Decision-Making for Ablation of Colorectal Liver Oligometastases Patients: A 10-Year Retrospective Study of Survival Outcomes Based on Right-Versus Left-Sided Primary Tumor Location

ObjectiveTo develop a prognostic model for optimizing management of colorectal liver oligometastases (CLOM) patients with different primary tumor locations who underwent thermal ablation (TA).Materials and MethodsThe reporting of this retrospective study conforms to STROBE guidelines. A total of 525 CLOM patients who underwent TA from 3 hospitals between 2011 and 2021 were enrolled. Firstly, intra and extrahepatic disease-free survival (DFS) and overall survival (OS) for CLOM patients with different primary tumor locations were analyzed. Then, cox regression models were used to identify independent factors predicting OS. Finally, a prognostic score was developed to identify CLOM patients benefiting from TA. All patient details were de-identified.ResultsA total of 423 eligible patients were identified, with 762 CLOM (121 male, median age 59 years) and a median follow-up of 45.8 (IQR, 7.3-114.8) months. Independent predictors of OS were identified, including multiple liver metastases (<i>P</i> = .0085), right-sided colon cancer (<i>P</i> = .0210), tumor size ≥2 cm (<i>P</i> = .0273), and lymph node metastasis of primary colorectal cancer (<i>P</i> = .0302), termed as the "MRSL" score. On the basis of the best separation of MRSL score, patients were divided into high-risk (cutoff value ≥8) and low-risk groups (cutoff value <8). Further stratified analysis indicated that right-sided CLOM patients had shorter OS than left-sided patients in the high-risk group (54.9 vs 92.5 months, <i>P</i> = .0156). However, no significant difference in OS was observed between right-sided and left-sided CLOM patients in the low-risk group (97.7 vs 102.2 months, <i>P</i> = .28).ConclusionThe MRSL score-based model helps in selecting potential right-sided CLOM patients who benefit from TA.