Breast Cancer: Better Treatments Save More Lives
by Carol Lewis
Two different women. The same deadly disease. One thought she couldn't get it. The other was told she didn't have it. Both opinions were wrong.
In 1994, one week before turning 35, Cathy Young received the devastating news. "I thought people had to be in their 50s to get cancer," the Oak Grove, Mo., resident says. "And then it happened to me."
Linda Hunter, 42, recalls that in January 1995, her mammogram results came back normal. But skin changes on one of her breasts compelled her to seek a second, third and fourth opinion--all of which supported the initial mammogram findings. Her tenacity finally paid off when a fifth doctor she visited detected a rare form of the disease.
Every three minutes a woman in the United States learns she has breast cancer. It is the most common cancer among women, next to skin cancers, and is second only to lung cancer in cancer deaths in women. Only 5 to 10 percent of breast cancers occur in women with a clearly defined genetic predisposition for the disease. The overall risk for developing breast cancer increases as a woman gets older.
Although treatment is initially successful for many women, the American Cancer Society (ACS) says that breast cancer will return in about 50 percent of these cases.
"It's hard to say that things are back to normal when one survives breast cancer," says Young, "because a survivor always has a fear that one day the cancer may return."
New drugs, new treatment regimens, and better diagnostic techniques have improved the outlook for many, and are responsible, according to ACS, for breast cancer death rates going down.
"Women have greater options in breast cancer treatment compared to a decade ago," says Harman Eyre, M.D., chief medical officer for ACS. "New drugs and procedures open up a whole new era of effective treatment."
Breast Cancer Treatments
Breast cancer can be treated with surgery, radiation and drugs (chemotherapy and hormonal therapy). Doctors may use one of these or a combination, depending on factors such as the type and location of the cancer, whether the disease has spread, and the patient's overall health.
Most women with breast cancer will have some type of surgery, depending on the stage of the breast cancer. The least invasive, lumpectomy (breast-conserving surgery), removes only the cancerous tissue and a surrounding margin of normal tissue. Removal of the entire breast is a mastectomy. A modified radical mastectomy includes the entire breast and some of the underarm lymph nodes. The very disfiguring radical mastectomy, in which the breast, lymph nodes, and chest wall muscles under the breast are removed, is rarely performed today because doctors believe that a modified radical mastectomy is just as effective.
While removing underarm lymph nodes after surgery is important in order to determine if the cancer has spread, this procedure may add chronic arm swelling and restricted shoulder motion to the discomforts of the overall treatment. But a new method, sentinel node biopsy, still under investigation, allows physicians to pinpoint the first lymph node into which a tumor drains (the sentinel node), and remove only the nodes most likely to contain cancer cells.
To locate the sentinel node, the physician injects a radioactive tracer in the area around the tumor before the mastectomy. The tracer travels the same path to the lymph nodes that cancer cells would take, making it possible for the surgeon to determine the one or two nodes most likely to test positive. The surgeon will then remove the nodes most likely to be cancerous.
Radiation therapy is treatment with high-energy rays or particles given to destroy cancer. In almost all cases, lumpectomy is followed by six to seven weeks of radiation, an integral part of breast-conserving treatment. Although radiation therapy damages both normal cells and cancerous cells, most of the normal cells are able to repair themselves and function properly.
Radiation therapy can cause side effects such as swelling and heaviness in the breast, sunburn-like skin changes in the treated area, and lymphedema (swelling of the arm due to fluid buildup) if the underarm lymph nodes were treated after a node dissection.
Drug Options Expand
Drugs are used to reach cancer cells that may have spread beyond the breast--in many cases even if no cancer is detected in the lymph nodes after surgery.
While doctors once believed that the spread of breast cancer could be controlled with extensive surgery, they now believe that cancer cells may break away from the primary tumor and spread through the bloodstream, even in the earliest stages of the disease. These cells cannot be felt by examination or seen on x-rays or other imaging methods, and they cause no symptoms. But they can establish new tumors in other organs or the bones. The goal of drug treatment, even if there's no detectable cancer after surgery, is to kill these hidden cells. This treatment, known as adjuvant therapy, is not needed by every patient. Doctors will make recommendations regarding specific types of therapy based on the stage of the breast cancer.
FDA has approved several new drugs and new uses for older drugs in recent years that improve the chances of successfully treating breast cancer. These drugs include:
Herceptin: About 30 percent of women with breast cancer have an excess of a protein called HER2, which makes tumors grow quickly. A genetically engineered drug, Herceptin (trastuzumab), binds to HER2 and kills the excess cancer cells, theoretically leaving healthy cells alone.
Herceptin, made by Genentech Inc., San Francisco, Calif., and approved by FDA in September 1998, is an intravenous treatment that is used alone in patients who have had little success with other drugs, or as a first-line treatment in combination with the drug Taxol (paclitaxel).
Recent follow-up research shows that Herceptin, in combination with chemotherapy, also may modestly extend the lives of terminal breast cancer patients. Updated survival figures reported from a two-year study by one of the drug's key developers from the University of California at Los Angeles showed an improvement in survival (about 4 months on average) in those getting Herceptin. Scientists say that while the improvement is small-about four months on average-it is especially noteworthy in a disease that until now has eluded many efforts to slow its progression to death.
Selection of patients who are most likely to benefit from Herceptin is important because of the possible serious risks from the drug, including weakening of the heart muscle that can lead to congestive heart failure. It is not known whether Herceptin has beneficial effects in women with normal levels of the HER2 protein.
FDA also approved in September 1998 a test called DAKO HercepTest to measure HER2 protein in tumors.
Nolvadex: A drug that has been used as a breast cancer treatment for more than 20 years, Nolvadex (tamoxifen citrate) was approved by FDA in October 1998 for breast cancer risk reduction in high-risk women.
Doctors know that estrogen promotes the growth of breast cancer cells. Tamoxifen interferes with the activity of estrogen by slowing or stopping the growth of cancer cells already present in the body. As adjuvant therapy, tamoxifen has been shown to help prevent both the original breast cancer from returning, and also the development of new cancers in the other breast.
A National Cancer Institute study showed that the drug reduced the short-term chance of getting breast cancer by 44 percent in women who were judged to be at increased risk for the disease. FDA emphasizes, however, that tamoxifen, manufactured by Zeneca Pharmaceutical Inc., Wilmington, Del., will not eliminate breast cancer risk completely, and should be used only following a medical evaluation of individual risk factors.
Due to potentially serious side effects, including endometrial (lining of the uterus) cancer and blood clots in major veins and the lungs, the American Society of Clinical Oncology recommends that patients talk with their regular health-care providers to determine whether individual medical circumstances and histories are appropriate for considering use of tamoxifen.
Xeloda: Xeloda (capecitabine), made by Hoffmann-La Roche, Nutley, N.J., was approved by FDA in April 1998 for the treatment of breast cancer that has spread to other parts of the body (metastasized) and is resistant to both paclitaxel and an anthracycline-containing regimen. Xeloda does not kill the cancer cells directly. Instead, once the drug enters the cancer cells, it is metabolized to 5-fluorouracil (5-FU), a drug routinely used for breast cancer. The advantage of Xeloda, in addition to the convenience of its pill form, is that cancer cells actively convert it to 5-FU, but normal cells convert very little to 5-FU.
Taxotere: In May 1996, FDA gave accelerated approval to Taxotere (docetaxel) to treat patients whose locally advanced or metastasized breast cancer has progressed despite treatment with other drugs. The approval was conditional on the manufacturer, Rhone-Poulenc Rorer Pharmaceuticals, Inc., Collegeville, Pa., conducting additional studies. In June 1998, after additional studies confirmed its safety and effectiveness, the drug was granted full FDA approval.
In addition to these newer drugs, combinations of the anticancer drugs Cytoxan (cyclophosphamide) and Adriamycin (doxorubicin), with or without Adrucil (fluorouracil), may be used to treat breast cancer.
Chemotherapy (drug treatment) is given in cycles, with each period of treatment followed by a recovery period. The total course of chemotherapy can last three to six months, depending on the drugs and how far the cancer has spread.
Kelly Munsell of Tucson, Ariz., took the combination Adriamycin and Cytoxan in six cycles, spaced three weeks apart, after doctors diagnosed her breast cancer in 1996 at age 27.
"Chemo for me was torture," Munsell recalls, describing profuse vomiting and severe weight gain as two of the serious side effects. But despite the discomfort, Munsell, whose mother and grandmother both died of breast cancer, is glad she underwent the grueling treatment two years ago. "My recent battery of tests came back negative for cancer," she says.
In addition to the drugs actually battling the disease, there also is help for patients in severe pain from cancer. FDA approved Actiq (oral transmucosal fentanyl citrate) in November 1998 as a treatment specifically for cancer patients with severe pain that breaks through their regular narcotic therapy. A narcotic more potent than morphine, Actiq is in the form of a flavored sugar lozenge that dissolves slowly in the mouth. Actiq is approved for patients already taking at least 60 milligrams of morphine per day for their underlying persistent cancer pain.
It is important for every woman to consider herself at risk for breast cancer, ACS says, simply because she's female. At the same time, however, studies continue to uncover lifestyle factors and habits that can alter that risk, and many new chemotherapy drugs and drug combinations continue to be developed and tested in clinical trials. Drugs and procedures currently under investigation include bisphosphonates (a group of drugs routinely used to treat osteoporosis), monoclonal antibodies (similar to Herceptin), and angiogenesis inhibitors (drugs that block the development of blood vessels that nourish cancer cells).
"While death rates from breast cancer are falling, and while there are a number of exciting new strategies being developed," says Michael A. Friedman, M.D., former FDA deputy commissioner and cancer research specialist, "we recognize that a great deal more needs to be done."
Mammography: A Lifesaving Step
The American Cancer Society says that the best strategy for successfully beating breast cancer is to follow guidelines for early detection. Currently, the most effective technique for early detection is screening mammography, an x-ray procedure that can detect small tumors and breast abnormalities up to two years before they can be felt and when they are most treatable. (See "FDA Sets Higher Standards for Mammography" in the January-February 1999 FDA Consumer.)
Studies show that regular screening mammograms can help decrease the chance of dying from breast cancer. Finding a breast tumor early may mean that a woman can choose breast-saving surgery. Furthermore, she may not have to undergo chemotherapy.
Stages of Breast Cancer
Stages of breast cancer, according to the American Cancer Society, indicate the size of a tumor and how far the cancer has spread within the breast, to nearby tissues, and to other organs. Specific treatment is most often determined by the following stages of the disease:
Carcinoma in situ: Cancer is confined to the lobules (milk-producing glands) or ducts (passages connecting milk-producing glands to the nipple) and has not invaded nearby breast tissue.
Stage I: Tumor is smaller than or equal to 2 centimeters in diameter and underarm (axillary) lymph nodes test negative for cancer.
Stage II: Tumor is between 2 and 5 centimeters in diameter with or without positive lymph nodes, or tumor is greater than 5 centimeters without positive lymph nodes.
Stage III: This stage is divided into substages known as IIIA and IIIB:
- IIIA: Tumor is larger than 5 centimeters with positive movable lymph nodes, or tumor is any size with lymph nodes that adhere to one another or surrounding tissue.
- IIIB: Tumor of any size has spread to the skin, chest wall, or internal mammary lymph nodes (located beneath the breast and inside the chest).
Stage IV: Tumor, regardless of size, has metastasized (spread) to distant sites such as bones, lungs, or lymph nodes not near the breast.
Recurrent breast cancer: The disease has returned in spite of initial treatment.
Carol Lewis is a staff writer for FDA Consumer.