The optimal treatment of HNCUP remains controversial and lacks evidence from prospective randomized trials. The management of these patients relies primarily on surgery and radiotherapy. The role of radiotherapy in sterilizing putative mucosal sites remains controversial. The main debate concerns the extent of the radiation field. Although pan-mucosal irradiation from the nasopharynx to the hypopharynx and bilateral neck nodes reduces the risk of emergence of a mucosal primary or a nodal relapse, it has been associated with significant toxicity and long-term morbidity (mostly xerostomia and dysphagia). Most single institution retrospective studies have not shown any advantage for more extensive irradiation.Therefore, elective mucosal irradiation may might be appropriate only for these patients.

Inclusion Criteria:

1. Carcinomas metastatic to cervical lymph node with unknown primary
2. Squamous cell carcinoma, poorly differentiated carcinoma, or undifferentiated carcinoma
3. All patients must be suitable to attend regular follow-up and undergo toxicity assessment.
4. Stage T0, N1-3, M0 disease
5. Karnofsky score over 60
6. No significant cardiac, chest, gastrointestinal or renal morbidities

Exclusion Criteria:

1. Previous radiotherapy to the head and neck region
2. Previous malignancy except non-melanoma skin cancer
3. Previous or concurrent illness which in the investigators opinion would interfere with either completion of therapy or follow-up