Erlotinib usage after prior treatment with gefitinib in advanced non-small cell lung cancer: A clinical perspective and review of published literature

Table 5 Potential factors predicting response to erlotinib following prior gefitinib therapy

Previous response to gefitinib (most important)

Longer duration of response to prior gefitinib

Female gender

Adenocarcinoma histology

Non smokers

East Asian ethnicity

EGFR mutation positive status1

Good performance status

Chemotherapy cycles in between gefitinib and erlotinib

¹Indicates presence of sensitizing EGFR mutations (exon 19 deletion or exon 21 L858R mutation). EGFR: Epidermal growth factor receptor.