Background: To evaluate the treatment response of EGFR tyrosine kinase inhibitor (EGFR-TKI) for persistent ground-glass nodule (GGN) in patients with stage IV non-small cell lung cancer (NSCLC).
Methods: This is a retrospective study from 2010 to 2015...
Background: To evaluate the treatment response of EGFR tyrosine kinase inhibitor (EGFR-TKI) for persistent ground-glass nodule (GGN) in patients with stage IV non-small cell lung cancer (NSCLC).
Methods: This is a retrospective study from 2010 to 2015. Patients who received EGFR-TKI for stage IV NSCLC and had concurrent GGN(s) that existed more than 3 months on chest CT scans were included in the study. For each nodule, chest CT images before and after treatment of EGFR-TKI were reviewed to evaluate objective response, which was defined as complete or partial response in size.
Results: A total of 83 persistent GGNs were identified in 64 patients. Forty-one (64%) were female and the median age was 58.3 (range, 45 - 82). EGFR mutation was identified at the primary tumor or metastatic lesion in 50 (78%) patients. The median duration of EGFR-TKI was 13.0 months. Objective response was observed in 44 (53%) GGNs. EGFR mutation of deletion in exon 19 [odds ratio (OR), 3.04; 95% confidence interval(CI), 1.18-7.88] and EGFR-TKI treatment for more than 1 year [OR, 2.7; 95% CI, 1.09-6.66] were significantly associated with objective response.
Conclusion: Half of the persistent GGNs showed objective response to EGFR-TKI treatment in patients with stage IV NSCLC. Objective response was more common in patients with EGFR exon 19 deletion or EGFR-TKI treatment of more than 1 year.