People who have cancer (malignant tumor) generally have three treatment options: surgery, chemotherapy and radiotherapy. Radiotherapy, also called radiation therapy, aims to destroy the cancer tissue by exposing it to certain high-energy rays. The source of radiation can be located outside the body (external radiotherapy) as well as inside the body and very close to the tumor (internal radiotherapy or brachytherapy).

What is brachytherapy?

In brachytherapy the radioactive source is either placed very close to the tumor or directly into the tumor. In this approach the rays only have a short distance to travel in the body. The Greek word for “short” is brachys, and this is where the word “brachytherapy” comes from. Radioactive substances are used as the source of radiation for internal radiotherapy.

The aim of using radiotherapy in malignant tumors is to destroy the cancer cells, while at the same time trying to limit the damage to the surrounding healthy tissue. This is one of the main goals of brachytherapy, in which radioactive materials are implanted directly into or near the tumor during a small operation. Unlike external radiotherapy, radiation can reach the tumor directly, thereby minimizing the damage done to healthy tissue. Doctors are still trying out different types of radiotherapy in order to find out which approach is suitable for different people and situations.

When is brachytherapy used?

Whether or not a cancer is treated with radiotherapy, and brachytherapy in particular, depends on numerous factors: Where is the tumor? How big is it? Has it spread to other parts of the body? If so, to what extent? What kind of tumor is it (for example, what kind of cells is it made up of)?

Brachytherapy can be used in many parts of the body. There are three main types of brachytherapy which differ in terms of where and how the source of radiation is positioned:

  • Surface brachytherapy: The source of radiation is placed directly on the skin, for example in the treatment of skin cancer.
  • Intracavitary brachytherapy: The source of radiation is placed inside a natural cavity of the body, such as the womb, vagina, food pipe or the (airways).
  • Interstitial brachytherapy: In this type of brachytherapy, the source of radiation is placed directly into the tissue, for example in the prostate gland or breast. There are two options: The radioactive material is placed in the tissue and left there permanently (implanted) in small containers – capsules about the size of a grain of rice (seeds). It remains there, and the radiation decreases over the course of several months. Or the source of radiation is repeatedly inserted and removed over shorter time periods. Surgery is usually not necessary to do this.

How do doctors get the source of radiation inside the body?

The process of placing radioactive material inside the body usually involves several steps. First of all, one or several applicators are inserted. These might be thin tubes (catheters or cannulas) made of metal or plastic.

The doctor will then check whether they are in the right place using X-rays, ultrasound, or magnetic resonance tomography scans. If this is the case, the radiation source is placed in the body.

In an afterloading procedure, the radioactive source is put in place using a kind of robot. Here the person lies alone in a radiation-proof room but can talk to the doctors and nurses through a microphone. They may need to double-check the person’s position. This has the advantage of keeping medical staff from coming into direct contact with the source of radiation.

How long do you have to stay in the hospital?

The brachytherapy procedure can either be done as an outpatient service, so that you can go home on the same day, or with inpatient care and you stay in the hospital for a few days.

How often and for how long the radioactive source is inserted when using an afterloading technique depends on the type of tumor, among other things. The sessions might be spread out over one or several weeks. You usually do not have to stay in the hospital between sessions. The radioactive source is usually taken out again after a short time. In rare cases the radioactive source needs to be left in your body for several hours or even days. Then you will have to stay in the hospital for the whole duration of treatment.

What about the side effects of brachytherapy?

The affected area might be sensitive or sore for a while following treatment. Most people can return to their usual daily activities after only a few days. According to current knowledge, severe side effects following brachytherapy are rare. However, there has not been enough conclusive research to know exactly what effects this treatment might have in the long term.

If you experience problems during or following therapy, you can talk to your doctor about what you can do to relieve them.

What should I be aware of following the treatment?

In the kind of brachytherapy where the radioactive material is only temporarily inserted, no radiation is given off in the breaks between treatment and after the treatment is finished. There is no need to take any special safety precautions when you are around other people during this time. Even if a radioactive source is implanted permanently, in most cases the amount of radiation that escapes from the body is minimal because the types of rays used do not travel very far – just a few centimeters.

However, with some forms of treatment, radiation may be emitted from your body for some time. If this is the case, you might have to stay for a while in a special hospital ward that will take protective measures.

As with any other kind of radiotherapy, it may take weeks or months before you see a result.

Andreae S. Lexikon der Krankheiten und Untersuchungen. Stuttgart: Thieme; 2008.

Hoskin PJ, Bownes P. Innovative technologies in radiation therapy: brachytherapy. Semin Radiat Oncol 2006; 16(4): 209-217.

Pschyrembel W. Klinisches Wörterbuch. Berlin: De Gruyter; 2014.

The Swedish Council on Technology Assessment in Health Care (SBU). Radiotherapy for cancer: a systematic literature review. Stockholm: SBU. May 2003.

IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

Comment on this page

What would you like to share with us?

We welcome any feedback and ideas - either via our form or by We will review, but not publish, your ratings and comments. Your information will of course be treated confidentially. Fields marked with an asterisk (*) are required fields.

Please note that we do not provide individual advice on matters of health. You can read about where to find help and support in Germany in our information “How can I find self-help groups and information centers?

Print page

Über diese Seite

Updated on September 15, 2022

Next planned update: 2025


Institute for Quality and Efficiency in Health Care (IQWiG, Germany)

How we keep you informed

Follow us on Twitter or subscribe to our newsletter or newsfeed. You can find all of our films online on YouTube.