Predicting Limited Survival After Resection of Synchronous Colorectal Liver Metastases: a Propensity Score Matched Comparison Between The Primary First And The Simultaneous Strategy.

BACKGROUND: The best surgical approach to treat synchronous colorectal liver metastases (CRLM) remains unclear. Here, we aimed to identify prognostic factors associated with limited survival comparing patients undergoing primary-first resection (PF) and simultaneous resection (SR) approaches. METHODS: We retrospectively reviewed clinical data of 217 patients who underwent resection for synchronous CRLMs between January 1, 2011, and December 31, 2021. There were 133 (61.2%) PF resection and 84 (38.8%) SRS. The two groups of patients were compared using propensity score matching (PSM) analysis and cox analysis was performed to identify prognostic factors for overall survival (OS). RESULTS: After PSM, two groups of 71 patients were compared. Patients undergoing SR had longer operative time (324 ± 104 min vs 250 ± 101 min; p < 0.0001), similar transfusion (33.3% vs 28.1%; p = 0.57), and similar complication rates (35.9% vs 27.2%; p = 0.34) than patients undergoing PF. The median overall survival and 5-year survival rates were comparable (p = 0.94) between patients undergoing PF (48.2 months and 44%) and patients undergoing SR (45.9 months and 30%). Multivariate Cox analysis identified pre-resection elevated CEA levels (HR: 2.38; 95% CI: 1.20-4.70; P = .01), left colonic tumors (HR: 0.34; 95% CI: 0.17-0.68; P = .002), and adjuvant treatment (HR: 0.43; 95% CI: 0.22-0.83; P = .01) as independent prognostic factors for OS. CONCLUSIONS: In the presence of synchronous CRLM, right colonic tumors, persistent high CEA levels before surgery, and the absence of adjuvant treatment identified patients characterized by a limited survival rate after resection. The approach used (PF vs SR) does not influence short and long-term outcomes.