Systematic Review and Meta-Analysis of Resection Sequence in Synchronous Colorectal Liver Metastasis: Primary vs. Liver First.

BACKGROUND

This present systematic review and meta-analysis aims to compare overall survival (OS), disease-free survival (DFS), morbidity and mortality outcomes in patients undergoing colorectal first (CRf) versus liver first (Lf) resections with synchronous colorectal liver metastases.

METHODOLOGY: A literature search was performed in PubMed, Cochrane Central trials register, and Google Scholar databases. This was conducted in line with current PRISMA guidelines. 95% confidence intervals were calculated for the primary endpoints and odds ratios for secondary endpoints. The Cochrane Q test and the measurement of inconsistency test were used to assess the degree of heterogeneity among the included studies.

RESULTS

Fifteen studies were included with a total of 8611 patients from 2010 to 2025. A statistically significant survival benefit was seen in the overall 1-year survival of the CRf group compared to the Lf group, with no significant difference in 3- and 5-year follow-up. In addition, a statistically significant benefit in 1-, 3-, and 5- year DFS rates was seen in the CRf group when compared to the Lf group. No significant difference was seen in major morbidity and 90-day mortality, and failure to proceed to the second resection stage.

CONCLUSION

DFS was significantly increased in the CRf group compared to the Lf group, with no difference in secondary outcomes. One-year OS was also found to be higher in the CRf group; however, this finding likely reflects the heterogeneity of the included studies and perioperative course after hepatic resections. To our knowledge, this is the first meta-analysis to demonstrate such a significant difference of one strategy over the other. However, caution should be used in the interpretation of these results due to the lack of available randomized control trials.