Intraoperative radiation therapy (IORT) is an experimental way to give radiation therapy. In IORT, the radiation is delivered directly to the area where the breast cancer was during surgery to remove the cancer. The TARGIT study found that IORT and traditional external beam radiation therapy offer similar cosmetic results. The findings were presented at the 2009 ASCO Breast Cancer Symposium.
The TARGIT study is comparing IORT to radiation therapy delivered by external beam (the traditional way to give radiation therapy) after lumpectomy. The TARGIT researchers want to know if IORT is as good as or better than traditional external beam radiation therapy in reducing the risk of breast cancer coming back (recurrence).
If IORT is found to be safe and effective, it could be a desirable alternative to traditional radiation therapy. IORT radiation is very focused, so surrounding healthy tissue isn't exposed to radiation. Traditional external beam radiation has a wider field and may expose healthy tissue, such as the heart and lungs, to radiation. Still, recent external beam radiation therapy techniques help minimize this problem. Also, IORT delivers the entire radiation dose in one treatment. So IORT might allow people to avoid weeks of daily trips to the hospital to receive traditional external beam radiation therapy treatments.
Because IORT delivers the entire radiation treatment at one time, the researchers wanted to see if IORT slowed wound healing after surgery, which might lead to a less desirable cosmetic result. The researchers compared the cosmetic outcomes of 105 women diagnosed with early-stage breast cancer and treated with lumpectomy and IORT in the TARGIT study to the cosmetic outcomes of similar women who received standard external beam radiation after lumpectomy. The researchers used a special computer program that analyzed digital photos of the breast area 2 and 3 years after surgery. The software evaluated the cosmetic appearance of the breast, including scarring, color changes, and balance (compared to the opposite breast).
After 2 years:
- 78% of women who had IORT were judged to have an excellent cosmetic outcome, compared to 74% of women who had external beam radiation therapy
- 21.8% of women who had IORT were judged to have a fair or poor cosmetic outcome, compared to 26% of women who had external beam radiation therapy
After 3 years:
- The percentages of women in both groups who had excellent cosmetic outcomes were still about equal
- 13.8% of women who had IORT were judged to have a fair or a poor cosmetic outcome, compared to 30% of women who had external beam radiation therapy
It will be some time before researchers can fully compare the benefits of IORT to traditional external beam radiation. If IORT has similar risk reduction and cosmetic benefits, the limited radiation exposure and convenience of one treatment could make IORT a very attractive radiation therapy option in the future.
While IORT is still experimental, there are several approved alternatives to traditional external beam radiation therapy that deliver more focused radiation therapy over a shorter period of time, including:
- two forms of internal radiation therapy (brachytherapy):
- multi-catheter internal radiation
- balloon internal radiation (brand name: MammoSite)
- 3-D conformal external beam radiation
You can learn more about radiation therapy options in the Breastcancer.org Radiation Therapy section.