Surgical Resection of a Single Colorectal Lung Metastasis is Associated With Best Survival

INTRODUCTION: The management of solitary colorectal cancer metastases to the lungs after resection of the primary colon cancer is controversial. Surgical resection of a metastatic tumor in the lungs may be associated with improved survival.

METHODS: A retrospective analysis was performed using the National Cancer Database for patients diagnosed with colon cancer (2010-2020). Patients with solitary colon cancer metastasis to the lungs after resection of the primary site were included in the study. We performed Kaplan-Meier survival analysis among the different treatment modalities. We also performed a multivariable Cox regression analysis to determine the factors associated with all-cause mortality.

RESULTS: A total of 2976 patients met the inclusion and exclusion criteria and presented with solitary colorectal cancer metastasizing to the lungs after resection of the primary tumor. Among them, 305 patients (10%) underwent surgical resection of the metastasis, 157 (5%) received radiation therapy, and 2514 (85%) received no local treatment to the metastasis (conservative therapy). Patients who underwent surgical resection had a significant survival advantage, with a 5-y survival rate of 42.7% compared to 29.7% for radiation therapy and 23.9% for conservative management (P < 0.001). On multivariate analysis, surgical resection was associated with improved survival (hazard ratio: 0.68; 95% confidence interval: 0.58, 0.80; P < 0.001).

CONCLUSIONS: Surgical resection of a single metastatic colon cancer in the lung after resection of the primary tumor is associated with improved survival. Patients with solitary colorectal lung metastases without any signs of tumors outside the chest should undergo appropriate cardiopulmonary testing and multidisciplinary evaluation for surgical resection.