Prostate-specific antigen, prostate cancer, and disorders of hemostasis

Prostate cancer is the most prevalent malignancy in men and the third leading cause of cancer deaths worldwide. Disorders of hemostasis are commonplace in patients with prostate cancer and include disseminated intravascular coagulation, venous thromboembolism, acute coronary syndrome, and postsurgical bleeding. These hemostatic disorders contribute to the mortality and morbidity of prostate cancer. The leading mechanisms proposed to underlie prostate cancer-related coagulopathies are thought to be a hyperexpression of tissue factor, cancer procoagulant, and platelet-activating factor, which is then accompanied by release of large amounts of both prothrombotic and profibrinolytic substances into the bloodstream. Given the generally accepted notion that prostate-specific antigen (PSA) represents an important biomarker in prostate cancer diagnostics, large population screenings were initiated for early detection of cancer. However, recent clinical and economic drawbacks have been recently raised, including evidence that screening exposes patients to a significant risk of both overdiagnosis and overtreatment. Nevertheless, several lines of evidence suggest that PSA may have tumor-suppressing activities. Despite being a member of the vast kallikrein family, which actively interplays with the coagulation cascade, the role of PSA in the pathogenesis of hemostatic disorders observed in prostate cancer patients remains circumstantial and speculative. However, observations that the levels of this cancer marker tend to correlate positively with those of several markers of thrombin generation, and with postsurgical bleeding as well as with coronary atherosclerosis and negative outcomes of myocardial infarction, raise a new and intriguing scenario regarding the pathophysiological role of this serine protease.