This retrospective study investigated the potential use of portal-phase ring enhancement on contrast-enhanced CT as a prognostic imaging biomarker in patients with colorectal liver metastases treated with bevacizumab-based chemotherapy, and explored its association with radiomic features. The baseline and 3-month CT scans of 80 patients with histologically confirmed colorectal liver metastases treated with bevacizumab were retrospectively analyzed. Portal-phase ring enhancement was observed in 32.5% of patients at baseline and was found to be significantly associated with worse overall survival, as also confirmed at follow-up evaluation. Radiomic analysis identified tumor sphericity as the feature most strongly correlated with ring enhancement, enabling the development of a modestly predictive model. Overall, portal-phase ring enhancement emerged as a reproducible marker associated with poor prognosis. Integration of this conventional imaging feature with shape-based radiomic metrics may improve early risk stratification and support more personalized therapeutic decision-making.