What is brachytherapy?

What is brachytherapy and how it works

Brachytherapy is an internal radiation therapy used for cancer treatment. Seeds, pallets, wires, capsules or catheter that contain the radioactive material are placed inside a body or near the tumor before the procedure. The radiation beams directly to the cancer cells and damages their DNA. The Radiation can either damage DNA directly or create charged particles, called free radicals, within the cells that can in turn damage the DNA. Iodine-125 is the most commonly used isotope for the brachytherapy.

The types of brachytherapy

There are three types of the brachytherapy:

· Low-dose rate (LDR): implant with radiation source stays in the body for one to seven days and continuously releases low doses of radiation.

· High-dose rate (HDR): implant with radiation source remains in the body for 10 to 20 minutes and is removed after the procedure. The treatment may take place twice a day for two to five days or once a week for two to five weeks.

· Permanent (seed implantation): implants or seeds remain in the body permanently. They release radiation continually, but the radiation gets weaker every day.

The techniques used

There are three types of techniques that can be used to perform brachytherapy:

· Intracavity brachytherapy: the radiation source is placed inside a body, near the tumor

· Interstitial brachytherapy: the radiation source is placed within the tumor

· Episcleral brachytherapy: the radiation source is attached to the eyeball

Brachytherapy can be used to treat these kinds of cancer:

Breast

Cervix

Eye

Head and neck

Brain

Lung