Almost all advanced cancers could be found early by intense screening of at-risk patients, according to researchers from New York and Malmo, Sweden who analyzed samples taken from a population-based cohort of 21,277 men in Malmo, Sweden between 1974 and 1986 to determine whether initial PSA plasma levels correlated with future diagnosis of advanced disease.
Of the 21,277 cases, 498 men actually developed prostate cancer, and 161 suffered from advanced disease (greater than T3 or metastasis).
Association between PSA levels and eventual development advanced disease was determined using conditional logistical regression. In men with a total PSA of .5, .75, 1., 1.5 and 2 ng/ml, the probability of being diagnosed with advanced disease by age 75 was 2 percent, 3 percent, 4 percent, 7 percent and 12 percent, respectively. Risk was highly concentrated, with 89 percent of advanced cancers occuring in men with the top 10 percent of PSA levels.