CSF1R and lung cancer: The association between high expression levels of CSF1R and lung cancer-specific mortality was stronger in never-smoking patients (log-rank p = 0.0027; HR = 2.90, 95% CI = 1.41−6.11, p = 0.0041) than in ever-smoking patients (log-rank p = 0.73; HR = 1.11, 95% CI = 0.59−2.00, p = 0.73).