e20646 Background: Epidermal growth factor receptor (EGFR) mutation is a strong predictor of response to EGFR tyrosine kinase inhibitors (TKI). However, response duration is variable. The predictive value of EGFR mutation for response is superior to previously reported clinical predictors, namely female gender, Asian ethnicity, smoking status, and histology. It is unclear, however, whether any clinical characteristics have additive predictive value for duration of response to EGFR-TKI. Here, we attempted to identify clinical predictors
