Low-dose warfarin does not decrease the rate of thrombosis in patients with cervix and vulvo-vaginal cancer treated with chemotherapy, radiation, and erythropoeitin

Abstract

Objectives. We had previously reported an association between the use of recombinant human erythropoietin (rHuEPO) and thrombosis in patients with cervix and vulvo-vaginal cancer treated with chemotherapy and radiation. We hypothesized that low-dose warfarin would be effective prevention for thromboembolic events in this setting. Methods. A retrospective analysis of patients with cervical or vulvo-vaginal carcinoma receiving chemoradiation and rHuEpo was performed. Thirty-two patients received rHuEpo alone, and 24 received warfarin (1–2 mg) and rHuEpo. The primary endpoint was objectively proven symptomatic venous thrombosis. Results. There was no difference in the baseline characteristics (e.g. age, stage, body mass index, mean and peak hemoglobin, WBC and platelet counts, and number of transfusions) between these two groups. The rate of thrombosis also was not statistically different ( P = 0.62). Nine of 24 patients had a symptomatic deep vein thrombosis (DVT) while receiving warfarin compared to 10 of 32 patients not on warfarin. There was no difference between the two groups in the percentage of patients with upper extremity DVT ( P = 0.83) or lower extremity DVT ( P = 0.64). Conclusion. Daily low-dose warfarin did not alter the incidence of symptomatic DVT in patients with cervical or vulvo-vaginal cancer who received rHuEpo in conjunction with chemoradiation.