Like surgery, radiation is a localized treatment. The radiation is aimed at a specific area and affects only that area. (Chemotherapy and hormone therapy, in contrast, are systemic treatments and affect your entire body through your bloodstream.)
Radiation is ordinarily used in conjunction with a lumpectomy. Some women who have a mastectomy may also receive radiation. It is used to get rid of any cancer cells that may have been left behind after removing the cancer and breast tissue. Radiation treatments are scheduled and spaced out, once a day for a given number of weeks. There is always a balance between killing as many of the cancer cells as possible and avoiding injury to the normal tissue. The treatment schedule varies from place to place.
Radiation is ordinarily used in conjunction with a lumpectomy
Even though the actual radiation treatment is quite short—minutes—it can be quite difficult for someone to get to the hospital every day for as many as six weeks, especially if she lives in a rural area or doesn’t have transportation. In fact, some women choose a mastectomy over a lumpectomy and radiation solely because the thought of getting to the hospital every day for six week is so daunting.
Seeking to find ways to give effective but less time consuming radiation for women who have had a lumpectomy, researchers developed what is called partial breast radiation. It is given directly to the tumor site over a shorter period of time, sparing the rest of the breast.
Usually, radiation is given in two parts. First, the breast as a whole is radiated from the collarbone to the ribs and the breastbone to the side, making sure the entire area is treated, including, if necessary, lymph nodes. This is the major part of the treatment and lasts about five weeks. Second, you may be given a boost—extra radiation to the tumor’s location.
When you meet with the radiologist, make sure you are offered options. Ask what your risk of local recurrence is with and without radiation therapy. Ask about different techniques like whole breast radiation (WBI), accelerated whole breast radiation (AWBI), accelerated partial breast radiation (APBI), and even intraoperative radiation (IORT). Also ask your radiologist why they are recommending one option versus another.
Each radiation option takes a different approach and it’s important to understand your treatment. Partial breast radiation requires the placement of a balloon into the biopsy cavity at surgery so the treatment can be delivered directly to the tumor bed twice a day for five days. The whole breast option takes six weeks, while the accelerated whole breast approach takes only three weeks. Intraoperative radiation is given while you are on the operating table and so is the quickest, if it is an option for you.
Partial breast radiation
Partial breast radiation is a safe option for women with early breast cancer (less than two cm, negative sentinel node), particularly if postmenopausal. It can be done with classical radiation machines, usually in five visits.
Balloon-delivered intracavitary brachytherapy
This is the most commonly used form of partial breast radiation in the U.S. It takes advantage of the fact that after a tumor is removed there is a cavity left behind in the breast that fills up with fluid as the area slowly heals. Since tumor cells are most likely to be left behind in the lining of that cavity, it makes sense to use the cavity to deliver the radiation. If you have this type of radiation, your surgeon will insert an empty surgical balloon with an attached catheter into the cavity. The treatments themselves consist of hooking the protruding catheter to a computerized delivery device that fills the balloon with the radioactive material. This is done twice a day, six hours apart, for five days. At the end of each treatment the radioactive material is removed and you are unattached from the treatment machine, free to go about your business. You are not radioactive. There are several radiation delivery devices on the market, each with its own benefit. Most commonly used is the Mammosite. If you are interested in using this approach, the key is to find an experienced treatment team and going with the device they are most comfortable with using.
Interstitial brachytherapy
This was previously used to give an extra boost of radiation before the days of the electron beam. Now it has a more primary role. For this procedure, thin plastic tubing is hooked like thread into a needle and drawn through a spot on the breast where the biopsy was done. The tubes are placed while you’re in the operating room or during an outpatient procedure. The number of tubes varies, and sometimes they are inserted in two layers. Small radioactive pellets called iridium seeds, which give off high energy for a very short distance, are put into the tubes, treating the immediate area of the biopsy. This implant is left in for 36 to 48 hours; the time varies depending on how active the seeds are, how big your breast is, and how big the tumor was.
Since the radioactive material stays in the catheters the whole time, this radiation can be picked up by people around you, although not in large doses. Normally that’s no problem, but for some people, such as pregnant women, exposure to even that much radiation could be dangerous. You will be kept in the hospital with a sign on the door that reads “Caution: radioactive.” After about 36 hours, both the radioactive sources and the tubes are removed, a process that requires no anesthesia. After this, you can go home, unless there’s some other reason for you to remain hospitalized. While this approach allows a the radiation dose to be given more precisely where it is needed, it is also the most technically difficult way to do partial breast irradiation and so is used less often.
Conformal or intensity-modulated partial breast irradiation
This approach uses external beam radiation. The treatment lasts four or five days.
Perioperative
This approach to radiation starts in the operating room but continues into the postoperative period. It is also partial breast radiation. This technique depends on the placing of a balloon or catheter into the biopsy cavity in the operating room so it can later be loaded or filled with radioactive material.
Frequently Asked Questions
Many people wonder why women are not tested regularly—before symptoms occur—to determine if their cancer has spread.
It seems to go against reason to not do something to try to find metastases early. But the truth is that there is no evidence that any of the tests—PET scans, CT scans, chest X-rays, or blood tests—make any difference in breast cancer survival. Contrary to what most people believe, finding metastatic disease early on does not make it easier to treat or more treatable. That’s because we don’t have treatments that can stop breast cancer once it has spread to other parts of the body. For this to change, we need to develop treatments that can cure cancer after it has spread, and that’s what many researchers are trying to do.
The American Society of Clinical Oncology recommends that women have regular physical exams and mammograms after their breast cancer treatment is completed, but does not recommend routine X-rays, scans, and blood tests unless symptoms are present. Two randomized controlled studies found that none of the screening tests currently used in asymptomatic women with breast cancer provide a survival benefit over waiting for symptoms to develop. So why do doctors do these tests? They give a variety of reasons ranging from “it makes the woman feel better” to “I do it for other cancers, so it is just habit.” But the bottom line is: If a woman learns her cancer has spread through these tests, it only means she will be living longer with the knowledge that she has metastatic disease, not that she will live longer than she would have if she were not diagnosed until symptoms developed.
So while it may seem like your doctor should be doing more, as long as you are having regular physical exams and mammograms, you are doing everything you need to do.
The published research indicates that PET scans can be beneficial to women and their physicians when they are used to monitor a tumor’s response to treatment after metastatic disease has been found. However, there is no evidence that PET scans are valuable in an asymptomatic woman or that having regular PET scans would help women beat cancer. There are two reasons for this:
- The PET scan can only find metastatic disease that is at least two 2cm in size.
- Finding metastatic disease early, or earlier, does not make it more treatable.
It seems to go against reason to not do something to try to find metastases early. But the truth is that there is no evidence that any of the tests—PET scans, CT scans, chest X-rays, or blood tests—make any difference in breast cancer survival. Two randomized controlled studies found that none of the screening tests currently used in asymptomatic women with breast cancer provide a survival benefit over waiting for symptoms to develop. If a woman learns her cancer has spread through these tests, it only means she will be living longer with the knowledge that she has metastatic disease, not that she will live longer than she would have if she were not diagnosed until symptoms developed.
PET scans are probably best used to establish a baseline when there is known metastatic disease to assess and monitor how a tumor is responding to treatment. I agree with the recommendations put out by the American Society of Clinical Oncology and, like them, would not recommend that you have regular PET scans to look for signs of metastatic disease.
The FDA approved the CA 27.29 blood test in June 1996. It is the first and only blood test that is specific to breast cancer. (The two other blood tests that oncologists may recommend for women with breast cancer, the CA 15-3 and the CEA, are tumor marker tests that are used in breast and other cancers.) The CA 27.29 test measures the level of CA 27.29 antigen, which is found in the blood of breast cancer patients. As breast cancer progresses, the level of CA 27.29 antigen in the blood rises. In theory, by monitoring CA 27.29 test results oncologists can determine if the cancer has spread to other parts of the body, which is called metastasis. [Important point: If breast cancer metastasizes to the liver, it does not mean you have liver cancer. It means you have breast cancer cells in your liver, and the treatment used would be treatment for breast cancer, not treatment for liver cancer.]
Unfortunately, the CA 27.29 test is not as reliable as we initially hoped it would be. In statistical terms, it is neither “specific” nor “sensitive” enough to accurately determine if metastasis has occurred. What does that mean?
If a test for metastasis is highly sensitive, it will be good at finding those women who have metastasis and it will produce very few false negatives (women who are told they have negative results when they really don’t). A test needs to be highly sensitive to rule out disease. In other words, when a test is highly sensitive, if a woman tests negative it means she does not have metastasis.
If a test for metastasis is highly specific, it will be good at finding those women who do not have metastasis and it will produce very few false positives (women who are told they have metastasis when they really don’t). In other words, when a test is highly specific, if a woman tests positive it means that metastasis is indeed present.
Since it is not highly sensitive or specific, the CA 27.29 test can go up for reasons other than metastasis, resulting in false positives, and it may not go up when there is metastasis, resulting in false negatives. The CA 27.29 test has been proven to be helpful in following increases in metastasis in women who have already been found to have metastatic disease, allowing doctors to better adjust treatment regimens.
In addition to having the CA 27.29 test, your oncologist may recommend that you have the CEA and CA 15-3 tumor marker tests done as well. Neither of these tests is highly sensitive nor highly specific either. If you choose to have any of these tests done it should be with the knowledge that there is currently no test or scan that can reliably tell us whether a small number of breast cancer cells have gotten into, and have begun growing in, other parts of the body, and that the information you receive may not be accurate.
Should you have the CA 27.29 test done? The American Society of Clinical Oncology recommends against routine testing of markers after a breast cancer diagnosis. Some oncologists recommend that women have this test every three to six months with the hope that they will find metastasis early. The problem is that there is no evidence that finding metastases by a blood test before a woman has symptoms will improve her survival or quality of life. The treatment of metastatic disease is aimed at reducing symptoms and putting the woman into remission. It is hard to improve symptoms if a woman does not have any. Most women whose breast cancer has metastasized do not show any symptoms until the disease is quite extensive. Symptoms of metastatic disease include bone pain, shortness of breath, lack of appetite and weight loss, and neurological symptoms like pain or weakness or headaches.
There are a series of tests that can help find large amounts of cancer cells in other parts of the body. These are called staging tests (this is not the same as the stages of breast cancer), and include chest X-rays, which can find cancer in the lungs, blood tests that can determine if the cancer has spread to the liver, and bone scans, which can help ascertain if the cancer has spread to the bone. CT scans are also used to detect the spread of cancer to the liver, the lungs, a certain area of bone, or even your brain. Like the blood tests, though, these tests are not good at finding small numbers of cancer cells.
Ultimately, the only way to determine whether having routine CA 27.29 testing is right for you is to think about how you want to handle the aftermath of your breast cancer treatment and whether a test that has limitations will be helpful for you. Some women find reassurance in having the CA 27.29 test done; others find the thought of having the test stressful and choose to not have it done. There is no “right” choice. If you do decide to have the test done, here are a few things you should know:
- A normal CA 27.29 level is usually less than 38 to 40 U/ml (units/milliliter), depending on where the lab test is done.
- Because anything under 40 is considered normal, you shouldn’t worry if it’s 20 one time and then 30 another time.
Just because the test result is higher than 40 it doesn’t mean your cancer has spread. Endometriosis, ovarian cysts, first-trimester pregnancy, benign breast disease, and kidney and liver disease are just some of the noncancerous conditions that can raise your CA 27.29 level.