Palliative surgery is effective in patients with EGFR-mutant lung adenocarcinoma with pleural metastasis

Pleural metastasis is a common metastatic pattern in patients with epidermal growth factor receptor-mutant lung adenocarcinoma (EGFR-LUADm); however, the value of palliative surgery for these patients remains controversial. The purpose of the present study aims to investigate whether palliative surgery benefits in stage IVA LUADm patients with pleural metastasis, who achieved complete remission of pleural lesions following targeted therapy. From November 2014 to November 2023, patients with stage IVA EGFR-LUADm with pleural metastasis at Shanghai Pulmonary Hospital were retrospectively included in this study. All the patients received EGFR-tyrosine kinase inhibitor (TKI) monotherapy. The patients were divided into surgical- and non-surgical treatment subgroups. To reduce any selection bias, a 1:2 propensity score matching (PSM) was performed before comparing oncological outcomes between the two groups. The Kaplan-Meier method and log-rank test were used to identify the prognostic factors of these patients. A total of 134 patients who met the inclusion and exclusion criteria were enrolled in this study. Of the 134 patients, 13 received EGFR-TKI monotherapy followed by palliative surgical treatment (the surgical group), and 121 received EGFR-TKI monotherapy alone (the non-surgical group). No significant differences in the baseline characteristics were observed between the subgroups. After PSM, the surgical and non-surgical groups comprised 13 and 26 patients, respectively. The survival analysis showed that the patients in the surgical group had significantly better progression-free survival (PFS) than those in the non-surgical group {surgical vs. non-surgical: median PFS: 43 [95% confidence interval (CI): 30-not available] vs. 11 (95% CI: 10-26, P<0.001)}. Compared with EGFR-TKI monotherapy, palliative surgery combined with EGFR-TKI treatment prolonged the PFS of pleural metastatic EGFR-LUADm patients. A subset of EGFR-LUADm patients with pleural metastasis might be suitable for palliative surgery.