不同剂量来曲唑治疗绝经后晚期乳腺癌疗效的系统评价

Systemic evaluation of the curative effect of letrozole for terminal breast cancer in postmenopausal patients

目的评价0.5mg和2.5mg来曲唑治疗绝经后晚期乳腺癌的有效性和安全性。方法计算机检索Cochrane图书馆、PubMed、EMBASE、CBM、CNKI、VIP等数据库,并手工检索相关文献,收集0.5mg与2.5mg来曲唑治疗绝经后晚期乳腺癌的随机对照试验(RCT),所有检索更新至2010年3月。根据Cochrane评价手册5.0.0对纳入研究进行方法学质量评价并采用RevMan5.0软件进行Meta分析。结果共纳入5个RCT共1277例患者。Meta分析结果显示:与2.5mg来曲唑相比,0.5mg来曲唑在治疗绝经后晚期乳腺癌的肿瘤应答率(OR=0.87,95%CI0.55～1.40,P=0.58)、临床获益率(OR=0.95,95%CI0.75～1.20,P=0.67)和主要不良反应发生率方面差异无统计学意义,而45个月病死率(OR=1.36,95%CI1.01～1.83,P=0.04)方面差异有统计学意义。5个RCT均未提供可进行两组生存质量比较的相关数据,但2个RCT认为不同剂量对生存质量影响无差异。结论现有证据表明0.5mg来曲唑不影响既往抗雌激素治疗失败的绝经后晚期乳腺癌患者的临床疗效,但对远期生存和生存质量的影响还不明确,有待进一步研究证实。

Objective To evaluate the efficacy and safety of oral letrozole administration with a dosage of 0.5mg versus 2.5mg daily in the treatment of terminal breast cancer in postmenopausal patients.Methods Clinical data of randomized controlled trials（RCTs） involving letrozole 0.5mg or 2.5mg in the treatment of terminal breast cancer in postmenopausal patients were retrieved from the database Cochrane library,PubMed,EMBASE,CBM,CNKI,VIP etc.In addition,references and review articles were also manually retrieved. The Cochrane handbook 5.0.0was used for methodological grade evaluation and Cochrane collaboration＇s RevMan 5.0software was used for Meta analysis.Results Five RCTs were included with a total of 1277patients.Meta-analysis showed no significant difference existed between 2.5mg and 0.5mg group in respect of overall tumor response rate（OR=0.87,95%CI：0.55-1.40,P=0.57）,clinical benefit rate（OR=0.95,95% CI：0.75-1.20,P=0.67）and the incidence of major adverse events,while significant difference was found between the two groups on overall survival（OR=1.36,95% CI：1.01-1.83,P=0.04）.Although it was found in 2RCTs that the quality of life was similar in the two groups,no sufficient evidence was found to assess the effect of letrozole on quality of life in postmenopausal patients with terminal breast cancer.Conclusion It is indicated by present study that 0.5mg letrozole is effective and welltolerated in the treatment of terminal breast cancer in postmenopausal women in whom antiestrogens treatment failed,but it remains uncertain as long-term survival and improvement in quality of life are concerned,and further study with large-scale RCTs is warranted.