Uncommon mutations in a cohort of Chinese NSCLC patients and outcomes of first-line EGFR-TKIs and platinum-based chemotherapy.

OBJECTIVE

Data on the clinical activity of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in patients with non-small-cell lung cancer (NSCLC) and uncommon mutations remain insufficient. This study aimed to investigate the effect of first-line EGFR-TKIs or platinum-based chemotherapy in NSCLC patients with uncommon mutations.

METHODS

We retrospectively enrolled 504 patients with -mutant NSCLC. The clinical characteristics and treatment outcomes were collected and compared between patients with common and uncommon -mutant NSCLC.

RESULTS

Seventy patients (13.9%) harboring uncommon mutations were included. Thirty of these patients received EGFR-TKIs and 40 received platinum-based chemotherapy as first-line therapy. The objective response rate (ORR) and median progression-free survival (mPFS) of patients treated with TKIs in the uncommon mutation group was significantly inferior to that in the common mutation group (ORR: 23.3% . 51.8%, P=0.003; mPFS: 7.1 . 10.9 months, P<0.001). In the uncommon group, mPFS was similar between first-line EGFR-TKIs treatment and platinum-based chemotherapy (7.1. 6.1 months, P=0.893). In patients with G719X or L861Q mutations, the mPFS was longer in the first-line EGFR-TKIs treatment group than in the chemotherapy group, but the difference was not statistically significant (G719X: 8.2 . 5.8 months, P=0.061; L861Q: 7.6 . 4.1 months, P=0.872). Multivariate analyses identified adenocarcinoma (P=0.003) as the independent predictive factor for PFS in patients with uncommon mutations who were treated with first-line EGFR-TKIs.

CONCLUSIONS

The current study demonstrated that the effect of first-line EGFR-TKIs was similar to that of platinum-based chemotherapy in patients with uncommon -mutant NSCLC. Adenocarcinoma was the independent predictive factor for PFS in uncommon -mutant NSCLC patients treated with first-line EGFR-TKIs.