Family history in the Finnish Prostate Cancer Screening Trial

Family history (FH) is one of the few known risk factors for prostate cancer (PC). There is also new evidence about mortality reduction in screening of PC with prostate-specific antigen (PSA). Therefore, we conducted a prospective study in the Finnish Prostate Cancer Screening Trial to evaluate the impact of FH on outcomes of PC screening. Of the 80,144 men enrolled, 31,866 men were randomized to the screening arm and were invited for screening with PSA test (cut-off 4 ng/ml) every 4 years. At the time of each invitation, FH of PC (FH) was assessed through a questionnaire. The analysis covered a follow-up of 12 years from randomization for all men with data on FH. Of the 23,702 (74.3%) invited men attending screening, 22,756 (96.0%) provided information of their FH. Altogether 1,723 (7.3%) men reported at least one first-degree relative diagnosed with PC and of them 235 (13.6%) were diagnosed with PC. Men with a first-degree FH had increased risk for PC (risk ratio (RR) 1.31, p<0.001) and the risk was especially elevated for interval cancer (RR 1.65, 95% CI 1.27-2.15). Risk for low-grade (Gleason 2-6) tumors was increased (RR 1.46, 95% CI 1.15-1.69), but it was decreased for Gleason 8-10 tumors (RR 0.48, 95% CI 0.25-0.95). PSA test performance (sensitivity and specificity) was slightly inferior for FH positives. No difference in PC mortality was observed in terms of FH. Our findings provide no support for selective PSA screening targeting men with FH of PC. What's new? Hereditary factors are responsible for as many as 40 percent of early-onset cases of prostate cancer (PC). Targeting men with a family history of early-onset disease through selective prostate-specific antigen (PSA) screening could improve screening outcomes. This study shows, however, that men who have a first-degree relative with PC are more likely to be diagnosed with PC in the period of time between screenings than they are at the time of screening. Frequency of low-grade tumors and lack of difference in mortality between those with or without family history further indicate that selective PSA screening would be ineffective.