EGFR and non-small cell lung carcinoma: Small studies and case reports suggest limited activity of the third-generation anti-EGFR TKI, osimertinib on NSCLC with EGFR exon 20 insertions (9, 10), with lower response rates and shorter progression-free survivals compared to NSCLC with EGFR exon 19 or exon 21 mutations.