Adjuvant therapy with cetuximab for locally advanced squamous cell carcinoma of the oropharynx: results from a randomized, phase II prospective trial

Abstract

Background: Cetuximab combined with radiotherapy (RT) is a treatment option for head and neck cancer. The objectives of this randomized, phase II trial were to evaluate the efficacy and safety of cetuximab maintenance therapy following definitive RT with concomitant cetuximab in patients with oropharyngeal cancer.

Patients and methods: Ninety-one patients with stage III-IV M0 oropharyngeal tumors were randomly assigned to the treatment with accelerated concomitant boost RT (69.9 Gy) + cetuximab or the same treatment with the addition of 12 consecutive weeks of cetuximab maintenance therapy. The primary end point was locoregional control (LRC) at 1 year.

Results: LRC at 1 year was superior among patients in the experimental arm, treated with cetuximab maintenance (59% versus 47%). However, LRC was similar between both arms after 2 years of follow-up, as a result of increased locoregional recurrences after the first year in the maintenance group. Patients treated with adjuvant cetuximab do recover very soon from toxic effect after combined treatment.

Conclusions: Twelve weeks of cetuximab maintenance therapy after concomitant cetuximab + RT in locally advanced oropharyngeal carcinoma is feasible and improves clinical outcomes measured at 1 year. This improvement is not maintained after the second year suggesting that epidermal growth factor receptor blockade is not sufficient to completely eliminate the minimal residual disease.