By Pamela Benitez, MD
Dr. Benitez currently practices at Beaumont Cancer Center of William Beaumont Hospital in Royal Oak, Michigan. As a General Surgeon, she presently specializes in the treatment of Diseases of the Breast and Breast Cancer. Board certified by the American Board of Surgery, she has been in practice for 23 years. Dr. Benitez is affiliated with Beaumont Hospitals and has been on staff at William Beaumont Hospital - Royal Oak for 18 years and at William Beaumont Hospital - Troy for 16 years. Dr. Benitez attended Washington University in St. Louis, Missouri for her undergraduate years, received her medical degree from Albany Medical College, and did her residency at the University of Michigan in General Surgery
Partial Breast Irradiation: The Latest in Breast Cancer Treatment
Today, 63 percent of breast cancer patients are diagnosed when the disease is still in a localized stage. Thanks to earlier detection and improved treatments, women now have options other than undergoing a mastectomy to treat their cancer, and the prospect for sustained recovery from breast cancer is better than ever. A growing number of patients are opting for a less invasive course of treatment consisting of tumor excision via lumpectomy followed by radiation therapy to the breast to reduce the likelihood of recurrence. Dr. Pamela Benitez of Beaumont Cancer Center has answered some commonly-asked questions about lumpectomy and the radiation treatment for Dr.Donnica.com.
What is the difference between radiation treatment and chemotherapy?
Radiation therapy is treatment delivered to a specific area of the body using high-energy rays or particles that destroy cancer cells. This treatment may be used to destroy cancer cells that remain in the breast, chest wall, or underarm area after surgery. Surgery and radiation therapy are examples of local therapies for breast cancer that are intended to treat a tumor at the specific site and does not treat the rest of the body. Chemotherapy is a systemic therapy (treating the whole body) that is delivered by medicine taken by mouth or given directly into the bloodstream to reach cancer cells that may have spread beyond the breast. The key difference is that radiation treats a specific, local site and chemotherapy treats the whole body. The whole body cannot receive radiation therapy.
How long does radiation treatment take?
Historically, women undergoing radiation therapy for breast cancer have received external beam, whole breast radiation therapy. The radiation is delivered from a source outside the body and focuses on the area affected by the cancer. This usually includes the whole breast and, depending on the size and extent of the cancer, may include the underarm area as well. External beam therapy takes six to seven weeks with a treatment every day, five days a week. This treatment plan can impose time and travel burdens on some patients-particularly those who are working, have family commitments, are elderly, and/or live far from a radiation facility. Recently, the medical community has seen a trend toward another therapy called partial breast irradiation, a method for delivering radiation therapy to the lumpectomy area only of breast cancer patients. This treatment, partial breast irradiation, can be completed in 5 days.
What is partial breast irradiation?
Partial breast irradiation refers to the delivery of radiation to the area directly surrounding the original tumor (the lumpectomy bed), the site where recurrence of breast cancer in the breast is most likely to occur. This allows women to receive a shorter course of treatment (typically five days) and also minimizes radiation exposure to the rest of the breast, skin, ribs, lungs and heart. The treatments are twice a day for five days. Partial breast irradiation helps women get through their treatment and back to their normal lives faster.
Why was partial breast irradiation developed?
Partial breast irradiation was developed for several reasons. In order to reduce the local recurrence of breast cancer after breast-conserving surgery, radiation treatment is necessary. Some patients decline to have or omit the radiation therapy and thus incur an increased recurrence of their cancer. This is considered inadequate treatment. The reasons that women cite for not having radiation therapy are the time commitment for whole breast radiation (six to seven weeks), the distance to a radiation therapy facility, the fear of a long course of radiation, the possible side effects of whole breast radiation, and the possible loss of income from the time commitment for whole breast radiation. The second major concern is the number of women who chose to have a mastectomy (remove her breast completely) to avoid having radiation therapy even though they could preserve their breasts. These women cite the same reasons as noted above but also include the women who did not want to trouble others to help with transportation to and from the radiation facility for the long course of therapy. And there are women who are not offered the option of breast preservation at all even though they may be candidates for breast conserving therapy. Eliminating the time and travel burdens associated with external beam radiation therapy may allow more women to preserve their breasts with breast conservation therapy.
In addition, it has been noted that the percentage of women who develop a new cancer in the breast treated with whole breast radiation therapy, at a site a distance away from the original tumor site, is the same as in women who did not have whole breast radiation therapy at all.
How is partial breast irradiation delivered?
There are a number of ways in which partial breast irradiation can be delivered, the most common being with the MammoSite® balloon catheter. The MammoSite balloon catheter is placed in the breast into the lumpectomy bed after the tumor has been removed. From this internal location in the breast, the radiation therapy is delivered to the targeted breast tissue in what is typically a five-day course of treatments. This is the site where most local recurrences will occur and thus, the radiation is delivered directly to the tissue at risk. This therapy has been used to treat thousands of patients worldwide. During the lumpectomy procedure or shortly thereafter, the MammoSite balloon is placed inside the lumpectomy cavity. The patient returns to the hospital or clinic for treatment on an outpatient basis where a radioactive "seed" is inserted into the balloon. The actual treatment takes only five to fifteen minutes and is delivered twice a day for five days. The balloon stays in place for the entire treatment time and is well-tolerated by the patients who have had this therapy. Most women report that having the catheter in the breast is not painful. No source of radiation remains in the patient's body between treatments or after the final procedure. The balloon is deflated after the final treatment and easily removed.
When partial breast irradiation was first studied, the delivery of partial breast irradiation was accomplished utilizing many small hollow tubes inserted into the breast tissue that traversed the lumpectomy cavity. This is called interstitial catheter radiation therapy. Multiple "seeds" were placed in each of these tubes. The method was quite cumbersome. From that technology the MammoSite balloon catheter was developed. The MammoSite balloon catheter is much more comfortable for the patient than were the multiple hollow tubes. The delivery of the radiation therapy is also easier for physicians to prescribe using the MammoSite balloon.
Other methods for delivering partial breast irradiation are being developed but have not undergone appropriate testing. Some of these other methods deliver more radiation to other areas of the breast and chest wall, as with whole breast radiation, rather than the targeted, focal treatment offered by the MammoSite balloon catheter.
Is partial breast irradiation as effective as whole breast radiation?
A five-year follow-up study published in the Journal of the National Cancer Institute found that partial breast irradiation using interstitial catheter radiation therapy produces comparable results to whole-breast radiation therapy in preventing breast cancer recurrence in appropriately selected women treated with breast-conserving therapy. Based on rapidly growing clinical evidence on the effectiveness of partial breast irradiation, the American Society of Breast Surgeons has published selection criteria for patients for whom partial breast irradiation (PBI) would be considered an appropriate treatment in lieu of external beam whole breast radiation.
At Beaumont Cancer Center, we are continually striving to provide advanced treatment options to women with breast cancer to lessen the burden of their treatments during what is understandably a very stressful time. Our center was involved with the development of partial breast irradiation and in the clinical trials of MammoSite balloon catheter radiation therapy. We continue to offer partial breast irradiation with breast-conserving surgery. Partial breast irradiation provides a sensible, clinically proven alternative to six weeks of whole breast radiation therapy. Radiation therapy delivered with the MammoSite balloon is a minimally invasive means of providing partial breast irradiation for patients that, coupled with the short treatment time, could make it easier for more women to preserve their breasts with a lumpectomy followed by radiation therapy and receive the appropriate treatment of her breast cancer.
For up-to-date information regarding geographic availability of MammoSite, go to www.mammosite.com .
Created: 4/22/2007  - Donnica Moore, M.D.