Liver Resection in Synchronous Bilobar versus Unilobar Colorectal Liver Metastases: A Retrospective Analysis of Oncological Outcomes and Patient Survival

Introduction: Resection of colorectal liver metastasis has emerged as the standard treatment. Our study compares oncological outcomes of patients with resected synchronous bilobar versus unilobar colorectal liver metastasis. Methods: This retrospective study presents long-term follow-up data of 105 consecutive patients with primary colorectal cancer and synchronous liver metastasis. All patients underwent primary tumor and metastasis resections between 2007 and 2019. Results: Fifty-five patients with bilobar and 50 patients with unilobar colorectal liver metastases were included. No significant difference in overall, tumor-specific, or recurrence-free survival was observed between patients with bilobar and unilobar metastases. After case-control matching, the results were confirmed in patients with similar tumor burdens. In the multivariate analysis, chemotherapy following liver metastasis resection was a significant prognostic factor associated with improved overall survival (hazard ratio 0.518, 95% confidence interval: 0.302–0.888, p = 0.017). Conclusion: Overall survival, as well as tumor-specific and recurrence-free survival, did not differ between patients with unilobar and bilobar liver metastasis. These findings contribute to the understanding that primary tumor and metastasis resection in eligible patients improve long-term outcomes.