Genetics of Prostate Cancer (PDQ®): Genetics - Health Professional Information [NCI] - Interventions in Familial Prostate Cancer
Decisions about risk-reducing interventions for patients with an inherited predisposition to prostate cancer, as with any disease, are best guided by randomized controlled clinical trials and knowledge of the underlying natural history of the process. However, existing studies of screening for prostate cancer in high-risk men (men with a positive family history of prostate cancer and African American men) are predominantly based on retrospective case series or retrospective cohort analyses. Because awareness of a positive family history can lead to more frequent work-ups for cancer and result in apparently earlier prostate cancer detection, assessments of disease progression rates and survival after diagnosis are subject to selection, lead time, and length biases. (Refer to the PDQ Cancer Screening Overview summary for more information.) This section focuses on screening and risk reduction of prostate cancer among men predisposed to the disease; data relevant to screening in high-risk men are primarily extracted from studies performed in the general population.
Information is limited about the efficacy of commonly available screening tests such as the digital rectal exam (DRE) and serum prostate-specific antigen (PSA) in men genetically predisposed to developing prostate cancer. Furthermore, comparing the results of studies that have examined the efficacy of screening for prostate cancer is difficult because studies vary with regard to the cut-off values chosen for an elevated PSA test. For a given sensitivity and specificity of a screening test, the positive predictive value (PPV) increases as the underlying prevalence of disease rises. Therefore, it is theoretically possible that the PPV and diagnostic yield will be higher for the DRE and for PSA in men with a genetic predisposition than in average-risk populations.[1,2]
Most retrospective analyses of prostate cancer screening cohorts have reported PPV for PSA, with or without DRE, among high-risk men in the range of 23% to 75%.[2,3,4,5,6] Screening strategies (frequency of PSA measurements or inclusion of DRE) and PSA cutoff for biopsy varied among these studies, which may have influenced this range of PPV. Cancer detection rates among high-risk men have been reported to be in the range of 4.75% to 22%.[2,5,6] Most cancers detected were of intermediate Gleason score (5-7), with Gleason scores of 8 or higher being detected in some high-risk men. Overall, there is limited information about the net benefits and harms of screening men at higher risk of prostate cancer. In addition, there is little evidence to support specific screening approaches in prostate cancer families at high risk. Risks and benefits of routine screening in the general population are discussed in the PDQ Prostate Cancer Screening summary. On the basis of the available data, most professional societies and organizations recommend that high-risk men engage in shared decision-making with their health care providers and develop individualized plans for prostate cancer screening based on their risk factors. A summary of prostate cancer screening recommendations for high-risk men by professional organizations is shown in Table 13.