How does radiotherapy target cancer cells?

Radiotherapy targets cancer cells by directing high-energy radiation at the cancerous tissue to destroy or damage it.

Radiotherapy, also known as radiation therapy, is a common treatment for various types of cancer. It works by using high-energy radiation, such as X-rays, gamma rays, or charged particles, to target and destroy cancer cells. The radiation damages the DNA within these cells, preventing them from growing and dividing, which ultimately leads to their death.

The process of radiotherapy is carefully planned to ensure that the radiation is accurately targeted at the cancerous tissue. This is achieved through a process called 'treatment planning'. In this process, detailed scans of the patient's body are taken to determine the exact location, size and shape of the cancer. This information is then used to plan the direction and intensity of the radiation beams, ensuring they are precisely aimed at the cancer cells, while minimising damage to surrounding healthy tissue.

The radiation used in radiotherapy can be delivered in two main ways: externally or internally. External radiotherapy involves a machine directing the radiation at the cancer from outside the body. Internal radiotherapy, also known as brachytherapy, involves placing a radioactive material inside the body, near the cancer.

Radiotherapy is often used in combination with other treatments, such as surgery or chemotherapy, to increase its effectiveness. It can also be used to relieve symptoms in advanced cancers. Despite its effectiveness, radiotherapy does have side effects, which can include fatigue, skin reactions, and other symptoms depending on the area of the body being treated. These side effects are usually temporary and can be managed with the help of the healthcare team.

In summary, radiotherapy targets cancer cells by directing high-energy radiation at them, damaging their DNA and preventing them from growing and dividing. The treatment is carefully planned to ensure the radiation is accurately targeted, minimising damage to healthy tissue.