Erlotinib or Radiotherapy in the Treatment of Brain Metastasis from EGRF-Mutant NSCLC?

Mutations in the epidermal growth factor receptor (EGFR) are common in non-small cell lung cancer (NSCLC). Tyrosine kinase inhibitors (TKIs) are the mainstay of the treatment of patients with EGFR mutations. By inhibiting phosphorylation of intracellular domain of the EGFR, TKIs disrupt signal transduction in the ras/eaf/MAPK and PI3K/Akt pathways, which are known to play important roles in cell growth and proliferation, angiogenesis, tumor invasion, and metastasis. In nonselected patients with NSCLC, TKIs achieved a 10% response in the EGFR. Thus, patient populations who benefited from these agents were investigated, and high response rates and long survival times were achieved with both firstand secondline therapies in specific subgroups [1-3].