Prognostic value of surgical intervention in advanced lung adenocarcinoma: a population-based study

Background: Surgical intervention is generally not considered as a treatment option in patients with advanced non-small cell lung cancer (NSCLC). Accumulating data suggest that surgery may have beneficial effects for these advanced patients. However, no evidence supports the significance of primary tumor resection (PTR) and metastatic tumor resection (MTR) in patients with stage IV lung adenocarcinoma (LUAD). Methods: A total of 32,497 patients diagnosed with primary stage IV LUAD were selected through the Surveillance, Epidemiology, and End Results (SEER) database. Possible confounders were eliminated by propensity score matching (PSM). The overall survival (OS) and lung cancer-specific survival (LCSS) were estimated as the primary endpoints. Furthermore, the independent prognostic factors of patients with the surgical intervention were retrospectively analyzed. Results: Patients underwent surgical intervention had better OS and LCSS than those who did not (P=0.001 for OS; P<0.001 for LCSS). Meanwhile, patients who underwent surgery combined with lymph node dissection had better survival outcomes (P<0.001 for OS and LCSS) in the K-M analysis. For different metastatic sites, PTR was beneficial to the survival of patients with isolated lung metastases (LUM) and multiple organ metastases (MOM) (LUM: P=0.041; MOM: P=0.003). As for metastatic surgery, no patients were found to benefit from resection of metastatic tumor [bone metastasis (BOM): P=0.696; brain metastasis (BRM): P=0.951; LUM: P=0.402; MOM: P=0.365]. Conclusions: Surgical intervention strategies can prolong survival to some extent, depending on different sites of metastasis and highly selected patients.