# Case report: EGFR fusion mutation combined with EGFR amplification responds to EGFR-TKI therapy

## TL;DR

Two patients with rare EGFR mutations and amplification in lung cancer responded to EGFR-TKI therapy.

## Contribution

Reports two cases of EGFR fusion mutations with amplification responding to EGFR-TKI treatment in NSCLC.

## Key findings

- EGFR fusion mutations combined with amplification can respond to EGFR-TKI therapy.
- One patient with EGFR-MACF1 fusion and amplification showed antitumor response to EGFR-TKI.
- EGFR fusion mutations and amplification are rare in NSCLC but may benefit from EGFR-TKI treatment.

## Abstract

Given their good antitumor effects, epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are standard first-line therapy for EGFR-sensitive mutations, including exon 19 deletions and exon 21 L858R mutations. EGFR fusion mutations and EGFR amplification are very rare in non-small cell lung cancer (NSCLC). We describe 2 patients with NSCLC harboring EGFR fusion mutations (EGFR-MACF1 and EGFR-GNAT3) combined with EGFR amplification. Both patients received EGFR-TKI treatment, and 1 of them showed an antitumor response.