Background:

Among patients with advanced lung cancer, 30-40% have bone metastases (BoM) at first diagnosis. However, the clinical characteristics and prognostic factors of BoM in patients with NSCLC harboring EGFR mutations are rarely reported. The aim of this study was not only to identify the clinical feature of NSCLC patients harboring EGFR mutations.

Methods:

This study enrolled patients with stage IV EGFR-mutant NSCLC treated with first-line EGFR-TKIs between January 2014 and December 2020. We divided patients into two groups: patients who had or not had BoM at initial diagnosis.

Results:

A total of 247 patients were enrolled in the final analysis. Progression-free survival (PFS) (12.6 vs 10.5 months, p = 0.002) and overall survival (OS) (49.7 vs 30.9 months, p = 0.002) in patients with initial BoM were shorter than those without BoM at initial diagnosis. The location of metastatic sites exhibited difference between these two groups and the number of extra thoracic metastasis was higher in BoM group. (p < 0.001). However, the incidence of T790M was higher in patients with BoM than those without BoM. (47.4% VS 33.9%, p = 0.042) Multivariate Cox regression analysis revealed sequential osimertinib treatment and the addition of anti-angiogenesis and denosumab therapy to patients with BoM improved OS.

Conclusion:

BoM was identified as an inferior prognostic factor for NSCLC patients with EGFR mutation, which may be due to extra thoracic metastasis. However, adding an anti-angiogenesis drug and denosumab to patients with BoM and sequential osimertinib treatment can provide survival benefits.