CONCLUSION: Definitive chemoradiotherapy administered for unresectable stage IVB head and neck cancer has the potential of achieving long-term disease-free survival in up to two-thirds of the patients with a low risk of complications. [PubMed-indexed for MEDLINE].he disease-free survival rate at five years was 68%. Local, regional, and distant failure rates were 21%,14%, and 7% respectively. Most of the patients (79%) experienced transient mucositis during treatment.