On the other hand, EGFR TKI (gefitinib or erlotinib) both produced somewhat similar higher response rate (around 25%) in general Taiwan adenocarcinoma NSCLC patients, while the median overall survival time didn't longer than chemotherapy treated patients. A recent prospective study of gefitinib in chemonaive adenocarcinoma NSCLC patients showed that the objective response rate was lower to be only 1.1% among EGFR mutation negative patients.