Page 24 - Head and neck surgery

Cells of the undifferentiated, nonkeratinizing type is sensitive to radiotherapy. In addition,

unilateral or bilateral lymph node metastasis is common on presentation. As a result, external

beam radiotherapy, covering the nasopharynx, bilateral parapharyngeal space and the neck, is the

treatment of choice for all stages of NPC on first presentation.

• Through the use of ionizing radiation, tumour control
is achieved by the formation of secondary electrons
causing double-strand DNA breaks in nuclei leading

to cell death.

• Duplicating chromosomes are more vulnerable to
radiation, leading to a preferential destruction of
tumour cells over normal tissues.

• Eradicates tumour cells while minimizing damage to

surrounding normal tissues