Multivariate analysis revealed that the longer duration of initial EGFR TKI use (OR 1.792, with ≥8months compared to <8months, p=0.004), better EGFR TKI responses (OR 1.611, with CR or PR compared to SD, p=0.006), presence of bone metastasis (OR 2.286, p<0.001) were correlates with a higher rate of T790M positivity (Figure 2). Here, EGFR is linked to bone metastasis.