Brachytherapy

What Is Brachytherapy?

Brachytherapy is a unique form of radiation therapy. Brachy means short or close and refers to the short distance between the radiation source and the tumor. In contrast to the usual external radiation therapy, the radioactive radiation source is placed directly on or inside the tumor, which enables targeted irradiation of the tumor area and offers the best possible protection of the surrounding healthy body tissue. Depending on the indication, brachytherapy can be considered as sole radiotherapy or in combination with external radiation.

In brachytherapy, as in almost all forms of radiation therapy, gamma rays are used, which are produced during the natural decay of atomic nuclei. The radioactive radiation released during this process leads to damage or even death of body cells. The extremely rapid growth of many tumor cells makes them more susceptible to radiation than the surrounding tissue.

Nevertheless, healthy body cells can also be damaged during treatment. Particularly with external radiation, the radiation passes through several layers of body tissue. Brachytherapy attempts to avoid this.

Which Brachytherapy Procedures Are Available?

There are two forms of brachytherapy: interstitial and intraluminal brachytherapy.

Interstitial brachytherapy

In interstitial brachytherapy, the radioactive radiation sources are introduced directly into the organ in question. These radiation sources are also called seeds (as in seeds planted in soil). They are mainly used for prostate cancer, where they remain permanently in the organ after insertion and act on the tumor tissue.

Intraluminal brachytherapy

In intraluminal brachytherapy, the radiation source is applied via the applicator into the cavity surrounding the tumor (e.g., trachea/esophagus), which is done for the respective period of treatment (minutes) and removed afterward.

For Which Types of Cancer can Brachytherapy Be Used?

In principle, due to the type of radiation application, the best treatment can be carried out on regions of the body that are accessible from the outside. Therefore, the following types of cancer are mainly treated with brachytherapy radiation:

• Prostate cancer
• Cervical cancer
• Breast Cancer
• Skin cancer

But also, cancer diseases of other body regions can be treated by brachytherapy. These include:

• Rectal cancer
• Tumors of the esophagus
• Tumors of the trachea and bronchia
• Urinary tract tumors
• Head and neck tumors
• Brain tumors
• Eye tumors

The radiation source can be administered into the body during therapy via the respective body orifice so that direct contact with the tumor can be established. This reduces the radiation dose and shortens the duration of the treatment. An additional advantage is that the procedure is not necessarily carried out in a hospital. Due to the less frequent therapy sessions, outpatient brachytherapy is often also possible.

How Does Brachytherapy Irradiation Work?

Like any other type of radiotherapy, the therapy starts with planning the procedure. Certain information is required for this. A precise knowledge of the extent, type, and location of the tumor are essential. Therefore, various diagnostic procedures must be used at the beginning. These include X-rays, computed tomography, magnetic resonance imaging, and ultrasound.

With the help of the data obtained in radiology, modern data processing can produce three-dimensional images of the tumor with exact localization in the body. Individual programs can be used to plan the optimal distribution of radiation sources and calculate the doses that will hit the tumor and surrounding tissue.

By variability of the radiation positions, the best possible combination can be calculated to prevent so-called hot spots (areas with too high radiation doses) and cold spots (areas with too low radiation doses).

If this has been successful, the next step can be taken; inserting the applicators. The applicator is the delivery system for the radioactive substance that is later placed. With the help of the previously calculated image data, the exact position for the applicators in the body can be achieved, where they are fixed.

At the same time, the radiotherapist prepares a treatment plan. This plan includes, among others, how much radiation dose will be applied and for how long, and how many sessions will be necessary.

What Are the Advantages and Side Effects of Brachytherapy?

The less the surrounding tissue and the more the tumor is irradiated, the better, which is the advantage offered by brachytherapy. Unfortunately, this option is not available for all types of cancer, as access via the mouth, anus, vagina, or lying on the skin (in the case of skin cancer) is necessary. Focused irradiation also reduces the risk of recurrence (risk of the tumor reappearing).

Despite the precise irradiation of the tumor, radioactive radiation always causes side effects. For example, during treatment, swelling, bleeding, discharge, difficulty urinating, diarrhea, and skin flaking or irritation may occur. During this time, medication can help to relieve these symptoms. Most side effects subside after 4-8 weeks after the treatment when the body cells have had time to regenerate.

In rare cases, there may also be permanent dysfunction of the digestive organs (diarrhea) or the bladder. Scarring can also occur when the breast or skin is irradiated, which makes follow-up treatment necessary.

No special precautions need to be taken regarding the seeds. The range of the radiation is limited to the organ. Thus, fellow human beings are not exposed to any additional radiation dose.

If the brachytherapy is successful, follow-up examinations follow at specified intervals. These serve to check the long-term therapy success and enable detection of a recurrence of the tumor as early as possible.

Brachytherapy Cost Absorption

The question of whether brachytherapy is generally covered by health insurance or has to be paid for by the patient cannot be definitely answered since it depends on the type of cancer to be irradiated, whether the patient participates in a study, and if the treating physicians recommend brachytherapy. Two examples show the different ways in which health insurance companies handle the assumption of costs.

Cost Absorption of Brachytherapy for Prostate Cancer

Brachytherapy for prostate cancer is carried out by seed implantation or after loading. Since studies have not proven the effectiveness of brachytherapy in comparison to other treatment methods, the acceptance of the cost by the health insurance company should be clarified in advance.

Cost Absorption of Brachytherapy for Cervical Cancer

Brachytherapy is an established procedure for cervical cancer. If the treating physicians recommend brachytherapy, the costs are covered by the health insurance companies.

It is therefore advisable to enquire with the treating physicians and the health insurance company about the cost acceptance of brachytherapy in advance.

Sources:

• www.radioonkologie.insel.ch/de/unser-angebot/zentrum-fuer-brachytherapie/
• de.wikipedia.org/wiki/Brachytherapie