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Radiotherapy

Radiotherapy

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Radiotherapy is a form of treatment for cancer that uses ionizing radiation. Despite the fact that ionizing radiation can be harmful, it can also be used to fight cancer. This article will explain how and why radiation therapy is used in cancer treatment, the different types of radiotherapy, and the effects it can have on the body.

Radiotherapy treatment

Radiation therapy or radiotherapy is a treatment for cancer that involves killing the cancer-causing cells using high doses of radiation. The type of radiation used can vary depending on the type of cancer that is being treated. Radiation therapy can be administered in two ways. External beam radiation therapy and internal radiation therapy. Overexposure to X-ray machines can damage the DNA in the cells leading to cancer. This is why doctors place a limit on the number of X-rays a patient is exposed to. X-ray machines produce low-powered X-rays that can damage the body in large doses. A single X-ray will not expose the body to any harm but the people who operate X-rays machines need to exercise precautions to limit their exposure to these rays.

External beam radiation therapy

External beam radiation is produced by a machine that directs the ionizing radiation at the cancer cells. The machine will be able to move around the person undergoing treatment. It treats a specific part of the body. For example, radiotherapy for breast cancer consists of directing radiation only towards the region between the neck and the abdomen.

Internal radiation therapy

Internal radiation is when the source of radiation is placed inside the body of a person undergoing treatment. The radiation source can be a capsule which is then placed close to the tumour in the body. This means that the tumour will be exposed directly to the highest intensity dose of radiation.

How does it work?

So then how does radiation therapy stop the spread of cancer? Radiation therapy makes use of high-energy beams of gamma rays to destroy tumours. Unlike normal cells, cancer cells can multiply uncontrollably quickly. The ionizing radiation beams slow down the growth by breaking down the DNA of the cancer cells.

Radiation This is an example of a radiopharmaceutical used in internal radiotherapy treatments. Radioactive compounds are attached to 'targeting molecules' which can bind to 'target proteins' attached to cancer cells. cancer.gov

Normal cells that are exposed to the radiation are also damaged but can repair themselves to a certain extent. Cancer cells on the other hand do not have the ability to repair themselves after damage from radiation.

Lifetime dose limits define the maximum amount of radiation dosage a human body can receive in its lifetime. If a person has already received radiation therapy, they may not be able to receive this treatment again. different areas of the body can be treated given they have a great enough distance between them.

Radiotherapy machine

One of the most commonly used radiotherapy machines is called a Linear accelerator (LINAC). The linear accelerator converts electricity into high-energy X-rays or electron beams. The beams are then directed towards the patient's tumour.

Linear accelerator used for radiotherapy, Radiology Info

Linear accelerator used for radiotherapy, Radiology Info

It works by accelerating electrons towards a heavy metal target. This collision produces high-energy X-ray beams as they exit the machine. The patient is placed on a bed that is part of the machine. The beam exits out of a movable head that can rotate around the patient's bed. This allows radiation to be delivered to the desired body part.

Radiotherapy side effects

We've studied how radiation therapy can eliminate cancer cells. However, it is important to understand that ionizing radiations will ultimately also affect healthy cells around the tumour. The side effects can vary depending on the body part that is exposed to radiation. Some of the common side effects of radiation therapy are

Nausea Hair-loss Cough Shortness of breath Diarrhoea

Cells that are damaged from radiation therapy usually recover back to normal in a few months after treatment. But there is a possibility that the side effects do not reduce with time. Certain side effects may show up even months or years after radiation therapy. These side-effects are called late effects.

That brings us to the end of this article. Let's look at what we've learned so far.

Radiotherapy - Key takeaways Radiation therapy or radiotherapy is a treatment for cancer that involves killing the cancer-causing cells using high doses of radiation. Radiation therapy can be administered in two ways: external beam radiation therapy and internal radiation therapy. External beam radiation is produced by a machine that directs the ionizing radiation at the cancer cells. Internal radiation therapy is when the source of radiation is placed inside the body of a person undergoing treatment. One of the most commonly used radiotherapy machines is called a Linear accelerator (LINAC).Ionizing radiations also affect healthy cells around the tumour. Side effects can vary depending on the body part that is exposed to radiation. Some of the common side effects of radiation therapy include Nausea, Hair-loss, Cough, Shortness of breath, and Diarrhoea.

Radiotherapy

What is radiotherapy used for?

Radiotherapy or radiation therapy is used as a treatment for cancer by killing the cancer-causing cells using high doses of radiation.

What is the difference between radiotherapy and chemotherapy?

Chemotherapy uses drugs to reduce the size of the tumors. Radiation therapy uses high-energy X rays and electron beams to kill them.

How does radiotherapy work?

Radiotherapy works by using ionizing radiation beams to slow down the growth of tumors. They break down the DNA of the cancer cells resulting in killing them or stunting their growth. Normal cells that are exposed to the radiation are also damaged but can repair themselves to a certain extent. Cancer cells on the other hand do not have the ability to repair themselves after damage from radiation.

What is radiotherapy?

Radiotherapy or radiation therapy is a treatment for cancer that involves killing the cancer-causing cells using high doses of radiation.

What are the side effects of radiotherapy?

Common side effects of radiotherapy include:NauseaHair-lossCoughShortness of breathDiarrhoeaThe side effects can vary depending on the body part that is exposed to radiation.

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