By Dana Casciotti, Ph.D.
Updated by Anna E. Mazzucco, Ph.D.
Women with early-stage breast cancer can safely choose lumpectomy (also called breast conserving surgery) instead of mastectomy if they also undergo radiation treatment to reduce recurrence. However, traditional radiation therapy is given on an outpatient basis 5 days each week for 6-8 weeks, and that is a difficult schedule for many patients. It can be impossible for those living in rural areas, or who have work or family responsibilities that they can’t leave for such frequent treatments. Several newer types of radiation treatments have been developed so that more women can have the choice of lumpectomy with radiation.
Several of these newer radiation treatments seem to be safe and effective. However, research published in December 2011 shows that accelerated partial-breast brachytherapy may not be as safe or effective as traditional radiation treatment.
Accelerated Partial-Breast Brachytherapy vs. Whole-Breast Irradiation
Accelerated partial-breast brachytherapy appeals to many women because it shortens the course of radiation treatment to 1 week. When the traditional Monday-Friday radiation treatments for 6-8 weeks are the only ones available, some women have little choice but to have a mastectomy, since that does not require radiation.
Accelerated partial-breast brachytherapy consists of the temporary placement of radioactive beads within the breast using a catheter. The radiation is targeted only to the area of the breast surrounding the lumpectomy.
This newer therapy is much more convenient, but is it safe and effective?
Dr. Benjamin Smith and his colleagues at M.D. Anderson Cancer Center examined the records of over 130,000 early breast cancer patients in the national Medicare claims database. All patients were treated with lumpectomy followed by radiation therapy between 2000 and 2007.
Less than 1% of these women used partial-breast brachytherapy in 2000, but that increased to 13% in 2007. When their medical outcomes were compared, women getting partial-breast brachytherapy were significantly more likely to have a mastectomy during a 5-year follow-up period (4% of patients) compared to women who had the regular radiation therapy (2% of patients).
The difference in mastectomy rates could not be explained by age, other health problems, or the presence or absence of cancer in their lymph nodes at the time of initial diagnosis. The researchers concluded that brachytherapy more than doubled the risk of having a mastectomy in the treated breast within 5 years, compared to standard radiation therapy.
Partial-breast brachytherapy was also more likely to cause wound infection, breast pain, tissue injury, and other noninfectious complications like post-operative bleeding. Therefore, the new therapy seems more likely to cause patients additional problems after treatment compared to standard radiation therapy. It is assumed that those complications, or a recurrence of cancer in that breast, are the reasons for the mastectomy within 5 years.
The study is not a clinical trial, and clinical trials are considered a more accurate way to evaluate complication risks. Based on these results so far, standard radiation therapy seems to be safer and more effective than new, partial-breast brachytherapy.
However, we will have more conclusive results when findings are available from a major randomized trial that is part of the National Surgical Breast and Bowel Project. Unfortunately, those results are not expected for a few more years.
Dr. Smith’s study results were published online in The Oncology Report on December 7, 2011.
Other Partial Breast Radiation Treatments May be a Better Choice
Brachytherapy is just one type of partial breast radiation treatment being studied. A research trial called TARGIT-A has had good results treating women with early-stage breast cancer with one dose of partial-breast irradiation given at the time of surgery. This new technology is known as “single-dose targeted intraoperative radiotherapy with Intrabeam.” A study published in 2010 shows that cancer recurrence and side effects after 4 years were similar in women receiving the new, single-dose treatment compared to standard whole-breast radiation therapy.1
There are several other new partial breast radiation treatments which are being studied. One of these is intensity-modulated radiation therapy (IMRT), which guides the radiation beams to the exact location of the cancer. The goal is to reduce exposure to healthy tissue. Another type of partial breast radiation which can also be given in just 5 days instead of the 4-6 weeks used for traditional radiotherapy is 3-Dimension Conformal radiotherapy (3D-CRT). This treatment uses a special mold which guides the radiation to the exact location of the cancer, while avoiding the surrounding healthy area. Longer-term studies are needed to make sure these new radiation therapies are as effective at preventing recurrence and improving survival. Meanwhile, your radiation oncologist can help you decide whether any of these options might be a good choice for you, which may depend on the size, shape, location and type of tumor.2
Alternative Full Breast Radiation Treatment
There is also a newer type of radiation therapy given in fewer but larger doses, called hypofractionated radiation therapy. This therapy, when applied to the full breast over a 3-week treatment period, has been a safe alternative to standard radiation therapy for some women with early-stage breast cancer.3
These positive results, published in 2010, are based on 10 years of follow-up after treatment for women who had undergone breast-conserving surgery for early-stage invasive breast cancer with clear surgical margins and cancer-free axillary lymph nodes.
In addition to the dose and schedule of the radiation, the position of the patient during radiotherapy may also be important. Several studies have shown that having the patient lie on her stomach, (called the “prone” position) rather than on her back, reduced unwanted radiation exposure to the chest and lungs. There is evidence that radiation received to the chest during breast radiotherapy can increase a woman’s chance of heart problems later in life. Women may want to ask their doctor about the advantages of prone breast therapy, especially if the cancer is in the left breast, near the heart.4,5
Doctors and researchers are studying these and other new radiation technology to examine long-term survival and complications. New radiation treatments may prove to be as safe and effective as standard radiation therapy, or perhaps even better, and there have been some promising results so far. However, more research is needed before it is possible to conclude whether these treatments reduce recurrence or save lives in the long-term, compared to no radiation or traditional radiation. Currently, traditional radiation therapy is known to save lives and reduce recurrence for 15 years after treatment,6 and we have to wait for future research results to know if other types of radiation are as safe or effective.
- Vaidya JS, Joseph DJ, Tobias JS, et al. Targeted intraoperative radiotherapy versus whole breast radiotherapy for breast cancer (TARGIT-A trial): an international, prospective, randomised, non-inferiority phase 3 trial. Lancet. 2010 Jul 10;376(9735):91-102. Available at: href=”http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2810%2960837-9/fulltext”>http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2810%2960837-9/fulltext ▲
- Smith et al. Accelerated Partial Breast Irradiation Consensus Statement From the American Society for Radiation Oncology (ASTRO). Int. J. Radiation Oncology Biol. Phys., Vol. 74, No. 4, 2009; pp. 987–1001. ▲
- Whelan TJ, Pignol JP, Levine MN, et al. Long-term results of hypofractionated radiation therapy for breast cancer. N Engl J Med. 2010 Feb 11;362(6):513-20. Available at: href=”http://www.nejm.org/doi/full/10.1056/NEJMoa0906260″>http://www.nejm.org/doi/full/10.1056/NEJMoa0906260 ▲
- Mulliez, et al. Hypofractionated whole breast irradiation for patients with large breasts: a randomized trial comparing prone and supine positions. Radiother Oncol. 2013 Aug;108(2):203-8. ▲
- Henson, et al. Radiation-related mortality from heart disease and lung cancer more than 20 years after radiotherapy for breast cancer. Br J Cancer. 2013 January 15; 108(1): 179–182. ▲
- Wapnir IL, Dignam JJ, Fisher B, et al. Long-Term Outcomes of Invasive Ipsilateral Breast Tumor Recurrences After Lumpectomy in NSABP B-17 and B-24 Randomized Clinical Trials for DCIS. J Natl Cancer Inst 2011;103:478–488. ▲