Second-line treatment of advanced NSCLC: Comparison of efficacy of erlotinib and chemotherapy

Molecular targeted therapy based on tyrosine kinase inhibitors, directed at the epidermal growth factor receptor (EGFR) is one of novel options for management of NSCLC. Erlotinib is EGFR tyrosine kinase inhibitor used for treatment of the advanced NSCLC. This presented study is focused on comparison of erlotinib and chemotherapy efficacy in the second line treatment of the advanced NSCLC. DCR and PFS became the primary endpoints. Total number of patients was 290. A group treated with chemotherapy in the second line consisted of 150 patients and a group treated with erlotinib in the second line consisted of 140 patients. Comparison of DCR was performed using Fisher's exact test, visualization of PFS was performed using Kaplan-Meier survival curves and differences were tested using the log-rank test. Genetic testing was performed using PCR direct sequencing. In the group treated with chemotherapy 2 CR, 23 PR and 51 SD were achieved vs. 5 CR, 10 PR and 55 SD in the group treated with erlotinib in the second line. DCR in patients treated with chemotherapy was 54.0% vs. 51.3% in patients without EGFR mutation treated with erlotinib (p=0.707); in patients harboring EGFR mutation, treated with erlotinib (n=9) outstanding results were achieved: 4 CR, 2 PR and 3 SD (not tested). Median of PFS in patients treated with chemotherapy was 2.1 months vs. 1.9 months in patients without EGFR mutation (p=0.879) vs. 8.4 months in patients harboring EGFR mutation treated with erlotinib (p=0.017). Results of analysis show that even patients without EGFR mutation are able to benefit from erlotinib treatment in the second line. The efficacy (DCR, PFS) of erlotinib in patients without EGFR mutation was comparable with chemotherapy. The treatment efficacy in a subgroup of patients harbouring EGFR mutation treated with erlotinib was significantly better than in patients without EGFR mutation.