In the univariable analysis, prolonged PFS was significantly associated with an ECOG PS of ≤2 (p < 0.001), common EGFR mutations (p < 0.001), no brain metastasis (p = 0.001), no bone metastasis (p < 0.001), no liver metastasis (p < 0.001), and no pleural metastasis (p = 0.007) (Table 2). Here, EGFR is linked to bone metastasis.