Breast brachytherapy is the method for treating breast cancer available at the University of Wisconsin. Since no two cancer patients are the same, the procedure is personalized for each patient using staff from the UW Hospital, UW Department of Human Oncology, UW Comprehensive Cancer Center and the UW Medical School.
Without further treatment, 30 to 40 percent of women will have the cancer return in the original location. The addition of radiotherapy after the lumpectomy reduces the risk to approximately 10 percent. Breast brachytherapy uses a higher dose of radiotherapy than traditional radiation therapy so the treatment can be administered over the course of one week, instead of six to seven weeks with traditional radiation therapy, making breast brachytherapy ideal for busy working women, elderly patients and those who live far from a radiation treatment center.
This Web site provides more information for those interested in being treated with breast brachytherapy at the University of Wisconsin, including background information about the procedure and information about who is eligible. Please contact a member of our staff if you would like to set up a consultation.
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Background
Several large studies have shown equivalent outcomes between mastectomy (removal of the entire breast) and breast conservation therapy in women with early stage breast cancer. After the surgeon removes the cancer lump (lumpectomy), 30-40 percent of women will have the cancer return in the original location without any further treatment. The addition of radiation therapy reduces this risk to around 10 percent. This involves 6-7 weeks of daily radiation therapy to the entire breast with x-rays (similar to a chest x-ray but more focused and higher energy). This often proves to be difficult for busy working women, elderly patients and those that live far from a radiation treatment center.
The advent of high-dose rate (HDR) partial breast brachytherapy allows temporary placement of small radioactive seeds within the breast surrounding the lumpectomy in the area at highest risk of having a cancer left behind. This literally delivers precise radiation from the inside out in the region at greatest risk of recurrence. This more focused, tailored therapy allows us to safely increase the daily dose and significantly shorten the radiation treatment time from 30-35 visits over 6-7 weeks down to 8-10 visits over one week and avoids radiation to the normal uninvolved nearby structures including the skin, heart, lung, and opposite breast. This offers a more convenient option for women following surgery with less side effects.
Brachytherapy is also used as standard treatment for many other cancers including prostate cancer, and gynecologic cancers (cervix, vagina, uterus) as well as several other less common cancer sites.
Procedure
The first step is a consultation in our Radiation Oncology department where you will meet several members of our experienced breast cancer team including nurses and physicians. We will arrange for your medical records to be sent to us in advance such that we can review the details of your medical history, x-rays (mammograms, ultraounds, etc), surgery reports, and other relevant information. During your visit, we will fully discuss available treatment options with you including outcomes, potential side effects, role of chemotherapy and hormonal therapy and follow-up care.
There are several distinct procedure methods that can be used: supine ultrasound-guided, supine CT-guided, and prone digital mammo-guided. Based on the details of the surgery, location of the initial cancer and individual anatomy, a unique, specific approach will be planned for you. All of the procedures involve placement of thin flexible plastic catheters (hollow tubes with the thickness of pencil lead) in the breast surrounding the lumpectomy cavity. The procedure is done as an outpatient while you are awake and takes 60-90 minutes. Local anesthetic is used liberally to make the procedure relatively pain-free. You will be given a special support surgi-bra that wraps around the catheters for maximal comfort and discreteness during your week of treatment.
After you leave the department, there is no radiation inside your breast, and you are free to go about your activities. A CT scan is obtained for treatment planning after which the treatments are delivered over 4-5 days. Each visit usually takes between about 15-20 minutes during which time the catheters are hooked up to the brachytherapy unit. Usually 2 treatments are given daily at least six hours apart. You can be with your family members and friends between treatments with no risk to them since you are not radioactive. After treatment on the last day, the catheters are easily removed with very little discomfort. For patients traveling from out of the area, local housing arrangements with free shuttle service can be made at discounted rates for the one week of treatment.
We will arrange a followup evaluation 4-6 weeks after treatment for you. For those patients traveling from out of the area, a tailored followup schedule involving your local physicians will be coordinated. Typically, mammograms are obtained at 6 months after radiation and yearly thereafter.
Patient Selection
Selection criteria for partial breast brachytherapy include patients with early-stage breast cancer with a very low risk for disease beyond the lumpectomy region (outside the area treated by partial breast radiation) based on prognostic factors. These include patients with small tumor size, uninvolved or negative margins (no cancer at the edge of what was removed) and limited nodal involvement.
- Invasive ductal, medullary, papillary, colloid (mucinous), tubular histologies or Ductal carcinoma in situ (DCIS)
- Tumor Stage: Tis, T1, T2 if lesion = 3 cm
- Nodal Stage: N0 (negative sentinel node mapping is acceptable) or N1(1-3 nodes positive and no extracapsular extension). This represents a cohort of patients that would not ordinarily receive axillary irradiation.
- Clearly visible target as defined by ultrasound, surgical clips, or mammography
- Unifocal breast cancer (single focus which can be encompassed by one lumpectomy)
- Negative surgical margins
- Negative post-lumpectomy mammogram if cancer presented with malignancy-associated microcalcifications
- No Paget's disease of the nipple or extensive intraductal component (EIC)
- No previous radiation or chemotherapy for current breast cancer
- No collagen vascular disease (systemic lupus erythematosis, scleroderma, or dermatomyositis)
- Over age 18 years old
- No pregnant or lactating women.
Side Effects
Breast brachytherapy is more localized than standard external beam radiotherapy, so there is less dose to the rest of the breast, skin, ribs, muscle, lung, and heart. By its nature, however, brachytherapy results in an uneven dose, which is more intense or greater in the center close to the catheters near dwell positions of the Iridium-192 radioactive source. This radiation, in dose, may be beneficial if all of the tumor is in the high dose region, or it could lead to side effects if the normal breast or skin tissues are damaged.
Scar tissue is always a possible consequence of radiation therapy. Scar tissue may appear as firm or thickened region of the breast in the high dose zone of brachytherapy, or as permanent pockmarks where the catheters enter or exit the skin. Modern technology, however, minimizes this risk through computerized dosimetry which detects and reduces excessive high doses in the treatment volume, and by preventing the radiation source from dwelling at the skin surface.
If fat cells near a catheter becomes damaged by the radiation, fatty acids can enter breast tissue and cause irritation. This inflames that part of the breast and results in a red, swollen, and tender area which mimics infection. Unlike infection which occurs within weeks of the implant, fat necrosis appears 4-12 months later. In the initial experience with breast brachytherapy, before we had learned computerized methods to even out the dose distribution, the chance of symptomatic fat necrosis was approximately 10%. Now it is below 2%. Treatment of this problem usually starts with nonsteroidal anti-inflammatory medications (i.e, motrin). If that intervention doesn't help, a course of steroids may be indicated. Drainage or surgical removal of the damaged tissue should only be required as a last resort and rarely is necessary.
Anytime a catheter is inside the body, there is a small possibility for infection. We will monitor you for signs of infection during your treatment and may prescribe antibiotics if necessary. Antibiotics have been prescribed for less than 10% of our patients.
Most cases of catheter insertion result in minimal bleeding, because the catheters themselves compress blood vessels and the epinephrine within the local anesthetic mixture causes the blood vessels to constrict. Bruising is occasionally seen, which fades over time. Patients, taking daily aspirin or other blood thinners, such as Coumadin, should tell their doctor prior to breast brachytherapy.
Alternatives
One alternative to breast brachytherapy is external beam radiotherapy. In this procedure, X-ray machines called "linear accelerators" deliver radiation from outside the body and usually treat through-and-through. Modern linear accelerators were brought into the clinic in the 1960's, and represent the most common method of delivering radiation therapy today. External beam raiotherapy is prefered when a homogenous dose to the entire breast and/or lymph nodes is indicated. In contrast, brachtherapy delivers a localized dose that is greatest where the cancer started and is least in the surrounding healthy tissues.
External beam radiotherapy involves a daily treatment for a duration of six to seven weeks, which may be difficult for the elderly and those who live far from a treatment center. Breast brachytherapy consists of one or two treatments daily for four to five days, and may benefit women who live far from a facility or who are too busy to undergo daily treatments for several weeks or more.
More Information
Breast cancer is a disease that affects one in eight women in the United States. Men are also at risk for breast cancer, though occurances are rare. Eight out of 10 breast cancers are found in women over age 50, but it can affect women and men of all age groups. Knowing preventative health measures and getting routine exams are just a few of the ways to reduce your risk.
The survival rate for breast cancers found early is 96 percent after five years, making regular screening, including yearly mammograms after age 40, an important part of breast health. There are many misconceptions about what causes breast cancer, so knowing the facts and myths about this disease can help you or a loved one cope after a diagnosis.