ABSTRACT
Microscopic foci of tumor cells present in distant organs that are imperceptible by available diagnostic techniques counter attempts to eradicate tumors at their site of origin. It is apparent that the ability of neoplastic cells to metastasize represents, together with uncontrolled proliferation, a fundamental feature of malignancy, and attempts to control cancer that ignore the metastatic properties of tumor cells may meet with limited success. Evidence obtained from certain tumor systems in experimental animals indicates that inhibition of host coagulation reactions by means of anticoagulant or antiplatelet drugs forestalls tumor dissemination. A similar interaction may exist for human malignancy, but prospective randomized, clinical trials of antithrombotic drugs have only recently been initiated. Most intriguing are a number of clinical studies that have provided evidence suggestive of a beneficial effect of coagulation inhibitors in cancer. In conclusion, neoplastic cells in certain human tumor types appear to initiate coagulation reactions ordinarily reserved for hemostasis and wound healing.
