PIK3CA对埃克替尼治疗EGFR基因突变的非小细胞肺癌病人的疗效预测

目的探讨PIK3CA对埃克替尼治疗EGFR基因突变的非小细胞癌（NSCLC）病人疗效预测价值。方法首先应用ARMS法对确诊肺腺癌标本给予EGFR基因突变检测。对于EGFR检测阳性肺腺癌标本应用免疫组化蛋白定性法进行PIK3CA表达状态分析。对EGFR检测阳性者给予埃克替尼治疗，观察PIK3CA高表达组与低表达组埃克替尼治疗后的无进展生存期（PFS）。结果在62例EGFR突变的肺癌病人中，48.38%同时存在PIK3CA高表达。在PIK3CA表达阳性病人应用埃克替尼后中位疾病PFS 10.5个月（95% CI:5.6~15.4）；PIK3CA表达阴性的病人应用埃克替尼后中位疾病PFS 17.0个月（95% CI:10.1~23.8）。PIK3CA低表达病人用埃克替尼治疗的应答率、中位PFS、EGFR-TKIs耐药率均有较高的趋势（χ2=7.16，P < 0.05）。结论在EGFR突变的接受埃克替尼治疗的NSCLC病人，检测PIK3CA表达状态有助于鉴别出EGFR-TKIs治疗有效较低的病人，提前进行干预，从而延长病人中位PFS。

Predicting the efficacy of taking icotinib in the non-small cell lung cancer patients with EGFR gene mutation by PIK3CA

ObjectiveTo investigate the usage of PIK3CA in predicting the efficacy of taking icotinib in the non-small cell lung cancer (NSCLC) patients with EGFR gene mutation.MethodsFirst, the ARMS method was used to detect the mutation of EGFR gene in the specimens of lung adenocarcinoma.Then, for EGFR-positive lung adenocarcinoma specimens, immunohistochemistry was used to analyze the expression status of PIK3CA.After that, icotinib was given to EGFR-positive patients, and progression-free survival (PFS) was observed for patients with high-expression PIK3CA and low-expression PIK3CA.ResultsAmong 62 lung cancer patients with EGFR mutation, 48.38% had high expression of PIK3CA.After applying icotinib in PIK3CA-positive patients, the median disease progression-free survival period reached 10.5 months(95% CI:5.6-15.4), and the median disease progression-free survival period for PIK3CA-negative patients taking icotinib was 17.0 months (95% CI:10.1-23.8).The response rate, median PFS, and EGFR-TKIs resistance rates of patients with low expression of PIK3CA increased significantly after taking icotinib, and the differences were significant(χ2=7.16, P < 0.05).ConclusionsFor the NSCLC patients who have received EGFR-TKIs treatment, the detection of the expression status of PIK3CA can help to identify the patients with low efficacy, so early intervention can be adopted to extend the PFS.