Outcomes of First-Line Microwave Ablation of Treatment-Naive Epidermal Growth Factor Receptor-Mutated Advanced Lung Adenocarcinoma Treated with Tyrosine Kinase Inhibitors.

Purpose: To investigate the outcomes of first-line image-guided microwave ablation (MWA) plus tyrosine kinase inhibitors (TKIs) in untreated epidermal growth factor receptor (EGFR)-mutant advanced lung adenocarcinoma (LUAD) and to compare with TKIs alone.

Materials and methods: This retrospective cohort study included patients between December 2015 and December 2021 and was divided into 2 groups (Group A: first-line MWA+TKIs; Group B: TKIs alone). Progression-free survival (PFS) was the primary end point, whereas overall survival (OS) was the secondary end point and were compared via the Kaplan-Meier methods. Univariate and multivariate analyses were used to investigate the predictors of PFS and OS. Propensity score matching (1:1 ratio) was applied between Group B and the subgroup of complete ablation in Group A.

Results: A total of 117 patients were included (Group A: n = 43; Group B: n = 74). In a mean follow-up of 47.0 months (SD ± 19.4), Group A had significantly longer median PFS (19.0 vs 10.0 months; P < .001) and OS (41.0 vs 25.0 months; P = .044) than Group B. Predictors of PFS included first-line MWA (P < .001) and tumor stage (P = .020), while that of OS included first-line MWA (P = 0.039), tumor stage (P = 0.014), and usage of third-generation TKIs (P = 0.001). There were 23 pairs of patients obtained after propensity score matching (Group A1: complete ablation+TKIs; Group B1: TKIs alone). Group A1 had significantly longer median PFS (24.0 vs 10.0 months; P < .001) and OS (48.0 vs 24.0 months; P = .012) than Group B1.

Conclusions: First-line MWA significantly improved the outcomes of patients with untreated EGFR-mutant advanced LUAD treated with TKIs. Complete ablation predicts a better prognosis.