Management of low risk prostate cancer: active surveillance and focal therapy

To summarize the current understanding of the natural history and molecular biology of low-risk prostate cancer, and review the indications for surveillance and focal therapy.

Low-risk prostate cancer, diagnosed in 40-50% of newly diagnosed men in a screened population, represents overdiagnosis in most cases. Gleason pattern 3 cells typically lack the molecular machinery and the genetic abnormalities, which characterize true cancers, with two important caveats. Thirty percent of patients diagnosed with low-risk prostate based on a systematic biopsy cancer harbor higher-grade cancer that is unrepresented on the biopsy. Secondly, a very small minority harbor prehistologic molecular alterations that result in progression to more aggressive disease. Favorable-risk prostate cancer is better viewed as one of multiple risk factors for the presence of higher-grade prostate cancer, and should be managed with close follow-up. Radical intervention should be reserved for clear evidence of more aggressive disease. Focal therapy should be offered to men with higher-risk disease either at baseline, as an alternative to whole gland radiation or surgery or when active surveillance 'fails' (the patient transitions from low risk to higher risk). The two strategies should be seen as complimentary elements of care that can be applied in a risk-stratified manner - taking account of patient preference - from the outset or in sequence

Active surveillance is appropriate for most men with low-risk prostate cancer, and focal therapy may complement active surveillance for those men wishing to continue a tissue-preserving strategy.