Locally advanced head and neck cancer treated with accelerated radiotherapy, the hypoxic modifier nimorazole and weekly cisplatin: Results from the DAHANCA 18 phase II study

PURPOSE/OBJECTIVE: A phase II clinical trial evaluating the feasibility and outcome of treating locally advanced head and neck squamous cell carcinoma (HNSCC) with accelerated radiotherapy, the hypoxic modifier nimorazole and weekly cisplatin.

MATERIAL AND METHODS: A total of 227 patients with stage III or IV HNSCC of the larynx, oropharynx, hypopharynx, or oral cavity where included between January 2007 and December 2010. The prescribed radiotherapy (RT) dose was 66-68 Gy in 2 Gy fractions, 6 F/W. The hypoxic radiosensitiser nimorazole was given orally at a dose of 1200 mg/m(2) before each fraction. Concomitant cisplatin (40 mg/m(2)) i.v. was given once a week for a maximum of six cycles. Outcome data were evaluated in terms of loco-regional tumour control (LRC), event-free survival (EFS) and overall survival (OS). Morbidity data were evaluated based on the DAHANCA routine registration. Human papillomavirus (HPV)-status was estimated by immunohistochemical staining of p16.

RESULTS: Included were 178 (78%) men and 49 (22%) women with a median age of 57 years. All except five patients received RT as prescribed. At least five series of cisplatin was given to 164 (72%) of the patients, and 149 patients (66%) received the full dose of nimorazole. The five-year actuarial LRC, EFS and OS rates were 80%, 67% and 72%, respectively. The LRC rates according to site were: oropharynx: 88%, larynx: 77%, hypopharynx 72% and oral cavity 49%, respectively. HPV/p16 staining was obtained in 141 of the 150 oropharyngeal cancers. Of these, 112 (79%) were p16 pos and 29 (21%) were p16 neg. LRC for the p16 neg oropharyngeal cancers was poorer than for the p16 pos (74% vs. 91%; p = 0.02). Tube feeding during treatment was necessary for 146 (64%) patients. At 12 months this number was reduced to 6%.

CONCLUSION: The treatment was tolerable in this cohort of locally advanced HNSCC patients. Acute and late toxicity was comparable to similar studies of chemoradiotherapy, and the outcome superior to the data reported in the literature. This strongly indicates that RT of advanced head and neck cancer must include as well hypoxic modification, accelerated fractionation as chemoradiotherapy to yield optimal outcome.