Predictors of R0 resection and overall survival after oxaliplatin-based chemotherapy for synchronous potentially resectable colorectal liver-only metastases: a real-world retrospective study

For patients with synchronous potentially resectable colorectal liver-only metastases (CRLM-only), conversion chemotherapy followed by R0 liver resection offers a curative opportunity. However, real -world data on the efficacy of oxaliplatin-based regimens and the factors that determine successful conversion remain limited. To evaluate the conversion rate, survival outcomes, and independent predictors of R0 resection and overall survival (OS) in a real-world cohort of patients treated with oxaliplatin-based conversion chemotherapy. This single-center retrospective study included 158 consecutive patients with synchronous potentially resectable CRLM-only who received oxaliplatin-based conversion chemotherapy at the First Affiliated Hospital of Nanchang University between January 2013 and December 2023. The primary endpoint was the rate of R0 liver resection. Secondary endpoints were objective response rate (ORR), progression-free survival (PFS), and OS. Multivariate logistic regression was used to identify independent predictors of R0 resection, and multivariate Cox regression to identify independent prognostic factors for OS. Of the 158 patients, 61 (38.6%) achieved R0 resection. Objective response (OR = 28.4, P < 0.001) and fewer liver metastases ( ≥ 4 vs 1: OR = 0.05, P < 0.001) independently predicted successful conversion. Multivariate Cox analysis confirmed that treatment response (HR = 3.59, P < 0.001), maximal metastatic diameter (HR = 2.11, P < 0.001), R0 hepatectomy (HR = 3.54, P < 0.001), and targeted therapy (HR = 2.74, P < 0.001) were independent determinants of OS. R0 hepatectomy was an independent predictor of PFS. Although targeted therapy improved objective response, it did not independently increase the R0 resection rate. Response to oxaliplatin-based conversion chemotherapy and the number of liver metastases are the key drivers of R0 resection, while long-term survival is independently influenced by tumor response, metastatic burden, R0 resection, and targeted therapy. These findings support individualized treatment planning and underscore the need to integrate radiological response with anatomical feasibility; further refinement may come from incorporating molecular biomarkers.