Sequence For Surgical Resection of Primary Lung Tumor For Oligometastatic Non-Small Cell Lung Cancer.

Abstract Background Differing surgical series for the treatment of primary lung tumor with synchronous oligometastatic stage IV non-small cell lung cancer (NSCLC) have been published; however, outcomes remain ambiguous. Methods Patients with synchronous oligometastatic stage IV NSCLC treated from 2005 to 2017 were enrolled to identify the impact of treatment sequence (primary lung resection versus systemic treatment) on progression-free survival (PFS) and overall survival (OS). Results Fifty-one patients received tumor resection (84% adenocarcinoma, 55% non-smokers, and 65% driver gene mutation). Resection occurred before or after systemic treatment in 33 (64.7%) and 18 (35.3%) patients, respectively. Patients who received resection first were older (62.1 vs. 54 year) and at a less advanced intrathoracic stage (18% vs. 44%). No significant differences were noted regarding perioperative complication (30% vs. 28%), length of hospital stay (9.0 vs. 10.5 days), percentage of disease progression (91% vs. 94%), overall death (70% vs. 78%), median PFS (14.0 vs. 22.8 months) and OS (44.6 vs. 53.2 months). Patients with single-organ metastasis had significantly longer PFS and OS than those with oligometastases (17.5 vs. 12.8 months, p=0.040 and 55.6 vs. 39.8 months, p=0.035), respectively. Multivariable Cox analysis identified non-solitary metastasis as the only independent predictor of PFS (hazard ratio 2.27; 95% CI, 1.07-4.81, p=0.033). Conclusions Primary lung resection before or after induction systemic therapy may benefit patients with oligometastatic NSCLC. Future randomized clinical trials examining the effect of treatment sequence is recommended.