Assessing individual risk for prostate cancer

Purpose To construct a clinical nomogram instrument to estimate individual risk for having prostate cancer ( PC) for patients undergoing prostate specific antigen ( PSA) screening, using all risk factors known for PC. Patients and Methods We conducted a cross-sectional study of 3,108 men who underwent a prostate biopsy, including a subset of 408 volunteers with normal PSA levels. Factors including age, family history of PC ( FHPC), ethnicity, urinary symptoms, PSA, free: total PSA ratio, and digital rectal examination ( DRE) were incorporated in the model. A nomogram was constructed to assess risk for any and high-grade PC ( Gleason score >= 7). Results Of the 3,108 men, 1,304 ( 42.0%) were found to have PC. Among the 408 men with a normal PSA ( < 4.0 ng/ mL), 99 ( 24.3%) had PC. All risk factors were important predictors for PC by multivariate analysis ( P, .01 to .0001). The area under the curve ( AUC) for the nomogram in predicting cancer, which included age, ethnicity, FHPC, urinary symptoms, free: total PSA ratio, PSA, and DRE, was 0.74 ( 95% CI, 0.71 to 0.81) and 0.77 ( 95% CI, 0.74 to 0.81) for high-grade cancer. This was significantly greater than the AUC that considered using the conventional screening method of PSA and DRE only ( 0.62; 95% CI, 0.58 to 0.66 for any cancer; 0.69; 95% CI, 0.65 to 0.73 for high-grade cancer). From receiver operating characteristic analysis, risk factors including age, ethnicity, FHPC, symptoms, and free: total PSA ratio contributed significantly more predictive information than PSA and DRE. Conclusion In a PC screening program, it is important to consider age, family history of PC, ethnicity, urinary voiding symptoms, and free: total PSA ratio, in addition to PSA and DRE.