Radiation Damage to the Face & Its Treatment

Introduction
Radiotherapy has been used for the treatment of cancer in people and animals for more than 100 years now. Similar to surgery, it is used for the local control of tumours and can either be used on its own or in conjunction with surgery. When radiotherapy is combined with surgery, it is most often used after the operation, once the wound has healed. This is called adjuvant radiotherapy. Radiotherapy given before surgery is called neoadjuvant radiation.

Indications for surgery and radiotherapy to the head include many types of oral tumours and tumours of the skin and subcutis that happen to be located on the head. Nasal tumours are usually treated with radiotherapy alone, but in some cases surgery is used after radiation to remove remaining neoplastic tissue. An extensive list of tumours of the head treated with radiotherapy alone or with a combination of surgery and radiotherapy can be found elsewhere.

Radiation penetrating tissue physically interacts with electrons, either ejecting them from the atom (ionisation) or exciting them to higher energy levels (excitation). The most important effect of ionisation and excitation is damage to the DNA by breaking strands or causing cross-linking. DNA damage can either lead to cell death, or it can be repaired by enzymes, resulting in the recovery of the cell, cell dysfunction or carcinogenesis. Besides this direct effect of radiation on cell DNA, radiation also generates free radicals and cytotoxic peroxides in the tissue, which in turn damage cell DNA. These effects of radiation naturally affect all cells within the area treated, whether neoplastic, or not, and major developments in radiotherapy since the discovery of X-rays have ensured that the effect of radiation to cancer cells is maximised while side effects are minimised. Fractionation of the dose given allows healthy tissue to recover between doses of radiation thus reducing side effects. More recently advances in tumour imaging and computer technology for the planning and delivery of radiotherapy have further allowed optimal delivery of radiation to cancer tissues while keeping damage to healthy tissues to a minimum. Such modalities include Stereotactic Radiation Therapy (SRT), Image-guided radiation therapy (IGRT), Intensity- Modulated Radiation Therapy (IMRT).  [...]