Background: A positive influence of anticoagulant treatment in small cell lung cancer (SCLC) has been suggested by experimental and clinical data.
Methods: In a multicenter clinical trial, 277 patients with SCLC were randomized either to receive or not to receive subcutaneous heparin injections for 5 weeks at effective doses, which were monitored by blood coagulation tests. All patients received one of the two chemotherapy regimens studied in this trial, for eight courses in the case of patients with complete or partial response, and subsequently were randomized to receive delayed thoracic radiotherapy after these eight courses.
Results: In comparison to the 139 patients who did not receive heparin, the 138 patients who received anticoagulant treatment obtained better complete response rates (37% vs. 23%, P = 0.004), better median survival (317 days vs. 261 days, P = 0.01), and better survival rates at 1, 2, and 3 years (40% vs. 30%, 11% vs. 9% and 9% vs. 6%, respectively). At subgroups analysis, the results on survival were obtained for limited forms (P = 0.03) but not for extensive diseases (P = 0.31). No important bleeding or thrombocytopenia was related to heparin treatment.
Conclusions: These results confirm the value of anticoagulant treatment in SCLC, already suspected for warfarin and now proven for heparin, but the modes of administration and the biologic explanations for this activity still warrant further investigation.