Among patients newly diagnosed with localized prostate cancer, a large number will have low-risk cancer. The doctor determines this using PSA blood test levels, tumor extent (the size and volume of the tumor as measured by digital rectal examination and/or magnetic resonance imaging [MRI]), and microscopic tumor appearance on biopsy (tumor grade; as described using the Gleason score). While treatments such as surgery or radiotherapy are recommended for many men with prostate cancer, a non-interventional treatment approach called active surveillance may be more appropriate for most men with low-risk prostate cancer.
To be a candidate for active surveillance, men must first have a prostate biopsy to diagnose prostate cancer (low grade, low volume). Men with an elevated PSA who do not have a prostate biopsy (or have had a negative prostate biopsy – no cancer) are on “PSA surveillance,” rather than active surveillance (for prostate cancer).
Active surveillance is based on the fact that only a small number of men diagnosed with low-risk prostate cancer will have their disease cause symptomatic problems by growing to cause urinary issues or by spreading outside the prostate (metastasizing). Prostate cancer treatments, including surgery and radiotherapy, are associated with risks and complications. These include urine leakage (incontinence), impotence (erectile dysfunction), difficulties urinating, and bowel problems. As a result, avoiding (or delaying) treatment may provide a benefit to a patient’s quality of life as long as it doesn’t lead to worse cancer outcomes.
Beginning in 1995, Dr. Laurence Klotz from the University of Toronto and others devised a method to systematically monitor patients. Their intention was to wait to start treating a patient with a plan to cure their prostate cancer. They would begin this treatment if there were any changes indicating that the cancer was more aggressive over time. This became known as active surveillance. It included repeated PSA blood testing, physical examination with digital rectal examination, and repeated prostate biopsy.
Prostate biopsies were repeated for a number of reasons. First, because prostate biopsy is performed as a sample of the prostate, the first repeat (“confirmatory”) biopsy is important to make sure that more aggressive cancer wasn’t missed on the first biopsy. After the repeat biopsy, ongoing biopsies are performed every few years. They are also performed at any point when changes in the physical exam or PSA test results warrant.
Twenty years after first starting this program, Dr. Klotz published results showing that active surveillance was very safe: while 149 of 993 patients had died, 134 of these were from reasons other than prostate cancer and only 15 patients died of prostate cancer. Even more impressively, only 267 (27%) of patients switched from active surveillance to needing treatment. Thus, the majority of men who were followed using this approach needed no treatment, and their cancer did not get worse after 15 years.
Many other groups, including Johns Hopkins Medical Institute, the Royal Marsden Hospital in London, the University of California San Francisco, the Princess Margaret Cancer Centre in Toronto, Memorial Sloan Kettering Cancer Center in New York, the Prostate Cancer Research International Active Surveillance (PRIAS), and the University of Miami have studied this approach, using slightly different rules to determine which patients would be eligible for active surveillance. Each has shown that this is a safe and effective treatment approach.
As a result of these studies, the American Society for Clinical Oncology (ASCO) recommends active surveillance as the “best available care option” for patients with very-low risk prostate cancer and the “preferable care option” for most patients with low-risk prostate cancer. Recent studies have shown that active surveillance is being used more and more in the United States. However, it is used much more commonly in other countries such as Canada, Sweden, the United Kingdom, and others.
MRI now has become much more commonly used for prostate cancer patients, including those considering active surveillance. This has given increased precision to the active surveillance approach. Today, patients treated on active surveillance are likely to have periodic physical examinations, PSA blood tests, MRIs, and prostate biopsies.