Based on preclinical data, showing that EGFR expression inhibits OPG expression and increases RANKL expression (5, 6), we hypothesized that the earlier observed increased EGFR gene expression in EGFR+ NSCLC (8, 9) may lead to an altered shift of RANKL expression or RANKL: OPG ratio and thereby promote bone metastases in EGFR+ NSCLC. Here, EGFR is linked to non-small cell lung carcinoma.