Watching but not treating (active surveillance) low-risk prostate cancer

The authors determined the benefits and pitfalls of active surveillance (AS). The authors concluded that AS may reduce over-treatment in low-risk prostate cancer patients without compromising 10-year prostate cancer survival.

AS is a form of non-treatment used in prostate cancer patients who are low-risk. This means that the cancer is confined to the prostate gland and has minimal to no symptoms or signs of growth. In AS, patients are monitored without receiving treatment. If there are signs of disease progression, active treatment is started. The benefit of AS is to delay the necessity of cancer treatment in patients who do not need or require immediate treatment. The main objective of AS is that the cancer outcomes are the same with AS as they would be after immediate cancer treatment.

The authors aimed to review which prostate cancer patients would be eligble for AS.

Prostate specific antigen (PSA – protein elevated in the blood in the presence of cancer) is an important marker for prostate cancer in patients who chose AS. A PSA of less than 10 ng/mL would be an indicator for AS.

There were no significant differences between surgery and AS in patients with a PSA level of less than 10 ng/mL or patients with low to intermediate risk cancer. The results of this study determined that low-risk patients would not benefit from surgery and justified AS.

Gleason scores are based on a scoring system from 1 to 10 used to determine how the agressiveness of the cancer cells. A score of 6 or less is typically considered very low to low risk (cancer contained within the prostate gland). Less aggressive based on Gleason score would be an indicator for AS.

Biopsies (tissue samples taken from the prostate to test for cancer) are used to to detect the presence of prostate cancer. 10 to 12 samples are the standard approach used to determine whether a patient should undergo AS, where the biopsies must show low levels of cancer activity. MRIs (an imaging technique that uses magnetic fields to image organs) are also used to determine whether any abnormal cells growing near the prostate indicate cancer. 

993 patients were used in an AS study with an average follow-up of 6.4 years. 73% remained on AS treatment-free at 10 years. 55% remained so at 15 years. Cancer-specific survival (patients who did not die from cancer following treatment) was 98.5%, while 2.8% of patients developed cancer spread after an average of 7.3 years. 

The authors concluded that AS may reduce over-treatment in low-risk prostate cancer patients without compromising 10-year prostate cancer survival.