Treatment outcomes of maintenance therapy with cetuximab in metastatic colon cancer in a real-world setting: A single center retrospective analysis

Abstract Purpose Fluoropyrimidine (FP) and oxaliplatin-based chemotherapy is the standard first-line treatment for metastatic colorectal cancer (mCRC); however, oxaliplatin-induced neuropathy critically affects the quality of life of patients. Maintenance strategies with FP plus bevacizumab have been well established; nonetheless, the real-world outcomes of maintenance therapy with FP and cetuximab are unclear. We investigated the clinical outcomes of patients who underwent maintenance therapy with cetuximab. Methods We retrospectively identified and analyzed patients with mCRC who were treated between 2012 and 2021 with first-line oxaliplatin-based induction chemotherapy (IC) and patients treated with maintenance therapy after IC. Results A total of 112 patients were treated with IC. Among them, 48 patients underwent maintenance therapy (same IC regimen without oxaliplatin). The most common reason for the discontinuation of IC was peripheral neuropathy (n = 40, 83%). For the IC of the maintenance group, 3, 26, and 19 patients were treated with CAPOX (capecitabine/oxaliplatin), mFOLFOX6 (FP/leucovorin/oxaliplatin) plus bevacizumab, and mFOLFOX6 plus cetuximab. The best overall response of maintenance therapy was a partial response in 7 patients and stable disease in 30 patients The median progression-free survival (PFS) of maintenance therapy and overall survival (OS) was 4.83 months and 25.6 months in the bevacizumab group, and 5.98 months and 32.4 months in the cetuximab group, respectively. Conclusions Maintenance therapy with FP and cetuximab is a feasible strategy for appropriate mCRC patients. Further large-scale randomized studies are needed to validate the efficacy of anti-epidermal growth factor receptor-based maintenance therapy.