Levine M N
Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
Thromb Haemost. 1997 Jul;78(1):133-6.
The etiology of thrombosis in malignancy is multi-factorial, and mechanisms include release of procoagulants by tumor cells, comorbid predisposing factors in anti-cancer drugs. The most reliable information on the incidence of thromboembolism in patients receiving chemotherapy comes from breast cancer. The rate of thrombosis in women with Stage II breast cancer receiving adjuvant chemotherapy is approximately 5%. The highest risk is in postmenopausal women and the addition of tamoxifen to chemotherapy increases the thrombotic risk over chemotherapy alone. The rate of thrombosis in metastatic breast cancer is likely to be much higher than that in Stage II breast cancer. Cancer patients with central venous catheters, e.g. Hickman, portacath, should receive 1 mg of warfarin daily. A recent trial has demonstrated that low molecular weight heparin can prevent catheter-related clots. There has been only one trial conducted evaluating prophylaxis in ambulatory cancer patients receiving chemotherapy. In this study, very low dose warfarin (INR 1.3-1.9) substantially reduced the risk of venous thromboembolism in breast cancer patients receiving chemotherapy.
恶性肿瘤中血栓形成的病因是多因素的，其机制包括肿瘤细胞释放促凝剂、抗癌药物中的合并易感因素。关于接受化疗患者血栓栓塞发生率的最可靠信息来自乳腺癌。接受辅助化疗的II期乳腺癌女性的血栓形成率约为5%。绝经后女性风险最高，化疗中添加他莫昔芬会使血栓形成风险高于单纯化疗。转移性乳腺癌的血栓形成率可能远高于II期乳腺癌。患有中心静脉导管（如希克曼导管、植入式静脉输液港）的癌症患者，应每日服用1毫克华法林。最近一项试验表明，低分子量肝素可预防与导管相关的血栓。仅进行过一项评估门诊接受化疗的癌症患者预防措施的试验。在这项研究中，极低剂量华法林（国际标准化比值1.3 - 1.9）大幅降低了接受化疗的乳腺癌患者发生静脉血栓栓塞的风险。
