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List of terms beginning with Ra


Radiation means giving off any energy particles or waves. In cancer it means radioactivity used as a treatment. This means gamma rays, alpha or beta particles from a radioactive source.

Radical cystectomy

Radical cystectomy is an operation to remove the bladder and nearby lymph nodes. In men the prostate gland is also removed. In women the womb and ovaries may also be removed.

Radical gallbladder resection

Radical gallbladder resection is an operation to take out the gallbladder, a small part of the liver, the common bile duct, and the nearby lymph nodes. It may also involve taking out part or all of your pancreas, liver, or bowel.

Radical hysterectomy

Radical hysterectomy is an operation to remove the womb. During the surgery the surgeon removes the womb, all the tissues holding the womb in place, and the lymph nodes around the womb.

Radical mastectomy

Radical mastectomy is an operation to remove the breast, the lymph glands under the arm and the muscles of the chest wall.

Radical radiotherapy

Radical radiotherapy is an intensive course of radiotherapy given to try to cure a cancer.

Radical surgery

Radical surgery is a type of extensive surgery which aims to remove all possible body tissue that could be affected by a particular cancer.

Radical trachelectomy

Radical trachelectomy is an operation to remove early cancer of the cervix (the neck of the womb). The surgeon removes most of your cervix, but leaves some behind. This is then stitched closed to leave a small opening. You may also have the upper part of the vagina, the area around the lower part of the womb and the pelvic lymph nodes removed. After this operation you may still be able to become pregnant. It is not a suitable operation for all women with cervical cancer.

Radical treatment

Radical treatment aims to completely get rid of a cancer.


A substance or object that gives off high energy rays or particles is known as radioactive.

Radioactive beads

Radioactive beads are used in some internal radiotherapy treatments. The beads are made of isotopes of gold or iodine and give off radiation. The beads are put inside the body close to the area of the cancer. This gives a high dose of radiotherapy to the cancer, but a low dose to healthy parts of the body.

Radioactive drink

Radioactive drink is a type of internal radiotherapy given in liquid form as a drink. For example, radioactive iodine to treat cancer of the thyroid.

Radioactive dye

Radioactive dye is a type of dye which gives off a small amount of radiation. It is used during some types of scan.

Radioactive injection

A radioactive injection is a tiny amount of a radioactive substance given into a vein. This is usually done for a scan, such as a bone scan. But it can also be used to give cancer treatments, such as radioactive phosphorous (P32).

Radioactive liquid

Radioactive liquid is a liquid that gives off radiation.

Radioactive material

A radioactive material is any substance which gives off radiation.

Radioactive source

A radioactive source (or radiation source) is a substance or object that gives off radiation. Radiotherapy machines contain radioactive sources. Internal radiotherapy may use radioactive implants, wires, or small metal balls as the source.


Radioembolisation means cutting off the blood supply to a cancer by using a radioactive material to block the blood vessels. This reduces the amount of nutrients and oxygen getting to the cancer and can shrink it.

Radiofrequency ablation

A type of treatment using heat from radiowaves to kill cancer cells. Radiofrequency is a type of electrical energy, which heats up the tumour and kills the cancer cells.


A radiographer is a person trained to give radiotherapy treatment and take X-rays. Therapy radiographers give radiotherapy treatment. Diagnostic radiographers take X-rays to diagnose illness.


A radiologist is a doctor who specialises in reading X-rays and scans, and carrying out scans and other specialist X-ray techniques.


A radionuclide is a radioactive form of an atom. Some are natural and some are man made. They can be used in tiny amounts to create pictures in a bone scan, for example. Or they may be used as a cancer treatment. Iodine 131 is an example of a radionuclide and is a radioactive form of iodine.

Radionuclide therapy

Radionuclide therapy is a type of internal radiotherapy using a radioactive liquid. The liquid circulates throughout the body and targets particular types of cells.


Radiosensitising means a drug or substance that increases sensitivity to radiation. For example, some cancer drugs make radiotherapy work better so they are given with radiotherapy to treat some types of cancer.


A cancer that responds well to radiotherapy is said to be radiosensitive.


A radiotherapist is a doctor who specialises in treating patients with radiotherapy. The term is not commonly used these days. Radiotherapy doctors are now called clinical oncologists.


A type of cancer treatment that uses high energy waves similar to X-rays to kill cancer cells.

Radiotherapy department

The hospital department where radiotherapy treatment is planned and given is called a radiotherapy department.

Radiotherapy field

A radiotherapy field is the area of the body that is treated with radiotherapy. Usually several beams are used for external radiotherapy, and they overlap at the area of the cancer.

Radiotherapy implant

A radiotherapy implant (or radioactive implant) is a radioactive substance put inside the body to give radiotherapy directly to a cancer. It can be used in many different forms, such as wires or small metal beads. For example, irridium wires can be put into the breast or tongue to treat breast cancer or mouth cancer.

Radiotherapy limit

A radiotherapy limit is the maximum amount of radiotherapy that can be given to a part of the body, or to any one person. Each body organ has its own radiotherapy limit. Some organs are more sensitive to radiotherapy than others.

Radiotherapy machine

A radiotherapy machine is used to give external radiotherapy treatment for cancer (and some other illnesses and conditions).

Radiotherapy nurse

A radiotherapy nurse works in the radiotherapy department and can advise patients about managing radiotherapy treatment and side effects.

Radiotherapy planning

Radiotherapy planning is the process of designing a person's course of radiotherapy treatment.

Radiotherapy side effects

Radiotherapy side effects are the unwanted effects on the body from radiotherapy. Radiotherapy can cause tiredness. Other side effects usually only occur in the area of the body being treated. The side effects don't usually begin as soon as you start the treatment. They take a while to build up and then slowly disappear a little while after you have finished the treatment. This may take a number of weeks.


Radium is a naturally occuring radioactive metal. It gives off radiation. Radium was the first radioactive substance used to treat cancer.

Radon gas

Radon is a naturally occuring radioactive gas given off by the earth. The amount varies across the UK. Areas with a lot of granite in the ground tend to have higher than average levels of radon. In the UK this includes Derbyshire, Devon, Cornwall, Somerset and Northamptonshire. Radon is one of the causes of lung cancer and may contribute to causing other cancers as well.


Random is when something happens by chance.


In clinical trials, randomisation is the process of putting people into groups by chance, to make sure there is no bias.

Randomised controlled trial

A randomised controlled trial is where people are put into groups by chance. One group is given the best current treatment or a placebo and their progress is compared to people having the treatment that is being tested. People are usually selected for each group by a computer.

Randomised trial

A clinical trial which compares different treatments to find out which works best is known as a randomised trial. People taking part are put into the different trial groups by a computer.

Updated: 29 June 2016