Risk of prostate cancer death following a low PSA level in the PLCO Trial.

Longer-than-annual screening intervals have been suggested to improve the balance of benefits and harms in prostate cancer screening. Many researchers, societies, and guideline committees have suggested that screening intervals could depend on the prostate-specific antigen (PSA) result. We analyzed data from men (N = 33,897) ages 55-74 years with a baseline PSA test in the intervention arm of the Prostate, Lung, Colorectal and Ovarian Cancer Screening trial (United States, 1993-2001). We estimated 5- and 10- year risks of aggressive cancer (Gleason >= 8 and/or stage III/IV) and 15-year risks of prostate cancer-related mortality for men with baseline PSA <= 0.5 ng/mL (N = 4,862), <= 1 ng/mL (N= 15,110), and 1.01-2.5 ng/mL (N= 12,422). A total of 217 men died from prostate cancer through 15 years, although no men with PSA <= 1 ng/mL died from prostate cancer within 5 years [95% confidence interval (CI), 0.00%0.03%]. The 5-year incidence of aggressive disease was low (0.08%; 95% CI, 0.03%-0.12%) for men with PSA <= 1 ng/mL, and higher for men with baseline PSA 1.01-2.5 ng/mL (0.51%; 95% CI, 0.38%-0.74%). No men aged >= 65 years with PSA <= 0.5 ng/mL died from prostate cancer within 15 years (95% CI, 0.00%-0.32%), and their 10-year incidence of aggressive disease was low (0.25%; 95% CI, 0.00%-0.53%). Compared with white men, black men with PSA <= 1 ng/mL had higher 10-year rates of aggressive disease (1.6% vs. 0.4%; P < 0.01). Five-year screening intervals may be appropriate for the 45% of men with PSA <= 1 ng/mL. Men ages >= 65 years with PSA <= 0.5 ng/mL could consider stopping screening. Substantial risk disparities suggest appropriate screening intervals could depend on race/ethnicity.