Table 3.

Multivariate analysis of factors affecting acquired T790 M mutation by binary logic regression.

		All patients (n = 102)			Patients using TKI as the first line (n = 80)
		HR	95% CI	p-value	HR	95% CI	p-value
Age at diagnosis (year)		0.984	0.924–1.048	0.621	0.971	0.906–1.041	0.411
Gender (M/F)		0.794	0.168–3.758	0.771	0.507	0.069–3.722	0.504
Subtype of EGFR
	E19del	1.000			1.000
	L858 R or L861Q	0.450	0.087–2.315	0.339	0.313	0.061–2.449	0.313
Tumor size (cm)		1.256	0.817–1.929	0.299	1.328	0.776–2.274	0.301
Duration of TKI use (month)		1.147	1.006–1.308	0.040	1.175	0.994–1.389	0.059
De novo T790 M		3.565	0.656–19.381	0.141	6.351	0.721–55.965	0.096

Abbreviations: TKI, tyrosine kinase inhibitor.