Primary tumour resection in non-small-cell lung cancer patients with ipsilateral pleural dissemination (M1a): a population-based study.

Abstract

Non-small-cell lung cancer (NSCLC) patients with ipsilateral pleural dissemination (M1a) are generally contraindicated for surgery. However, several small-sample studies have demonstrated that they might benefit from surgery. We investigated the effects of primary tumour resection on survival in these patients. Stage IV NSCLC patients with ipsilateral pleural dissemination were identified from the US National Cancer Institute Surveillance, Epidemiology and End Results database entries from 2010 to 2015. Survival analysis was performed before and after matching. Multivariable regression models were built to identify prognostic factors. Of the 5513 patients with ipsilateral pleural dissemination, 309 underwent primary tumour resection. In the entire cohort, surgery was associated with improved overall survival (OS) in both the unmatched and matched cohorts (both log rank, P < 0.001). In the surgery-recommended cohort, patients treated with surgery also had significantly longer OS before and after matching. Multivariable regression models showed that surgery was an independent favourable prognostic factor for OS [hazard ratio (HR) 0.56, 95% confidence interval (CI) 0.48-0.65; P < 0.001] and lung cancer-specific mortality (subhazard ratio 0.60, 95% CI 0.51-0.70; P < 0.001). Surgery was independently associated with improved survival in all subgroups except for those with pericardial effusion (P = 0.065) or N3 disease (P = 0.17). In the surgical cohort, patients who underwent lobe/bilobectomy had significantly better OS than those who underwent sublobar resection (log rank, P < 0.001). Inclusion of primary tumour resection in multimodal therapy of NSCLC was associated with improved survival in selected patients with ipsilateral pleural dissemination, except for those with pericardial effusion or N3 disease.