Understanding Radiation Therapy
Understanding Radiation Therapy
What is radiation therapy?
Radiation therapy, or radiotherapy, is a cancer treatment method which uses high-energy X-rays or other particles to kill the cancer cells.
How does radiation work?
As we know, each cell has a nucleus which contains the DNA responsible for cell division and growth. Contrary to what is commonly believed, radiation doesn't kill or burn the tumour cells. It damages the DNA of the cancer cells irreparably so that they do not multiply and grow further.
Is it painful?
No. Radiation therapy is a painless treatment. It uses high-energy X-rays, which are the same rays used in X-rays of bones or CT scans. Pain can occur due to disease itself or some side effects, but radiation itself is painless.
Where can radiation be used?
Radiation is an integral part of cancer treatment. It has a role in almost all cancers. It can be used alone, as in most head and neck cancers and brain tumours, with or without chemotherapy, after surgery as additional treatment, as in breast cancer or as a palliative treatment to treat the symptoms like bone soon, bleeding or brain metastasis in the last stage of cancer. It is a local treatment at the site of the disease and doesn't affect other parts of the body. Use of radiation depends on the cancer type, location, stage, patient's age and general condition.
Are there any side effects of Radiation therapy?
Yes, Radiation does cause some side effects. Whenever radiation enters your body, part of it is absorbed, and the rest then exits the body. So it is going to affect all the organs and tissues it passes through. With various technological advances in radiation techniques over the years, it is planned in such a way that it causes maximum damage to the cancer cells and minimum to the surrounding normal tissues. The damage to these normal tissues is known as the side effects. It depends on the site of treatment and will be confined to the nearby structures only and not affect the whole body. Like if you are getting treatment in the head and neck region, you might get some oral ulcers, difficulty in swallowing, skin darkening, etc, for radiation in the abdomen, you might have mild abdominal pain or burning in passing urine or stools. Since your doctor knows what the nearby areas are affected, the side effects can be easily predicted, for which your doctor will prescribe medications preventively, and they can be easily managed. The rationale behind giving radiation for five days with a two-day gap is to let the normal tissues repair and recover in the gap period, while the cancer cells cannot. Also, as soon as your radiation stops, it will heal and be back to normal in a few days.
What are the types of Radiation therapy?
There are mainly two types of radiotherapy
- External beam radiotherapy/teletherapy: Here, a large machine generates rays which are then directed to the patient's body from different directions to the specified area from a distance without touching the patient.
- Internal beam radiotherapy/brachytherapy: Here, the radiation source is placed inside the patient's body in close proximity to the tumour. It gives radiation very close to the tumour, causing the least damage to surrounding tissues.
The choice of these treatments depends on a lot of factors, like the type and stage of the tumour, and can be used alone or in combination.
What are the different techniques of Radiation therapy?
Radiation therapy delivery techniques have shown considerable advances in the last few years. The aim is to treat the disease precisely and accurately with minimum damage to surrounding areas. Some of these techniques are Intensity modulated radiotherapy (IMRT), Image guided radiotherapy ( IGRT), Volumetric arc therapy ( VMAT), Stereotactic radiosurgery (SRS), Stereotactic body Radiotherapy (SBRT ), Deep inspiration breath hold (DIBH). You should always discuss with your doctor about the techniques available and best suited for your disease.
