PMC9608750_01
Reverse transcription PCR of negative/positive controls (1, 3, 4) and biopsy specimen before osimertinib administration from the patient (2). (1) No template (negative control). (2) The biopsy specimen before osimertinib administration was negative for METex14del. (3) METex14del wild type sample (negative control). (4) METex14del positive sample (positive control). MET, mesenchymal-epithelial transition gene.
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f1
The re-biopsy specimen was positive for EGFR L858R and de novo T790M, although the biopsy specimen of the primary tumor before osimertinib administration was negative for METex14del using local reverse transcription PCR ( Figure 1 ).
(A) Baseline chest computed tomography (CT) before tepotinib administration showing the tumor in the right lower lobe. (B) Chest CT 2.0 months after tepotinib administration showing a partial response (tumor shrinkage rate: 34.5% in diameter).
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f2
We administered daily tepotinib (500 mg/day) to the patient as a further-line therapy, and achieved a partial response (tumor shrinkage rate: 34.5% in diameter) after 2.0 months ( Figures 2A, B ).