Radiation therapy uses special equipment to deliver high doses of radiation (beam of x-rays) to cancerous tumours, to kill or damage them so they cannot grow or spread. Normal cells may be affected by radiation, but most appear to recover fully from the effects of the treatment. Radiation therapy affects only the tumour and the surrounding area. Some cancers are very sensitive to radiation but not all. Radiotherapy is usually given in small doses over a period of time; this is known as a course. Each small dose of radiotherapy (often called a 'fraction') takes a few minutes to deliver and one fraction of radiotherapy is delivered per day, Monday to Friday. Radiotherapy is not usually delivered on weekends. A course of radiotherapy can be between 1 to 35 fractions, dependent on the aim of the treatment, the type of cancer and the site that is being treated. Prior to starting radiotherapy a planning appointment is organised when a scan of the treatment area is performed and permanent tiny skin tattoos are often placed which are used as reference marks for each fraction of radiotherapy. A doctor who manages your radiotherapy is called a radiation oncologist. Some common side effects of radiation treatment include: Fatigue or tiredness During the first 2 weeks of treatment, a faint and short lasting redness may occur on your skin. Dryness and peeling of the skin may occur in 3 to 4 weeks. The skin over the treatment area may become darker. Mucositis (inflammation of the lining of the mouth) is a temporary side effect that may happen when radiation is given to the head and neck area. Radiation to the head and neck area can increase your chances of getting cavities. Before starting radiation therapy, notify your dentist and plan for a complete check-up. Radiation to hair bearing areas may cause temporary and sometimes permanent hair loss. When radiation treatments include the chest area and upper abdomen, the lungs can be affected and you may experience shortness of breath or cough. The oesophagus (tube from throat to stomach) may develop swelling and inflammation causing nausea, vomiting and discomfort when swallowing. Radiation to the abdomen and pelvis may result in inflammation to intestines, again causing nausea, vomiting, or diarrhoea. Radiation to the pelvis may also cause inflammation of the bladder causing urinary frequency, urgency and stinging. The long term effects of radiotherapy are very site specific and, along with the treatment side effects, will be discussed in detail during your clinic appointment and prior to signing a consent form for the radiation treatment.