follow-up of a prospective cohort study begun in 1995, 993 men (current median age, 68 years; range, 41-89 years) with low-risk prostate cancer were assessed. Active surveillance consisted of PSA testing every 3 months for the first 2 years after diagnosis and then every 6 months thereafter, with repeat biopsy at 1 year and then every 3-4 years until the age of 80. These study participants were offered radical intervention only if the disease showed signs of progression, said Dr. Laurence Klotz of Sunnybrook Health Sciences Centre, University of Toronto, and his associates.
A total of 149 patients died, 819 were alive, and 25 were lost to follow-up. Only 15 men (1.5%) died from prostate cancer, and an additional 13 men with confirmed metastases either are alive (9 patients) or died from other causes (4 patients). Overall, the risk of dying from another cause was nearly 10 times greater than that for dying from prostate cancer (HR, 9.2). Even among men younger than 70, who had lower competing risks of death from other causes than older men, the risk of death from another cause was almost six times greater than that for death from prostate cancer (HR, 5.8), the investigators said (J. Clin. Oncol. 2014 Dec. 15 [doi:10.1200/JCO.2014.55.1192]).
The rate of patients who developed PSA failure during follow-up was 2.8% at 5 years and 10.2% at 10 years after diagnosis. These outcomes are consistent with those in low-risk patients managed with initial definitive intervention such as radiotherapy and surgery, Dr. Klotz and his associates added.
This study was supported by the Prostate Cancer Research Foundation of Canada. Dr. Klotz and his associates reported having no financial conflicts of interest.