Internal radiation therapy

During internal radiation therapy (IRT), radioactive material is placed into a catheter or another implantable device, which carries the radiation directly into or near a tumor. Implanting the device is generally painless, and the implants may be temporary or permanent. A variety of cancers may be treated with IRT (also referred to as brachytherapy), including prostate cancer, a variety of gynecologic cancers and, in rare cases, head and neck or other cancers.

Intraoperative radiation therapy (IORT) delivers a concentrated dose of radiation to the site of a tumor during surgery. IORT may help reduce side effects and the need for additional radiation treatments.

What is brachytherapy?

Brachytherapy allows for a precise treatment in only a few minutes. It offers a quicker, more effective type of radiation treatment for some patients than traditional radiation delivered in smaller doses over a longer period of time. For many cancer types, the entire brachytherapy treatment takes one to two days, instead of five to seven weeks for external beam radiation therapy (EBRT). Depending on the type and stage of cancer, brachytherapy may be combined with other treatments, which can vary treatment times.

Types of brachytherapy include:

High-dose rate (HDR) brachytherapy: This internal radiation therapy delivers a high-dose of radiation from implants placed close to, or inside, the tumor(s) in the body in a short burst lasting a few minutes. Before each treatment, we check the position of the catheters with millimeter precision. Next, a radioactive pellet is inserted into each catheter sequentially. Computer guidance controls how far the pellet goes into the catheter to precisely target the location of tumors, and how long the pellet stays in the catheter to release its radiation dose. With a few well-placed catheters, HDR brachytherapy can provide a precise treatment that takes only a few minutes. Brachytherapy offers a quicker, more effective type of radiation treatment for some patients. For many cancer types, the entire brachytherapy treatment takes one to two days, instead of five to seven weeks for EBRT.

Low-dose brachytherapy (LDR): Also sometimes called permanent seed implants, LDR brachytherapy uses radioactive seeds permanently implanted into the organ. These pellets emit low levels of radiation for several weeks. When this radiation treatment ends, the harmless seeds are left in place permanently. Primarily used to treat prostate cancer, LDR brachytherapy is a one-time procedure performed on an outpatient basis. The procedure itself generally takes about an hour. Brachytherapy offers a quicker type of radiation treatment for some patients. 

What is IORT?

With IORT, a radiation oncologist delivers a large dose of radiation in a single treatment session during a surgical procedure. A patient must be a surgical candidate to be eligible for IORT. This treatment is generally reserved for individuals with early-stage disease.

Advantages of IORT include:

Efficient dosing. IORT delivers a concentrated dose of radiation to a tumor site immediately after a tumor is removed, helping to destroy the microscopic tumor cells that may be left behind.

Helps spare healthy tissues and organs. During IORT, a radiation oncologist applies a precise radiation dose while shielding healthy tissues or structures, such as the skin, that may be damaged using other techniques.

Shortened treatment times. IORT may help reduce the need for additional radiation therapy, which is typically given over weeks.

A "boost" for traditional radiation patients. Patients who must receive radiation therapy after surgery may receive a boost of radiation during IORT, allowing more time to recover from surgery before continuing radiation therapy.