A family history of prostate cancer is associated with a higher risk for prostate cancer to first-degree relatives. If greater surveillance of men at familial risk is considered to be useful, population-based estimates of the differences in the age at diagnosis between familial and sporadic prostate cancer cases are needed.
The men in the nationwide Swedish Family-Cancer Database were classified according to the number and type of affected first-degree relatives (father or brother) and according to the relative's age at diagnosis. The cumulative incidence of prostate cancer and cumulative prostate cancer-specific mortality were estimated using a stratified Cox model.
The cumulative incidence was highest for men with multiple affected first-degree relatives, and it was higher for brothers than for sons of prostate cancer patients. The age to reach the same cumulative incidence as the general population at age 55 years decreased with decreasing age at diagnosis of the relative, ranging from 48.7 years (father diagnosed before 60 years of age) to 53.7 years (father diagnosed after 82 years of age). Prostate cancer-specific mortality was also related to the number and type of affected relatives but there was no clear evidence for a dependency on the age at diagnosis of the relative.
Men with a father or a brother affected by prostate cancer are diagnosed and die at earlier ages than men without a family history of prostate cancer. This study should encourage further analysis in order to assess the risks and benefits of screening for prostate cancer in men at higher risk.