Abstract: The present invention provides methods of treating proliferative disease in a patient (e.g., a mammal such as a human) in need of such treatment, said treatment comprising administering, concurrently or sequentially, an effective amount of (1) an anti-platelet or anti-clotting agent and (2) an anti-neoplastic agent and/or radiation therapy. A second method of treatment comprises administering Plavix, also known as clopidogrel, or SR 25909 to a patient in need of such treatment. An additional method comprises administering an anti-platelet or anti-clotting agent to an individual at risk for developing proliferative disease. The methods of the present invention are particularly useful for the treatment or prevention of various cancers, especially epithelial cancers, e.g., prostate cancer, lung cancer, breast cancer, colorectal cancer, and pancreatic cancer.