Pulmonary Metastasectomy in Colorectal Cancer: A Population-Based Retrospective Cohort Study Using the Korean National Health Insurance Database

PURPOSE: The study aimed to investigate the current status and prognostic factors for overall survival in patients who had undergone pulmonary metastasectomy for colorectal cancer. MATERIALS AND METHODS: The data of 2,573 patients who had undergone pulmonary metastasectomy after surgery for colorectal cancer between January 2009 and December 2014 were extracted from the Korean National Health Insurance Service claims database. Patient-, colorectal cancer–, pulmonary metastasis–, and hospital-related factors were analyzed using the Kaplan-Meier method, log-rank test, and Cox proportional hazards analysis to identify prognostic factors for overall survival after pulmonary metastasectomy. RESULTS: The mean age of the patients was 60.9±10.5 years; 66.2% and 79.1% of the participants were male and had distally located colorectal cancer, respectively. Wedge resection (71.7%) was the most frequent extent of pulmonary resection; 21.8% of the patients underwent repeated pulmonary metastasectomies; 73% of pulmonary metastasectomy cases were performed in tertiary hospitals; 53.9% of patients were treated in Seoul area; 82% of patients received chemotherapy in conjunction with pulmonary metastasectomy. The median survival duration was 51.8 months. The 3- and 5-year overall survival rates were 67.7% and 39.4%, respectively. In multivariate analysis, female sex, distally located colorectal cancer, pulmonary metastasectomy-only treatment, and high hospital volume (> 10 pulmonary metastasectomy cases/yr) were positive prognostic factors for survival. CONCLUSION: Pulmonary metastasectomy seemed to provide long-term survival of patients with colorectal cancer. The female sex, presence of distally located colorectal cancer, and performance of pulmonary metastasectomy in high-volume centers were positive prognostic factors for survival.