1. Base of the tongue (posterior third of the tongue), vallecula, and anterior surface of the epiglottis
2. Posterior wall of the oropharynx
3. Soft palate and uvula
4. Tonsils and faucial pillars.

Early tumours T1 T2 N0 are treated by external beam irradiation including the adjacent lymph node bearing areas bilaterally. Localized accessible tumours of the lateral base of tongue may be suitable for a radioactive implant boost.

Advanced tumours T3 T4 N0 N1 N2 N3 should be considered for a twice daily radiotherapy schedule or concurrent chemotherapy with radiotherapy if the patient is fit.

Surgical resection with appropriate reconstruction followed by postoperative irradiation may be indicated for advanced disease. Resection of an extensive base of tongue carcinoma may require a total glossectomy and a total laryngectomy to prevent tracheal aspiration. Radiotherapy alone is used if the patient is in poor condition.

Radiotherapy is the treatment of choice for most cancers. Some localized superficial lesions of the soft palate and uvula may be suitable for a gold seed or iridium implant, or local excision. The remainder and those with lymph node metastases are treated by external beam irradiation.

Early tumours are treated by external beam irradiation. Well lateralized lesions are usually treated with a unilateral technique to spare the contralateral salivary glands. Larger tumours may be suitable for a twice daily radiation schedule or radiation with concurrent chemotherapy.

More advanced tumours should be considered for combined treatment with surgery and radiotherapy. If the patient is not fit for surgery or is unresectable but still suitable for radical treatment, accelerated radiotherapy with concomitant boost or concurrent chemotherapy with radiotherapy can be employed. Radiotherapy alone is used if the patient is in poor condition.