Related Experiment Video
Updated: Jul 4, 2026
Ultra-Fast Amplicon-Based Next-Generation Sequencing in Non-Squamous Non-Small Cell Lung Cancer
Published on: September 8, 2023
Are there any ethnic differences in molecular predictors of erlotinib efficacy in advanced non-small cell lung
Myung-Ju Ahn1, Byeong-Bae Park, Jin Seok Ahn
1Division of Hematology-Oncology, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine.
Purpose:
This study investigated possible molecular predictors of outcome in Korean patients with advanced non-small cell lung cancer treated with erlotinib.
Experimental Design:
One hundred and twenty patients received erlotinib and were followed prospectively. Ninety-two tissue samples were analyzed for epidermal growth factor receptor (EGFR) gene mutations (exons 18, 19, and 21), 88 for EGFR gene amplification by real-time PCR, and 75 for EGFR protein expression by immunohistochemistry.
Results:
The overall tumor response rate was 24.2% (complete response, 4; partial response, 25) with 56.7% of disease control rate. With a median follow-up of 23.6 months, the median time to progression (TTP) was 2.7 months and the median overall survival was 12.9 months. EGFR gene mutations were found in 26.1% (24 of 92), EGFR gene amplification in 40.9% (36 of 88), and EGFR protein expression in 72% (54 of 75). There was a strong association between EGFR gene mutations and gene amplification (gamma = 0.241). Patients with EGFR gene mutations or gene amplification showed both better response rate (58.3% versus 16.2%, P < 0.001; 41.7% versus 17.3%, P = 0.012) and TTP (8.6 versus 2.5 months, P = 0.003; 5.8 versus 1.8 months, P < 0.001) and overall survival (not reached versus 10.8 months, P = 0.023; not reached versus 10.1 months, P = 0.033). By multivariate analysis, EGFR gene mutation was the only significant molecular predictor for TTP (hazard ratio, 0.47; 95% confidence interval, 0.25-0.89).
Conclusions:
Our findings indicate that EGFR gene mutation is a more predictive marker for improved TTP than EGFR gene amplification in erlotinib-treated Korean non-small cell lung cancer patients. Prospective studies from diverse ethnic backgrounds are required to determine the exact role of these molecular markers.
