What is Radiation Therapy?

Radiation therapy uses high doses of radiation (a stream of high-energy particles or waves, such as X-rays, gamma rays, or electrons) to kill cancer cells by preventing them from reproducing.

Other names for radiation therapy include radiotherapy or X-ray therapy. The radiation is delivered in a way that enables tumour – lethal radiation doses to reach the tumour while avoiding surrounding healthy tissue, which limits unnecessary damage. Several different angles of approach and techniques are used to deliver each treatment. This will vary depending on the type, size and location of the targeted tumour.

Radiation therapy may be used alone or in combination with other treatments (such as chemotherapy or surgery), and can be delivered before, during or after these. The radiation therapy team chooses which technique or combination of techniques to use and when they will be delivered in order to give the most effective treatment for each individual patient. Most radiation therapy treatments are given in small doses every day over several weeks, in order to maximise tumour cell kill and minimize side effects.

How does it Work?

Normal tissue in the body is comprised of cells that grow and divide. This process is controlled by DNA strands within each cell, which contain the 'code' or instructions that determine that cell's activity. Cancer cells grow and divide more rapidly than normal cells, as a result of changes in their DNA. Radiation breaks the DNA strands in cells, which prevents them from growing and dividing. Cells that are dividing most rapidly (such as cancer cells) are the most sensitive to radiation.

Why is radiotherapy used in conjunction with other treatments?

Once a cancer diagnosis has been made you may be referred for a radiation oncology opinion. Best cancer outcomes occur where patient care plans are determined through discussions between multi-disciplinary oncology specialists. For example, if you have breast cancer, you are likely to have breast cancer surgery to remove the tumour, radiotherapy to destroy any remaining cancer cells and possibly receive chemotherapy or hormone therapy to destroy cancer cells that may have travelled to other parts of the body.

How does radiotherapy work?

Radiotherapy is the use of radiation to safely and effectively treat cancer and other diseases. It may be used to cure cancer, control the growth of the cancer or relieve symptoms caused by cancer such as pain. Radiotherapy works by damaging cells. Normal cells are able to repair themselves, whereas cancer cells are less capable of repair. It is this difference that provides a biological advantage, which is used in planning radiotherapy treatments for different cancer types. To best harness this biological advantage radiotherapy is delivered usually in daily intervals, (Monday to Friday) called fractions. This allows time between daily treatments for the healthy cells to repair much of the radiation effect, while cancer cells are not as likely to survive.

Radiation oncologists optimise the radiation dose to treat the cancer using a tumoricidal dose, while at the same time minimising (where possible avoiding) radiation dose to healthy organs and tissues surrounding the cancer. Sometimes radiotherapy is the only treatment a patient needs, at other times, it forms one part of a patient's multifaceted treatment regimen. For example, prostate and larynx cancers are often treated with radiotherapy alone, whereas a breast cancer may be treated with surgery, radiotherapy and chemotherapy. Radiotherapy can increase the effectiveness of other treatments. For example, you can be treated with radiotherapy before surgery to help shrink a cancer and allow less extensive surgery than would otherwise have been needed. Or, you may be treated with radiation after surgery to destroy small amounts of microscopic cancer cells that may have been left behind.

What are the different types of radiation used?

Radiotherapy can be delivered in two ways: externally and internally.

During external beam radiotherapy, the radiation oncology team uses a machine called a Linear Accelerator (Linac) to direct high-energy X-rays at the cancer. This process is non-invasive and the majority of patients do not experience any sensation whilst receiving it.
Internal radiotherapy or brachytherapy involves placing radioactive sources (radioactive seeds) inside your body.

What is External Beam Radiotherapy?

During external beam radiotherapy radiation is directed using an individualised number of radiation beams through the skin to the cancer and the immediate surrounding area in order to destroy the tumour and any nearby cancer cells.

What is Brachytherapy?

Brachytherapy involves placing radioactive material into a tumour and its surrounding tissue by using either a high-dose or lose-dose method. Referred patients with prostate cancer may be able to have their treatment delivered using either approach. The radioactive sources used in low-dose prostate brachytherapy, come as implantable 'seeds'. These are implanted permanently into the prostate gland and remain in the body after the sources are no longer radioactive.

How is radiation generated?

The radiation is generated by a machine called a Linear Accelerator-also known as a Linac, which converts electricity into radiation. The Linac is capable of producing high-energy X-rays in a variety of different energies for the treatment best suited for your cancer. Using advanced treatment planning software, we are able to control the size and shape of the radiation beams and direct them at your body to effectively treat your tumour whilst sparing the surrounding normal tissue.

Is Radiotherapy safe?

Radiation has been used successfully to treat patients for more than 110 years. In that time, many advances have been made to ensure that radiotherapy is both safe and effective. We align treatment schedules and practices with current evidence based approaches. Your radiation oncologist will be able to explain the measures taken to ensure a safe reliable radiation dose delivery schedule for your situation.

Will I become radioactive after external beam radiotherapy?

No. Radiation is only present when being directed at the area of treatment whilst the machine is switched on. No radiation is left inside your body after the treatment: you will not be radioactive.

Will I lose my hair?

Temporary or permanent hair loss in the treated areas may occur. In the instance of radiotherapy hair will only fall out in the area of the body being treated. For example, if you are having radiotherapy to your head you will probably lose some hair from your scalp. If the area being treated includes an armpit or your chest, then it is only hair in these regions which is likely to fall out. This is a common side effect which can be discussed with your radiation oncologist.

Will radiotherapy hurt?

No. Radiotherapy is painless. During treatment, the majority of patients will experience no sensation and will only hear the sound of the treatment machine buzzing whilst it is switched on.

Will radiotherapy burn me?

After some weeks into your treatment, the skin and other tissues in the body react to the radiation, by becoming irritated and unpleasant. This is not a burn, but the body's inflammatory response to the radiation, the severity of which is dependent on the area of the body being treated, your general health and wellbeing, any medications or medical treatments you may be undergoing at the same time and the radiation dose prescribed. Your radiation oncologist will explain the likely severity of side effects in your case and ensure you are best prepared to manage them if they eventuate. Our nursing staff and radiation therapists are able to give you practical advice on how to manage this reaction throughout your treatment.

Will I be sick and sore from day one?

Not usually. Radiotherapy has a cumulative effect. As a general rule it will take some time for any side effects to develop. Similarly it takes some weeks after the completion of treatment before they start to subside.

Will radiotherapy make me sick?

Radiotherapy treatment only directly causes nausea and vomiting when treatment is being delivered to the abdominal region. Antiemetic medications are prescribed in these circumstances and can be very effective in controlling nausea caused by radiotherapy. The nursing staff can also advise on simple dietary and lifestyle adaptations that can help manage nausea alongside taking prescribed medication. Your radiation oncologist will discuss with you the likelihood of such side effects being experienced.

What is cancer?

Cancer is a generic name given to a group of diseases that involve uncontrolled multiplication of abnormal cells. This usually results in the area growing in size, affecting the original and adjacent organs and often results in the spread of the cancer to other sites of the body.

Some growths (tumours) are benign while others are malignant. Cancers are malignant growths. Benign tumours do not spread but they may cause a lump or put pressure on parts of the body near the tumour. They are often cured by surgical removal. Occasionally, radiation treatment may be given to contain the area of the tumour or reduce the risk of the tumour coming back.

Malignant tumours (cancer) are usually more active than benign tumours and tend to spread and invade other tissues. The original cancer site is called the primary tumour. If the cancer spreads to other organs or tissues, the cancerous areas are known as secondary tumours. Under the microscope, secondary cancers usually appear the same as the cells at the primary site, even though they appear elsewhere in the body.

Malignant tumours may be 'solid' or 'liquid'. 'Liquid' cancers are those involving the blood, such as leukaemia. Solid tumours may arise from any organ. In Australia, the most common cancers are breast cancer, bowel cancer, and melanoma (skin cancer) in females. In males, prostate cancer is the most common, followed by bowel cancer then melanoma (skin cancer).

Who are the members of the radiotherapy team?

Radiation Oncologists
Radiation Therapists
Medical Physicists
Radiation Oncology Nurses
Reception and Administration Staff
Read more detail about our staff and their role in your treatment

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GenesisCare is largest provider of radiation oncology in Australia, the UK and Spain, and also the leading provider of cardiology and sleep treatments in Australia. We exist to fill the treatment gap for the biggest disease burdens – cancer and heart disease – in an environment of substantial unmet demand from an ageing population. Click here to learn more