1: Baseline PSA levels predict for future development of lethal prostate cancer
An American study published in the Journal of Clinical Oncology has shown that baseline PSA levels taken in midlife were strongly associated with future risk of lethal prostate cancer (PCa). Researchers measured baseline PSA levels in blood samples, collected between 1982 and 1984, from men then aged 40-59 years. Men were divided into two categories: 234 cases (men who were diagnosed with PCa between 1982 and 1993) and 711 matched controls. During follow up, 60 out of the 234 men (26%) originally diagnosed with PCa died of the disease, whereas 11 out of 711 men (2%) selected as controls also developed lethal PCa.
Across all age groups, men with baseline PSA levels above the age-specific median had increased risk of developing PCa compared to men with PSA levels at or below the median. The ORs were 7.3 (95% CI, 2.4 to 21.8) for 40-49 years, 7.6 (95% CI 3.4-17.2) for 50-54 years and 10.1 (95% CI, 5.2 to 19.6) for 55-59 years. The risk of developing lethal PCa was also strongly associated with baseline PSA levels, with 86% of lethal cases occurring in men with PSA measurements above the median level. These results are consistent with previous research and suggest that there may be limited benefit in re-testing men who have no additional risk factors and a PSA less than 1.0ng/ml at 60 years. While significant, this was a small study and future research will be important to confirm these results. For more information about Prostate Cancer UK's position on PSA testing please see our PSA Consensus Statements.