Primary tumor consolidative therapy improves the outcomes of patients with advanced EGFR-mutant lung adenocarcinoma treated with first-line osimertinib
Journal
Therapeutic advances in medical oncology
Journal Volume
16
Date Issued
2024
Author(s)
Wu, Jia-Jun
Tseng, Jeng-Sen
Zheng, Zhe-Rong
Chu, Cheng-Hsiang
Chen, Kun-Chieh
Huang, Yen-Hsiang
Hsu, Kuo-Hsuan
Yang, Tsung-Ying
Chang, Gee-Chen
Abstract
Background: Patients with advanced epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma (LAD) inevitably experience drug resistance following treatment with EGFR-tyrosine kinase inhibitors (TKIs).
Objectives: We aimed to analyze the effect of primary tumor consolidative therapy (PTCT) on patients treated with first-line osimertinib.
Design and methods: This retrospective cohort study was conducted in patients with advanced stage III or stage IV LAD with EGFR-sensitizing mutations (exon 19 deletion or L858R mutation) with disease control after first-line osimertinib. A curative dose of primary tumor radiotherapy or primary tumor resection was classified as PTCT. We compared the progression-free survival (PFS) and overall survival (OS) of patients with and without PTCT.
Results: This study included 106 patients with a median age of 61.0 years, and of those, 42% were male and 73.6% were never-smokers. Exon 19 deletion was observed in 67.9%, 30.2% had a programmed cell death ligand 1 (PD-L1) tumor proportion score <1%, 33.0% had brain metastasis, and 40.6% had oligometastasis. In all, 53 (50%) patients underwent PTCT. Patients who underwent PTCT demonstrated significantly better PFS [30.3 (95% confidence interval (CI), 24.1-36.4) versus 18.2 (95% CI, 16.1-20.2) months; p = 0.005] and OS [not reached versus 36.7 (95% CI, 32.5-40.9) months; p = 0.005] than patients who did not. A multivariate analysis showed that PTCT was an independent factor associated with better PFS [hazard ratio (HR), 0.22; 95% CI, 0.10-0.49; p < 0.001] and OS [HR, 0.10; 95% CI, 0.01-0.82; p = 0.032]. The PFS benefits of PTCT were consistent across subgroups, and the HR tended to be lower in patients aged <65 years, males, smokers, stage IVB disease, L858R, PD-L1 expression ⩾1%, non-oligometastasis, and brain metastasis.
Conclusion: Of the patients with advanced EGFR-mutant LAD, those who underwent PTCT had a significantly better survival outcome than those who did not. The survival benefits were consistent across different subgroups.
Subjects
EGFR mutation
PD-L1
lung adenocarcinoma
osimertinib
primary tumor radiotherapy
primary tumor resection
SDGs
Type
journal article