Effect of Maintenance Anti-EGFR Therapy on Survival in RAS Wild-Type Metastatic Colorectal Cancer: Real-World Data

Objective: This study aimed to evaluate the impact of anti-epidermal growth factor receptor (anti-EGFR)–based maintenance therapy administered after first-line chemotherapy combined with anti-EGFR treatment on progression-free survival (PFS) and overall survival (OS) in patients with RAS wild-type metastatic colorectal cancer (mCRC), using real-world data.

Methods: Patients followed at a single center between 2015 and 2025 were retrospectively analyzed. A total of 37 RAS wild-type patients who achieved disease control after first-line chemotherapy combined with anti-EGFR therapy were included. Patients were divided into a maintenance therapy group (n = 19) and an active surveillance group (n = 18). Survival analyses were performed using the Kaplan–Meier method, groups were compared using the log-rank test, and a landmark approach was applied to minimize immortal time bias.

Results: At a median follow-up of 27.4 months, median PFS was 11.4 months in the maintenance group and 5.4 months in the surveillance group, without reaching statistical significance (P = .133). In contrast, median OS was significantly longer in the maintenance group (56.9 months vs. 9.6 months; P = .041). Additionally, higher rates of transition to subsequent lines of therapy were observed in patients receiving maintenance therapy.

Conclusion: Anti-EGFR–based maintenance therapy was associated with numerically prolonged PFS and improved treatment continuity in patients with RAS wild-type mCRC. Although a significant difference in OS was observed, this finding should be interpreted cautiously given the limited sample size, retrospective design, and potential influence of selection bias and subsequent therapies. Larger prospective studies are warranted to better define the role of anti-EGFR maintenance therapy in clinical practice.

Cite this article as: Çokgezer S, Artan S, Topuz S, et al. Effect of maintenance anti-EGFR therapy on survival in RAS wild-type metastatic colorectal cancer: real-world data. Cerrahpaşa Med J 2026, 50, 0069, doi: 10.5152/cjm.2026.26069.