A case–control study involved 22 patients with active acromegaly and 22 matched healthy controls showed that fibrinogen, antithrombin III, tissue plasminogen inhibitor 1, and plasminogen activator inhibitor 1 (PAI-1) were increased, while protein S and plasma tissue factor pathway inhibitor were reduced in active acromegaly patients compared with controls [59]. This evidence concerns the gene TFPI and acromegaly.