Tefferi A, Elliott M A, Solberg L A, Silverstein M N
Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA.
Blood Rev. 1997 Mar;11(1):1-7. doi: 10.1016/s0268-960x(97)90001-1.
Among the chronic myeloproliferative disorders, polycythemia vera and essential thrombocythemia are unique because of their association with thrombohemorrhagic manifestations and their relatively indolent clinical course. Patients with essential thrombocythemia may not have a significant shortening of life-expectancy and most may not require specific therapy. However, patients with polycythemia vera have a significant risk of transformation of polycythemia vera into acute leukemia or postpolycythemic myelofibrosis (or both). 'High-risk-for-thrombosis' patients with either polycythemia vera or essential thrombocythemia require specific therapy with a platelet-lowering agent to prevent thrombotic complications. Currently, the standard agent used for this is hydroxyurea. However, its tetratogenic and leukemogenic potential has been of concern. As a result, new platelet-lowering agents are being evaluated in the treatment of polycythemia vera and essential thrombocythemia. Anagrelide and interferon alfa are two such agents and have been shown to be effective in reducing platelet counts in patients with chronic myeloproliferative disorders. The putative mechanism of action of these drugs, their specific activity in polycythemia vera and essential thrombocythemia, side-effect profile, and current indications are discussed herein.
在慢性骨髓增殖性疾病中，真性红细胞增多症和原发性血小板增多症较为独特，因为它们与血栓出血表现相关，且临床病程相对惰性。原发性血小板增多症患者的预期寿命可能不会显著缩短，大多数患者可能不需要特殊治疗。然而，真性红细胞增多症患者有将真性红细胞增多症转化为急性白血病或真性红细胞增多症后骨髓纤维化（或两者皆有）的显著风险。真性红细胞增多症或原发性血小板增多症的“高血栓形成风险”患者需要使用血小板降低剂进行特殊治疗，以预防血栓并发症。目前，用于此目的的标准药物是羟基脲。然而，其致畸和致白血病的潜力一直令人担忧。因此，正在评估新型血小板降低剂用于治疗真性红细胞增多症和原发性血小板增多症。阿那格雷和干扰素α就是这样两种药物，已证明它们在降低慢性骨髓增殖性疾病患者的血小板计数方面有效。本文讨论了这些药物的推定作用机制、它们在真性红细胞增多症和原发性血小板增多症中的具体活性、副作用概况以及当前适应证。
