Abstract
Background: The oncologic benefit of liver resection for colorectal liver metastases (CRLM) in the setting of concurrent extrahepatic disease (EHD) is controversial. We performed a population-based, cross-sectional study to determine the practice patterns and overall survival (OS) of patients with CRLM + EHD who underwent liver resection. Methods: Patients with CRLM + EHD were identified using the California Cancer Registry from 2000 to 2019. Records were linked to the Office of Statewide Health Planning Inpatient Database. Patient demographics, clinical characteristics, and survival were compared between CRLM + EHD patients with and without liver resection. Results: Of 170 978 patients with CRLM, 62 003 (36%) had concurrent EHD (CRLM + EHD). In all, 3736 (6%) of CRLM + EHD underwent liver resection compared to 22% of patients with liver limited CRLM. Compared to CRLM + EHD without liver resection, CRLM + EHD with resection were younger, had fewer comorbidities, received higher frequencies of perioperative chemotherapy, and were more likely to have only a single site of EHD rather than multiple sites. Median OS was significantly higher for CRLM + EHD with resection compared to without (52 vs. 27 months, HR 0.46 [95% CI 0.44–0.47], p < 0.001). Regarding the location of EHD, this survival benefit was observed with liver resection for lung, peritoneal, intraabdominal lymph nodes, ovarian, and bone metastases. Conclusions: In a large population-based setting, subsets of CRLM + EHD patients that undergo liver resection are associated with prolonged survival. These results support surgery with thoughtful patient selection to optimize survival outcomes in this population. © 2024 The Author(s). Journal of Surgical Oncology published by Wiley Periodicals LLC.