Des Guetz Gaëtan, Uzzan Bernard, Nicolas Patrick, Schischmanoff Olivier, Perret Gerard-Yves, Morere Jean-François
Department of Oncology, APHP, Hôpital Avicenne, 125 route de Stalingrad, 93009 Bobigny, France.
Anticancer Res. 2009 May;29(5):1615-20.
Microsatellite Instability (MSI) status is a good prognostic factor for colorectal cancer (CRC) but its predictive value for chemosensitivity remains controversial. A previous meta-analysis (MA) in the adjuvant setting showed that MSI-high (H) status did not predict the efficacy of chemotherapy. The predictive value of MSI status on the effect of metastatic chemotherapy was investigated by MA.
Studies were identified by electronic search through PubMed, Embase and ASCO proceedings online databases, using several key words (colorectal cancer, chemotherapy, microsatellite instability). For each study, the ratio of response rate (RR), complete (CR) and partial response (PR) divided by stable disease and progression was calculated. From 190 articles and 100 abstracts, only eight independent studies were selected. The data were analysed with a random-effect model (due to heterogeneity between studies) using EasyMA software. Statistical calculations were performed on six studies representing 964 patients (mean age 63 years; 91 MSI-H; 873 microsatellite stable (MSS) tumours). A total of 287 patients received 5-fluorouracil (5FU)-based chemotherapy, whereas 678 patients received combinations of 5FU or capecitabine with oxaliplatin and/or irinotecan.
No benefit of metastatic chemotherapy in terms of RR for MSI-H patients compared with MSS patients was found. The global hazard ratio (HR) for RR was 0.82 (95% confidence interval, CI: 0.95; 0.65-1.03; p=0.09).
MSI status does not predict the effect of chemotherapy which is similar in MSI-H and MSS metastatic CRC tumours.
微卫星不稳定性（MSI）状态是结直肠癌（CRC）的一个良好预后因素，但其对化疗敏感性的预测价值仍存在争议。先前在辅助治疗背景下的一项荟萃分析（MA）表明，微卫星高度不稳定（MSI-H）状态不能预测化疗疗效。本荟萃分析研究了MSI状态对转移性化疗效果的预测价值。
通过电子检索PubMed、Embase和美国临床肿瘤学会（ASCO）会议论文在线数据库，使用多个关键词（结直肠癌、化疗、微卫星不稳定性）来识别研究。对于每项研究，计算缓解率（RR）、完全缓解（CR）和部分缓解（PR）与疾病稳定和进展的比例。从190篇文章和100篇摘要中，仅选择了8项独立研究。使用EasyMA软件，采用随机效应模型（由于研究之间存在异质性）对数据进行分析。对代表964例患者（平均年龄63岁；91例MSI-H；873例微卫星稳定（MSS）肿瘤）的6项研究进行了统计计算。共有287例患者接受了基于5-氟尿嘧啶（5FU）的化疗，而678例患者接受了5FU或卡培他滨与奥沙利铂和/或伊立替康的联合化疗。
与MSS患者相比，未发现MSI-H患者在RR方面从转移性化疗中获益。RR的总体风险比（HR）为0.82（95%置信区间，CI：0.95；0.65 - 1.03；p = 0.09）。
MSI状态不能预测化疗效果，MSI-H和MSS转移性CRC肿瘤的化疗效果相似。
