Validation and reliability of current guidelines for the treatment of essential thrombocythemia under real-world clinical settings in Japan

Current guidelines for essential thrombocythemia (ET) patients recommend different treatment approaches based on thrombosis risk stratification models. However, these recommendations may not be applicable to some patients under real clinical settings. Therefore, we carried out a retrospective real-world validation study. Thrombosis-free survival (TFS) was compared between treatment naïve ET patients receiving different treatment approaches. ET patients were stratified by three representative risk models, the conventional, the International Prognostic Score for thrombosis in ET (IPSET-thrombosis), and revised IPSET-thrombosis. Treatment decisions were largely made by individual physicians, taking into account patient preferences and backgrounds. A total of 179 ET patients were included, and thrombotic events were observed in 26 patients. TFS was significantly longer in high-risk patients of all risk models receiving a combination of cytoreductive therapy (CRT) and antiplatelet therapy (APT) compared to CRT alone. Similar results were seen in intermediate-risk patients stratified by IPSET-thrombosis. In contrast, in very low- and low-risk patients of all risk models, TFS was not affected by addition of CRT, indicating that observation or APT alone is an appropriate treatment approach for these patients. We demonstrate that current guidelines provide optimal treatment approaches for Japanese ET patients under real-world clinical settings.目前针对原发性血小板增多症（essential thrombocythemia, ET）患者的临床诊疗指南，基于血栓风险分层模型推荐了差异化的治疗方案。然而，此类指南推荐在部分真实临床场景中未必完全适用。为此，本研究开展了一项回顾性真实世界验证研究。本研究对比了接受不同治疗方案的初治ET患者的无血栓生存期（thrombosis-free survival, TFS）。研究采用3种代表性风险分层模型对入组ET患者进行分组：传统风险模型、ET血栓国际预后评分系统（International Prognostic Score for thrombosis in ET, IPSET-thrombosis）以及修订版IPSET-thrombosis评分系统。治疗方案的选择主要由主管医师结合患者意愿与基础临床背景综合判定。本研究共纳入179例ET患者，其中26例发生血栓事件。在所有风险模型划分的高危患者亚组中，接受细胞减灭治疗（cytoreductive therapy, CRT）联合抗血小板治疗（antiplatelet therapy, APT）的患者，其无血栓生存期显著长于仅接受CRT治疗的患者。在IPSET-thrombosis模型划分的中危患者亚组中，也观察到了一致的结果。与之相反，在所有风险模型划分的极低危与低危患者亚组中，加用CRT并未对其无血栓生存期产生显著影响，提示对于此类患者，仅采取观察随访或单用APT即为合适的治疗方案。本研究证实，当前的诊疗指南可为真实临床场景中的日本ET患者提供最优治疗选择。