Patients with slow-growing prostate cancer are increasingly opting for active surveillance and only changing treatment plan if the disease changes to a higher risk form to avoid unnecessary and potentially toxic treatments, according to a report published in the Canadian Medical Association Journal.1
Clinical guidelines published by the US Preventive Services Task Force and the Canadian Task Force on Preventive Health Care recommend against routine screening for serum prostate-specific antigen (PSA), in part due to the risk of overdiagnosis and overtreatment of indolent disease. Low-grade prostate cancer with a Gleason score of 6 or lower is correlated with a small risk of cancer-related death.
This study evaluated whether patients with low-grade prostate cancer managed their disease with active surveillance or immediate treatment.
Researchers examined data from patients referred to the Ottawa Regional Prostate Cancer Assessment Clinic, in Ottawa, Ontario, Canada, with abnormal serum PSA or prostate examination results between April 2008 and January 2013. Data from patients with biopsy-proven, low-grade cancer (n=477) were included.
Overall, active surveillance was used for 210 (44.0%) patients with low-grade prostate cancer. The annual proportion of patients undergoing active surveillance increased from 32% in 2008 to 67% in 2013. Active surveillance was defined as monitoring serum PSA, digital rectal examinations, and repeat biopsies.
In the event of cancer progression, patients received treatment with curative intent. Within a median of 1.3 years, 62 of 210 (29.5%) men under active surveillance received treatment. Most of the patients were treated (n=52; 84%) because they had upgraded disease based on a surveillance biopsy.
Higher Charlson comorbidity index and age older than 70 years both correlated with active surveillance. Palpable tumor, PSA density above 0.2 ng/mL2, and more than 2 positive biopsy cores correlated with immediate treatment. Final pathologic examination revealed that 103 of 173 (59.5%) men who received immediate surgical treatment had higher grade or advanced stage disease.
“Recent data suggest that low-grade prostate cancer can grow very slowly, and therefore many patients likely don’t need treatment at all,” said Rodney Breau, MD, MS, assistant professor of urology and associate scientist, Clinical Epidemiology Program, The Ottawa Hospital and the University of Ottawa, Ontario, Canada, and senior author of the study.
“Some men can go for years, or maybe their entire lives, without the cancer spreading. If we monitor patients closely, we can still treat the cancer if it becomes higher risk. If the cancer doesn’t progress, they can avoid unnecessary surgery, radiation, and other therapies, which can have side effects including incontinence, impotence, and bowel problems.”
1. Cristea O, Lavallée LT, Montroy J, et al. Active surveillance in Canadian men diagnosed with low grade prostate cancer [published online ahead of print February 29, 2016]. Can Med Assoc J. doi:10.1503/cmaj.150832.