Liver-first approach to stage IV colon cancer with synchronous isolated liver metastases

Background: The only possibility for cure in patients with colon adenocarcinoma (CAC) with isolated liver metastases (ILM) is resection of both primary and metastatic tumors. Little is known about the implication of the sequence in which a colectomy and hepatectomy are performed on outcomes. This study analyzes whether resection sequence impacts clinical outcomes. Methods: The National Cancer Database was queried for CAC cases with hepatic metastases from 2010-2015 with exclusion of extrahepatic metastases. We compared patients treated with a liver-first approach (LFA) to those treated with a colectomy-first or simultaneous approach using Kaplan Meier and multivariable Cox proportional hazards analysis. Results: In 21,788 CAC patients identified, the LFA was uncommon (2%), but was associated with higher rates of completion resection of remaining tumor (41% vs. 22%, P<0.001). Patients selected for LFA were younger, less comorbid, and more commonly received upfront chemotherapy (P<0.05). The LFA was associated with increased median survival [34 months, 95% CI (30.5-39.6 months) vs. 24 months, 95% CI (23.7-24.6 months), logrank P<0.001] and decreased risk of death [HR 0.783; 95% CI (0.67-0.89), P=0.001]. Conclusions: The LFA to CAC with synchronous ILM is uncommon but is associated with greater likelihood of receiving chemotherapy prior to surgery and increased survival in selected candidates.