Concurrent chemoradiotherapy for unresectable head and neck cancers

Abstract

The survival rates of unresectable patients of head and neck squamous cell cancer treated by surgery or radiotherapy used to be poor, but since concurrent chemoradiotherapy (CRT) has become a standard treatment for unresectable cancer, the survival rates of unresectable cancers have significantly improved compared to radiotherapy alone. CRT of accelerated/hyperfractionated radiotherapy has also significantly improved the survival rates of unresectable cancer compared to radiotherapy alone, but the survival rates for unresectable cancers treated by CRT of accelerated/hyperfractionated radiotherapy are equal to those of CRT of standard fractionated radiotherapy. The incidence of severe late adverse events such as dysphagia and mandible bone necrosis, which might reduce a patient's QOL, is not different between CRT and radiotherapy alone. Neoadjuvant chemotherapy of cisplatin/5FU plus docetaxel (TPF) combined with CRT or CRT with cetuximab is expected to improve the survival rates of unresectable cancers. However, these therapies can not be provided as standard treatment until their usefulness has been proved by randomized control studies to show that these therapies improve survival rates compared to the conventional CRT regimen. The survival rates of unresectable oropharyngeal cancers treated with CRT are significantly better than those of laryngeal and hypopharyngeal cancers. The survival rate of patients who are human papilloma virus (HPV) positive in oropharyngeal cancer is significantly better than those who are HPV negative. In future, we should stratify the oropharyngeal cancers into HPV status for clearly evaluating the efficacy of the new CRT strategy.