Microwave ablation as local consolidative therapy for patients with extracranial oligometastatic EGFR-mutant non-small cell lung cancer without progression after first-line EGFR-TKIs treatment.

OBJECTIVES

Evidence from multiple clinical trials showed that local consolidative therapy (LCT) improved survival in oligometastatic non-small cell lung cancer (NSCLC) patients. In the present study, we aim to explore the potential role of microwave ablation (MWA) as LCT for epidermal growth factor receptor (EGFR)-mutant advanced NSCLC patients with extracranial oligometastasis.

MATERIALS AND METHODS

From January 2015 to December 2018, a total of 86 EGFR-mutant stage IIIB or IV NSCLC patients with extracranial oligometastasis were enrolled for retrospective analysis. MWA was used as LCT for all oligometastatic lesions and/or primary tumors in 34 patients without progression after first-line EGFR-TKIs therapy (consolidation group), while the other 52 patients received only TKIs until disease progression (monotherapy group). We calculated and compared the progression-free survival (PFS) and overall survival (OS) of the two groups.

RESULTS AND CONCLUSION

Patients with MWA consolidation therapy had significantly improved PFS (median 16.7 vs. 12.9 months, HR 0.44, 95% CI 0.22-0.88, P = 0.02) and OS (median: 34.8 vs. 22.7 months, HR 0.45, 95% CI 0.24-0.88, P = 0.04) than monotherapy group. MWA for LCT was identified as the independent predictive factor for better PFS (HR 0.46, 95% CI 0.37-0.82, P < 0.01) and OS (HR 0.57, 95% CI 0.33-0.91, P = 0.02). Most toxicities were mild and well tolerated. No patient had to discontinue EGFR-TKIs because of MWA complications. These findings suggest that MWA as local consolidative therapy after first-line EGFR-TKIs treatment leads to better disease control and survival than TKIs monotherapy in EGFR-mutant advanced NSCLC patients with extracranial oligometastasis. MWA as a novel option of LCT might be considered for clinical management of these patients.