Advancement in the Management of Synchronous Colorectal Liver Metastasis: A Comprehensive Review of Surgical, Systemic, and Local Treatment Modalities.

Synchronous colorectal liver metastases (sCRLMs) present a complex therapeutic challenge requiring multimodal management strategies due to their complex tumor biology, variable disease progression, and the need to balance oncologic control with liver function preservation. This systematic review evaluates recent advancements in surgical approaches, systemic therapies, and local treatment modalities. A comprehensive literature search was conducted across major databases (PubMed, EMBASE, and Cochrane) for studies published between 2013 and 2024. Studies evaluating surgical techniques, perioperative outcomes, systemic therapy integration, and local treatments for sCRLM were included. Quality assessment was performed using the Newcastle-Ottawa Scale for observational studies and the Cochrane risk-of-bias tool for randomized controlled trials (RCTs). Analysis of nine primary studies encompassing 3,856 patients revealed evolving treatment paradigms. This review includes English-language studies (2013-2024) on adult patients (≥18 years) with sCRLM, covering RCTs, cohort, and case-control studies reporting survival, perioperative outcomes, or quality of life (≥12 months follow-up). Exclusions include case reports (<10 patients), metachronous metastases, conference abstracts, reviews without data, unclear methodology, duplicates, and animal/in-vitro studies. Staged resection demonstrated superiority over the simultaneous approach in recent analyses (win ratio 1.59, 95%CI 1.47-1.71). This indicates that patients undergoing staged resection had a 59% higher likelihood of achieving better outcomes (such as survival or fewer complications) compared to those undergoing simultaneous resection. The narrow confidence interval suggests strong statistical reliability of this finding. Minimally invasive techniques showed comparable outcomes to open surgery, with acceptable morbidity rates (21.7%) even in simultaneous resections. Neoadjuvant chemotherapy with targeted agents achieved high resectability rates (97%) and significant response rates (66%). The presence of liver metastases negatively impacted immunotherapy efficacy, suggesting the need for tailored approaches. Management of sCRLM has evolved toward a more personalized approach incorporating advanced surgical techniques, targeted therapies, and novel treatment sequencing. While staged resection may offer advantages in selected cases, treatment decisions should be individualized based on patient and disease characteristics. Future research should focus on optimizing patient selection and treatment sequencing through prospective trials.