Initial experience of radiotherapy plus cetuximab for Japanese head and neck cancer patients

Abstract

In Japan, cetuximab with concurrent bioradiotherapy (BRT) for squamous cell carcinoma of head and neck (SCCHN) was approved in December 2012. We herein report our initial experience of BRT, with special emphasis on acute toxicities of this combination therapy. Thirty-one non-metastatic SCCHN patients who underwent BRT using cetuximab between July 2013 and June 2014 were retrospectively evaluated. All patients received cetuximab with a loading dose of 400 mg/m(2) one week before the start of radiotherapy, followed by 250 mg/m(2) per week during radiotherapy. The median cycle of cetuximab was seven cycles and the median dose of radiotherapy was 70 Gy. Twenty-five patients (80.6%) accomplished planned radiotherapy and six cycles or more cetuximab administration. Six patients (19.4%) discontinued cetuximab. Grade 3 dermatitis, mucositis and infusion reaction occurred in 19.4%, 48.3% and 3.2%, respectively. One patient experienced Grade 3 gastrointestinal bleeding caused by diverticular hemorrhage during BRT. Grade 3 drug-induced pneumonitis occurred in two patients. The response rate was 74%, including 55% with a complete response. BRT using cetuximab for Japanese patients with SCCHN was feasible as an alternative for cisplatin-based concurrent chemoradiation, although longer follow-up is necessary to evaluate late toxicities.

Keywords: acute toxicity; cetuximab; head and neck cancer; initial experience; radiotherapy.

Fig. 1.

(A) Hypopharyngeal tumor with pool of saliva and normal mucosa before the start of bioradiotherapy. (B) Decrease in the tumor bulk and development of Grade 3 mucositis during bioradiotherapy. (C) Confluent mucositis one month after the end of bioradiotherapy.

Fig. 2.

(A) Grade 3 dermatitis with contact bleeding occurred at one week after bioradiotherapy. (B) Resolution of dermatitis at 4 weeks after bioradiotherapy.

Fig. 3.

Drug-induced lung injury (DLI) developed at 2 weeks after the end of bioradiotherapy in patient with oropharynx cancer. He also had diverticular hemorrhage at the second week of bioradiotherapy. (A) Bilateral interstitial infiltration and consolidation can be seen on chest X-ray image. (B) Chest computed tomography scan shows widespread ground-glass opacity with peribroncho-vascular thickness that was predominant bilaterally in upper lung.