After lumpectomy to remove early-stage breast cancer, radiation therapy commonly is given to reduce the risk of the cancer coming back (recurrence). Lumpectomy and radiation are a good alternative to mastectomy.
The study reviewed here found that three alternatives to traditional external beam radiation therapy are all equally effective at lowering the risk of recurrence and offer the same benefits as traditional radiation therapy. The results were presented at the 2009 ASCO Breast Cancer Symposium.
Traditional external beam radiation therapy aims cancer-destroying energy at the whole breast or to the area of the breast where the cancer was. The radiation source for external beam therapy is outside the breast, which is what makes it "external." Drawbacks of traditional radiation therapy include daily trips to the hospital for treatments (typically 5 days a week for 4 to 6 weeks) and unintended exposure of nearby healthy tissue (lungs or heart, example) to radiation.
To overcome the drawbacks of traditional radiation therapy, doctors have developed different ways to deliver radiation. These new techniques are called "accelerated partial breast irradiation." The new techniques deliver more focused and intense radiation therapy over a shorter period of time. Because the radiation is more focused, the new techniques may cause fewer or milder side effects than traditional radiation therapy.
The three accelerated partial breast irradiation techniques evaluated in this study are:
Multi-catheter internal radiation uses radioactive "seeds" to deliver radiation directly to the area where the cancer was. The seeds are placed in very small tubes (catheters) that are stitched into place under the skin. The seeds are left in the catheters for a few hours or a few days. You remain in the hospital during treatment. Once the treatment is completed, the seeds, catheters, and stitches are removed and you go home. (199 women received this type of radiation.)
Balloon internal radiation places a special catheter with a balloon on the end in the place in the breast where the cancer was. The catheter, which comes out of the skin, and balloon are placed either during lumpectomy or afterward, in a surgeon's office. For each treatment, a machine places a radioactive seed into the center of the balloon for up to 10 minutes. After the seed is removed, you're free to leave the treatment center between treatments. Treatments are usually given twice per day for 5 days. When the final treatment is done, the balloon and catheter are removed. (80 women received this type of radiation.)
3-D conformal external beam radiation uses 3-dimensional CAT scan or MRI imaging before radiation therapy to plan more precise delivery in three dimensions of more intense radiation. Because each treatment delivers more intense radiation in a more focused way (compared to traditional radiation therapy), treatment may be completed in 1 week. (94 women received this type of radiation.)
Five years after diagnosis, the researchers compared the treatment outcomes of the three types of accelerated partial breast irradiation and found no real differences:
These differences were small enough to have happened by chance, not because of the different irradiation techniques.
Cosmetic outcomes also were good. The three types of accelerated partial breast irradiation had similar percentages of women who were judged to have good to excellent results, ranging from 89% (3-D conformal radiation) to 99% (brachytherapy).
While these results are promising, more research is needed. More follow-up (longer than 5 years for each technique) is needed before doctors can conclude with confidence that these techniques are comparable to each other and to traditional external beam radiation therapy. While there are more than 10 years of follow-up study on women who received brachytherapy, the follow-up periods for the other two groups are closer to 5 years.
If you've been diagnosed with early-stage breast cancer and lumpectomy followed by radiation therapy will be part of your treatment, ask your doctor about the radiation therapy options that make the most sense for you. Things you'll likely consider include:
Together you and your doctor will make the best choice for you and your unique situation.
Visit the Breastcancer.org Radiation Therapy section to learn more about all radiation therapy techniques.
SAN FRANCISCO (MedPage Today) -- All three variations of accelerated partial breast irradiation appear to have promising and similar outcomes in early stage breast cancer, according to results from a center that pioneered the treatment in the United States.
Brachytherapy, 3-D conformal external beam radiation, and MammoSite yielded overall survival rates of 89%, 87%, and 92%, respectively, at five years, Peter Y. Chen, of William Beaumont Hospital in Royal Oak, Mich., and colleagues reported here at the ASCO Breast Cancer Symposium.
Local control at five years with the partial irradiation strategies was in the same 1% to 2% range seen with conventional whole breast radiotherapy, commented Eleanor Harris, MD, of the Moffitt Cancer Center in Tampa, Fla. co-chair of the session at which the findings were discussed.
"It's reassuring that when you do apply these very strict selection criteria, that the outcomes do look promising," she said.
However, Harris cautioned that while patients are increasingly demanding these more convenient radiation approaches, all professional societies with guidelines on use have recommended warning patients that accelerated partial breast irradiation is not standard of care.
Part of the concern is a relatively short follow-up, added Stephen Edge, MD, of the Roswell Park Cancer Institute in Buffalo, New York, who with co-chaired the session with Harris.
"We're in a dilemma right now," he said. "People are applying these technologies, but there is not long term evidence. The trials are not mature."
So Chen's group examined their institution's experience, which is among the longest in the nation. They looked at outcomes from the 373 patients treated with one of the three forms of accelerated partial breast irradiation from 1993 through 2006:
Eligibility criteria included age over 40, diagnosis of invasive ductal carcinoma of at least 3 cm, lobular carcinoma or ductal carcinoma in situ, partial mastectomy with negative margins, and no negative nodes, skin involvement, or Paget's disease.
At five years, actuarial outcome rates with brachytherapy, 3-D conformal radiation, and MammoSite, respectively, were:
These rates were comparable to previously published results for all three, Chen noted.
Cosmesis was good to excellent in nearly all patients as well: 99% with brachytherapy, 89% with 3-D conformal therapy, and 94% with MammoSite.
Although the brachytherapy patients averaged nearly 10 years of follow-up, the other accelerated partial breast irradiation methods need continued follow-up to determine long-term efficacy and equivalence, Chen cautioned.
He noted that class I evidence is maturing in five phase III trials, with one in high-risk patients.
The researchers reported conflicts of interest with Hologic for MammoSite.
Harris reported serving in an advisory or consultancy role with Calypso. Edge reported no conflicts of interest.
Primary source: ASCO Breast Cancer Symposium Source reference: Chen PY, et al "Comparative efficacy analysis of three forms of accelerated partial breast irradiation from a single institution" ASCO Breast 2009; Abstract 210.
Breastcancer.org 7 East Lancaster Avenue, 3rd Floor Ardmore, PA 19003
Learn more about our commitment to your privacy
© 2009 Breastcancer.org - All rights reserved.
Breastcancer.org is a non-profit organization dedicated to providing information and community to those touched by this disease. Learn more about our commitment to providing complete, accurate, and private breast cancer information.
