[Molecular targeted therapy and tailor-made therapy for lung cancer]

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• Somatic mutations in the epidermal growth factor receptor (EGFR) gene are linked to gefitinib response in lung cancer.
• Previous studies indicated EGFR mutations are more common in specific demographics and tumor types.

Purpose of the Study:

• To investigate the efficacy of gefitinib in non-small cell lung cancer (NSCLC) patients with EGFR mutations.
• To identify molecular mechanisms of resistance to gefitinib.

Main Methods:

• Retrospective analysis of EGFR gene mutations in tumors from 37 NSCLC patients treated with gefitinib.
• Assessment of gefitinib efficacy (CR/PR) and patient survival based on EGFR mutation status.
• Screening for K-ras mutations and acquired T790M mutations in resistant tumors.

Main Results:

• EGFR mutations were identified in 22 out of 37 patients.
• Gefitinib was effective in 68.2% of patients with EGFR mutations versus none without.
• Patients with EGFR mutations had significantly longer survival (p = 0.0005).
• Gefitinib was ineffective in patients with K-ras mutations.
• Three of four tumors from patients with acquired resistance harbored a secondary T790M mutation.

Conclusions:

• Molecular targeted therapy with tyrosine kinase inhibitors (TKIs) like gefitinib is effective in lung cancer patients with EGFR mutations.
• Analysis of resistance mechanisms, such as the T790M mutation, is crucial for developing personalized therapies.