Prognostic Factors in EGFR Mutation-positive Patients With Bone Metastases from Lung Adenocarcinoma.

Background/Aim: This study analyzed prognostic factors in patients with lung adenocarcinoma and bone metastases who tested positive for epidermal growth factor receptor (EGFR) mutations. Patients and Methods: We retrospectively reviewed the records of 117 patients with lung adenocarcinoma and bone metastases who were followed up at a single institution for 0.2 months to 66 months. Of these 117 patients, 45 were EGFR mutation-positive and further analysis was performed for these patients. Median survival times and five-year survival rates were investigated according to performance status (PS), oligometastatic status, radiotherapy and EGFR-tyrosine kinase inhibitor (TKI) administration. Results: The five-year survival rate of EGFR mutation-positive patients was 9.2%, and median survival time was 22.7 months; their mean age was 69.5 years. Many EGFR mutation-positive patients had a PS of 2, and the median survival time showed significant differences according to PS (0/1/2 vs. 3/4) and oligometastatic status. Conclusion: Although there was no difference in the mean survival time between patients receiving or not receiving bone radiotherapy, the treatment effectively reduced pain and prevented paralysis. As a first-line treatment in EGFR mutation-positive patients, first- or second-generation TKIs followed by third-generation TKIs showed favorable outcomes.