Abstract:
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.