The prognosis after contraindicated surgery of NSCLC patients with malignant pleural effusion (M1a) may be better than expected

// Yijiu Ren 1, * , Chenyang Dai 1, * , Jianfei Shen 2, * , Yang Liu 2 , Dong Xie 1 , Hui Zheng 1 , Jiaxi He 2 , Wenhua Liang 2 , Gening Jiang 1 , Ke Fei 1 , Ping Yang 3 , Jianxing He 2 , Chang Chen 1 1 Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, People’s Republic of China 2 Department of Thoracic Surgery, First Affiliated Hospital of Guangzhou Medical University & Guangzhou Research Institute of Respiratory Disease, Guangzhou, People’s Republic of China 3 Division of Epidemiology, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA * These authors have contributed equally to this work Correspondence to: Chang Chen, e-mail: changchenc@hotmail.com Jianxing He, e-mail: drjianxing.he@gmail.com Keywords: lung cancer, surgery, malignant pleural effusion, prognosis, surveillance epidemiology and end-results database Received: November 03, 2015 Accepted: March 11, 2016 Published: April 4, 2016 ABSTRACT Although non-small cell lung cancer (NSCLC) with malignant pleural effusion (M1a) is generally contraindicated for surgery, several reports have demonstrated favorable prognosis. This study aimed to describe the results of surgical intervention in this disease. In this retrospective study, we evaluated NSCLC patients with ipsilateral malignant pleural effusion selected from Surveillance Epidemiology and End-Results database (SEER). Primary tumor resection was compared to no tumor resection in the overall survival (OS) and lung cancer-specific survival (LCSS). Multivariate analyses and propensity score matching were applied to compare the two groups. The study included 2,217 eligible patients. Primary tumor resection group was significantly associated with better OS and LCSS compared to no tumor resection group (the median survival time (MST), 20 vs 7 months; OS, p <0.001; LCSS, p <0.001). Multivariable analyses indicated that no primary tumor resection was associated with decreased OS (Hazard Ratio (HR), 2.136; p<0.001) and LCSS (HR, 2.053; p<0.001). In propensity score-matched pairs, better OS and LCSS were further validated in patients with ipsilateral malignant pleural effusion who underwent primary tumor resection compared to no tumor resection (MST, 20 vs 6 months; OS, p <0.001; LCSS, p <0.001). Similarly, multivariable analyses also indicated that no primary tumor resection was associated with decreased OS (HR, 2.309; p <0.001) and LCSS (HR, 2.301; p <0.001) for patients with ipsilateral malignant pleural effusion. In conclusion, the prognosis after contraindicated surgery of NSCLC patients with malignant pleural effusion (M1a) may be better than expected. Thus, subsequent studies should aim to identify patients who could benefit from surgery.