e15627 Background: Treatment options for refractory metastatic colorectal cancer (mCRC) remain limited. Regorafenib is commonly used in the late-line setting; however, outcomes vary substantially among patients in real-world practice. Rather than focusing on the causal efficacy of regorafenib, understanding the clinical contexts in which regorafenib-based strategies are associated with more favorable outcomes may provide practical guidance for patient selection and treatment planning. Methods: This retrospective observational study included patients with refractory mCRC treated with regorafenib at a single tertiary center between November 2015 and October 2024. All patients had received standard prior therapies, including fluoropyrimidines, oxaliplatin, irinotecan, anti-VEGF agents, and anti-EGFR agents when indicated. Progression-free survival (PFS) and overall survival (OS) were analyzed according to clinical and treatment-related factors, including prior treatment duration, metastatic pattern, feasibility of local treatment, and treatment strategies administered during regorafenib therapy. Results: A total of 123 patients were analyzed. The median OS was 8.4 months (IQR: 4.1–14.6), and the median PFS was 2.6 months (IQR: 1.7–5.8). Considerable heterogeneity in outcomes was observed. Patients with a prior stage IV treatment duration exceeding 18 months demonstrated significantly longer PFS and OS compared with those with shorter treatment histories. Similarly, patients who underwent local treatment, such as metastasectomy, radiotherapy, or ablation, during the course of regorafenib therapy exhibited more favorable survival outcomes. The presence of lung metastasis was also associated with prolonged PFS and OS compared with other metastatic patterns. These factors were consistently associated with improved outcomes within the regorafenib-treated cohort, whereas molecular characteristics such as KRAS status showed no clear association with survival. Conclusions: In this real-world cohort of refractory mCRC patients treated with regorafenib, survival outcomes varied widely and were strongly associated with clinical characteristics reflecting disease biology and treatment feasibility. Prolonged prior treatment duration, the presence of lung metastasis, and the ability to integrate local treatment were associated with more favorable PFS and OS. These findings suggest that regorafenib-based strategies are most commonly associated with better outcomes in patients with indolent disease phenotypes and preserved opportunities for multidisciplinary management, rather than indicating a uniform treatment effect across all patients.
Lin et al. (Thu,) studied this question.