Active surveillance for low-risk prostate cancer.

Active surveillance for localized prostate cancer entails initial expectant management rather than immediate therapy, with "curative-intent" treatment deferred until there is evidence that the patient is at increased risk for disease progression. This is a response to the clearly documented risks of over diagnosis and overtreatment of low-risk prostate cancer, which in most cases poses little or no threat to the patient. It is based upon the prolonged natural history of prostate cancer and is an attempt to balance the risks and side effects of overtreatment against the possibility of disease progression and a lost opportunity for cure. Low-risk prostate cancer is more accurately viewed as one of multiple risk factors for the presence of higher grade prostate cancer. Like atypical small acinar proliferation, (ASAP), it may be managed with close follow up but without radical intervention, unless there is clear evidence of more aggressive disease.