Source: Ian M. Thompson Jr, MD
Prostate biopsy pre-test probability calculator based on multiple factors:
Prostate Cancer Prevention Trial Risk Calculator 2.0 (PCPTRC 2.0): http://deb.uthscsa.edu/URORiskCalc/Pages/uroriskcalc.jsp
Calculator only applies to men aged 55 years or older and who have never had a prior diagnosis of prostate cancer.
With reference to a patient with a calculated 1% risk of detecting a high-grade cancer on biopsy:
In a conversation with the first patient, it can be stressed that although there is a 1-in-100 risk that he may have an aggressive prostate cancer for which a biopsy now and early treatment may prevent a future prostate cancer death, there is a 10-in-100 risk that a low-grade tumor would be found, a tumor that is often inconsequential and that even with an active surveillance strategy would involve years of repeated PSA testing, examinations, and repeated prostate biopsies. If the patient opts for treatment instead of surveillance, there is a risk of erectile dysfunction and a risk of urinary adverse effects (incontinence or obstruction). There is also a 4% risk of sepsis with biopsy. In this patient, the risk of detection of a low-grade, potentially inconsequential tumor is 10 times the likelihood of finding a high-grade cancer. In practice, patients empowered with this information often opt to repeat the assessment in 6 to 12 months rather than undergo an immediate prostate biopsy.
Thompson IM, Jr, Leach RJ, Ankerst DP. Focusing PSA Testing on Detection of High-Risk Prostate Cancers by Incorporating Patient Preferences Into Decision Making.JAMA. Published online August 04, 2014. doi:10.1001/jama.2014.9680.
Excellent video from Dr. Thompson disussing prostate cancer, screening and interpretation of calculated risks:
Another excellent video by Dr. Mike Evans: