Hypercoagulable state induced by cytostatic drugs in stage II breast cancer patients.

An increased incidence of thromboembolic complications occurring in cancer patients during chemotherapy was recently reported. In view of this report, a study in 49 patients receiving adjuvant chemotherapy for Stage II breast cancer was begun in order to determine the effect of antineoplastic drugs on coagulation factors and platelet function. Among the coagulation factors, a significant decrease of thrombin time and partial prothrombin time was observed, whereas platelet function tests were unchanged. This finding suggests a trend towards hypercoagulability induced by chemotherapy. This effect should be considered when chemotherapy is employed in advanced cancer patients at high risk for thrombosis.

Hematologic parameters during treatment with high-dose medroxyprogesterone acetate.

Blood clotting, platelet aggregation, complete blood count and lipid profile were evaluated in 12 postmenopausal patients with advanced breast cancer. Patients under treatment with high-dose MPA were considered not at risk for thomboembolic disease and were given MPA orally, 800 mg/day, for at least 3 months. Laboratory investigations were performed prior to treatment with MPA then once weekly during the first month and every 2 weeks during the following months. PTT, TEG, antithrombin III and platelet adhesiveness underwent statistically significant changes, tending towards hypercoagulability, although, on the average, they did not exceed the upper normal range. The authors conclude that a clinically relevant thrombotic activity cannot be attributed to MPA at the administered oral doses in the absence of additional risk factors.