Several patients displayed uncommon mutations or double mutations including T790M….In the subgroup with uncommon mutations (n = 25), median PFS, RR, and DCR for gefitinib versus erlotinib were 6.4 and 5.3 months (HR, 1.109; 95% CI, 0.464 to 2.653; P = .815), 25.0% and 42.9% (P = .419), and 66.7% and 71.4% (P = .829), respectively.

CONTRADICTING EVIDENCE: ...also suffered from lung adenocarcinoma in her right upper lobe and bone metastasis in her right scapula at her age of 37...She was treated with gefitinib, an epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) because of EGFR mutation (L747-S752 del)...Her bone metastasis became resistant after 1-year treatment...Bone metastasis had an additional EGFR mutation (T790M).

CONTRADICTING EVIDENCE:...Here, we present an in vivo imaging model for brain tumors using human cancer cell lines, including the EGFR-L858R/T790M-positive H1975 lung adenocarcinoma cells...KM12SM colorectal cancer cells containing the TPM3-NTRK1 gene fusion. Human lung adenocarcinoma H1975 cells, harboring an EGFR‐L858R‐sensitive mutation or an EGFR‐T790M‐resistant mutation, were resistant to the first‐generation EGFR‐TKI gefitinib, but were sensitive to the third‐generation EGFR‐TKI osimertinib.