Brachytherapy is an advanced cancer treatment that delivers a highly concentrated dose of radiation near or in the tumor, while sparing the surrounding healthy tissue. Brachytherapy is localized, precise and high-tech: radioactive seeds or wires are placed in or near the tumor itself. For that reason, brachytherapy is also called a “radiation implant” or “radioactive source.”

The dose of radiation (number of seeds) and length of time prescribed will depend on the tumor size, location and sensitivity to radiation.

With high-dose rate (HDR) brachytherapy, thin catheters are first placed in the tumor. The catheters are then connected to an HDR afterloader. This machine contains a single highly radioactive iridium pellet at the end of a wire. The seed is pushed into each of the catheters one by one under computer control.

The computer controls how long the seed stays in each catheter (dwell time) and where along the catheter it should pause to release its radiation (dwell positions). With a few well-placed catheters in the tumor, HDR brachytherapy can provide a very precise treatment that takes only a few minutes. After a series of treatments, the catheters are removed, and there are no radioactive seeds left in the body.

Brachytherapy may be used alone or in combination with external beam radiation and/or surgery. It may cure, control or relieve symptoms of many different types of cancer. Some of the tumors Northwestern Medicine specialists treat with brachytherapy are:

• Prostate cancer
• Breast cancer
• Lung cancer
• Esophageal cancer
• Gynecologic cancers
• Anal/rectal cancers
• Sarcomas