Efficacy of chemotherapy in epidermal growth factor receptor (EGFR) mutated metastatic pulmonary adenocarcinoma patients who had acquired resistance to first-line EGFR tyrosine kinase inhibitor (TKI)

Salvage chemotherapy is frequently used when tumour epidermal growth factor receptor (EGFR) mutated patients experience disease progression with first-line EGFR-tyrosine kinase inhibitor (TKI) treatment. However, the efficacy of salvage chemotherapy is still unknown.We retrospectively reviewed the chart records of our pulmonary adenocarcinoma patients between 2010 and 2013.Five hundred and six of the 1240 stage IV adenocarcinoma patients had an EGFR mutation and 338 received first-line EGFR-TKI treatment. In all, 169 patients in this group received salvage chemotherapy after failure of EGFR-TKI, and 102 patients were eligible for this study. The chemotherapy response rate of these 102 patients was 24.5%, with a median progression-free survival (PFS) of 4.5?months, and median survival time was 14.6?months. Patients who received pemetrexed-based chemotherapy had longer PFS and overall survival (OS), although the extent was statistically insignificant. Progression-free survival and OS were longer for patients who received combination chemotherapy than single-agent chemotherapy.Pemetrexed-based combination chemotherapy is preferred before a more efficient treatment strategy is found.