Data from Phase II Study of Cetuximab in Combination with Cisplatin and Radiation in Unresectable, Locally Advanced Head and Neck Squamous Cell Carcinoma: Eastern Cooperative Oncology Group Trial E3303

Purpose: Treatment with cisplatin or cetuximab combined with radiotherapy each yield superior survival in locally advanced squamous cell head and neck cancer (LA-SCCHN) compared with radiotherapy alone. Eastern Cooperative Oncology Group Trial E3303 evaluated the triple combination.Experimental Design: Patients with stage IV unresectable LA-SCCHN received a loading dose of cetuximab (400 mg/m2) followed by 250 mg/m2/week and cisplatin 75 mg/m2 q 3 weeks ×3 cycles concurrent with standard fractionated radiotherapy. In the absence of disease progression or unacceptable toxicity, patients continued maintenance cetuximab for 6 to 12 months. Primary endpoint was 2-year progression-free survival (PFS). Patient tumor and blood correlates, including tumor human papillomavirus (HPV) status, were evaluated for association with survival.Results: A total of 69 patients were enrolled; 60 proved eligible and received protocol treatment. Oropharyngeal primaries constituted the majority (66.7%), stage T4 48.3% and N2-3 91.7%. Median radiotherapy dose delivered was 70 Gy, 71.6% received all three cycles of cisplatin, and 74.6% received maintenance cetuximab. Median PFS was 19.4 months, 2-year PFS 47% [95% confidence interval (CI), 33%–61%]. Two-year overall survival (OS) was 66% (95% CI, 53%–77%); median OS was not reached. Response rate was 66.7%. Most common grade ≥3 toxicities included mucositis (55%), dysphagia (46%), and neutropenia (26%); one attributable grade 5 toxicity occurred. Only tumor HPV status was significantly associated with survival. HPV was evaluable in 29 tumors; 10 (all oropharyngeal) were HPV positive. HPV+ patients had significantly longer OS and PFS (P = 0.004 and P = 0.036, respectively).Conclusions: Concurrent cetuximab, cisplatin, and radiotherapy were well tolerated and yielded promising 2-year PFS and OS in LA-SCCHN with improved survival for patients with HPV+ tumors. Clin Cancer Res; 20(19); 5041–51. ©2014 AACR.