the Food and Drug Administration approved osimertinib (Tagrisso, AstraZeneca Pharmaceuticals) for adult patients with locally advanced, unresectable (stage III) non-small cell lung cancer (NSCLC) whose disease has not progressed during or following concurrent or sequential platinum-based chemoradiation therapy and whose tumors have EGFR exon 19 deletions or exon 21 L858R mutations, as detected by an FDA-approved test.

...EGFR mutation status was confirmed by ARMS fluorescence PCR, including 4 cases of 19del mutant, 4 cases of 21L858R mutant, and 2 cases of wild type; 3. ...

...- The tumor harbors an Ex19del or Ex21-L858R substitution (based on tumor tissue or plasma [ctDNA] assessment)....

...• The tumour harbours one of the 2 common EGFR mutations known to be associated with EGFR-TKI sensitivity (Ex19 deletions, L858R), either alone or in combination with other EGFR mutations. ...

...Tested and confirmed to be EGFR mutation-positive (including exon 19 deletion and exon 21 L858R); 6. ...

...The tumour harbours one of the 2 common EGFR mutations known to be associated with EGFR-TKI sensitivity (Ex19del, L858R)....

...The resected lung adenocarcinoma should have actionable EGFR mutation, which is limited to L858R or exon 19 deletion....

...The tumour harbours one of the 2 common EGFR mutations known to be associated with EGFR-TKI sensitivity (Ex19 deletions, L858R), either alone or in combination with other EGFR mutations....

...Patients with EGFR sensitizing mutations (Ex19del or L858R)....

...The resected lung adenocarcinoma should have actionable EGFR mutation, which is limited to L858R or exon 19 deletion....

Half (9/18) of the patients had EGFR exon 21 L858R mutations and the other half (9/18) had EGFR exon 19del mutations. Amongst all 15 patients who completed efficacy assessment after neoadjuvant osimertinib, the response rate (RR) was 73.3% (11/15) and the disease control rate (DCR) was 100% (15/15)....Interim analysis from this study indicated neoadjuvant osimertinib as an effective and feasible treatment in patients with resectable stage II-IIIB EGFRm NSCLC.

Biopsy of a liver lesion demonstrated adenocarcinoma positive for TTF-1 and Napsin-A by immunohistochemistry. An EGFRL858R mutation was detected in the tumor with targeted NGS using the Illumina MiSeqDx platform...she was started on 80 mg osimertinib QD. She had an excellent response, with shrinkage of all sites of disease and resolution of brain metastases.Imaging performed every ~2 months showed a continued response, until 8.5 months after initiation of osimertinib when the patient was found to have growth of a liver lesion.

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.