First-line single-agent cetuximab in elderly patients with metastatic colorectal cancer. A phase II clinical and molecular study of the Spanish group for digestive tumor therapy (TTD)

PurposeTo evaluate the efficacy and safety of first-line single-agent cetuximab in fit elderly patients with metastatic colorectal cancer, as well as potential molecular predictive factors for efficacy.Patients and methodsPatients aged 70 or older with metastatic CRC without criteria for frailty and no prior treatment for advanced disease were treated with single-agent cetuximab 400 mg/m2 followed by weekly 250 mg/m2 until disease progression or unacceptable toxicity.ResultsForty-one patients were included. Two patients achieved a complete response and 4 patients had a partial response for an overall response rate of 14.6%. Fifteen patients (36.6%) remained stable. Median time to progression was 2.9 months and median overall survival 11.1 months despite two-third of patients received chemotherapy at progression. Forty-five percent of EGFR gene copy number positive patients by FISH were progression-free at 12 weeks, in contrast with 12% of FISH negative patients (p = 0.04). Grade 3 skin toxicity was reported in 5 patients (12.2%). Hypersensitivity infusion reactions were not reported and there were no toxic deaths.ConclusionCetuximab is a safe monoclonal antibody with moderate activity in first-line metastatic colorectal cancer, but the present study does not support the use of cetuximab as single-agent in first-line fit elderly patients with metastatic CRC.