There are many things we don’t know about breast cancer: researchers haven’t yet pinpointed specific causes, determined why one woman develops the disease and another doesn’t, or discovered how to prevent or cure it. New data even suggests that some breast cancers may disappear on their own, but we don’t really know why. One thing we do know for sure: breast cancer is unpredictable. It may disappear after initial treatment, but there is no guarantee that it won’t return, even after mastectomy.

Knowing your cancer has reappeared can turn your world upside down. You’ve already dealt with the shock of your initial diagnosis, completed treatment, and your life is finally back on track. You’ve done everything you could, eating right, watching your weight and getting plenty of exercise. Why, then, are you facing the breast cancer ordeal all over again?

Why cancer comes back

Treatment for a first diagnosis is designed to eradicate the existing cancer and also lessen the chance of recurrence. Lumpectomy, for example, removes the tumor; follow-up radiation destroys any remaining cells and cuts by half the likelihood that the breast cancer will be found again. Despite our best efforts, recurrence does happen. It is a cancer that returns in or near the same location after treatment. This is different than a new primary cancer, which is a tumor of a different diagnosis and location than the original.

A recurrence doesn’t mean you or your doctor did anything wrong or that your initial treatment was ineffective. Sometimes microscopic cancer cells—even one single cell—survive treatment. Too small to be detected, these rogue cells can remain dormant or continue to multiply, eventually growing until they are large enough to be felt or found on a mammogram. This can happen soon after treatment or years later. About 20% of survivors have recurrences, most within three to five years after their initial treatment. The longer you are cancer-free after the five-year milestone, the less likely you are to face breast cancer again.

All risk is not the same

Anyone who has heard “you have breast cancer” may hear it again; yet the rates and reasons for returning breast cancer vary from woman to woman, depending on a variety of risk factors. The location of your original tumor, its “personality” and how it was treated are significant. A woman who has a lumpectomy to remove a very small, early-stage tumor confined to the breast, for example, is far more likely to have a recurrence than a woman with a similar tumor who has radiation after her surgery. Three of four women with early-stage breast cancer confined to the breast don’t have a recurrence after completing initial treatment.

Between 30-60% of women who have a first breast cancer in the lymph nodes eventually develop it somewhere else in the body. Recent studies suggest this exceptionally high rate may result when random cancer cells are ignored. Most doctors recommend chemotherapy and sometimes hormone therapy for lymph tumors of 2mm or larger, but because current guidelines categorize very small isolated cancer cells as “node negative” and not much of a threat, they’re often not treated. New research, however, shows that even the tiniest spread of breast cancer to the lymph nodes increases the risk of recurrence to 50% in the next five years.

• Your cancer is less likely to reappear if:
• Your breast cancer was small and found early. About 10% of women with stage I tumors (less than 2 cm) that have not spread to the lymph system have a recurrence, while a stage III tumor (up to 5 cm) in the lymph nodes returns about 70% of the time.
• Your lymph nodes were completely clear of cancerous cells.
• Your cancer was not particularly aggressive.
• You had chemotherapy and/or hormone therapy after lumpectomy or mastectomy.
• You are cancer-free for 5 to 10 years after your initial treatment.

Other individual factors also influence whether breast cancer returns. The risk is greater for women who are initially diagnosed before age 40; their tumors are generally more aggressive than those of older women and they live longer, giving the cancer more time to reappear. African American women or those who have estrogen-receptor-negative tumors are also at higher risk for recurrence. And while a family history or genetic predisposition to breast cancer isn’t known to increase the likelihood of recurrence, about 85% of breast cancers in women who have BRCA1 mutations are triple-negative tumors, which are more likely to return.

A simple genomic test can determine whether many women will benefit from chemotherapy, and predict whether they have a low, medium or high risk of recurrence within 10 years. Using tumor samples from a biopsy, lumpectomy or mastectomy, the Oncotype DX test examines the prevalence and activity levels of 21 different genes. Current candidates are women diagnosed with invasive stage I or stage II estrogen-receptor-positive breast cancer with no lymph node involvement. Future versions of the test will likely include other types of breast cancer tumors. Oncotype DX is now included in the National Comprehensive Cancer Network treatment guidelines and is covered by most insurance.

Signs of recurrence

Like an initial diagnosis, catching a returned cancer at its earliest stages is critical. So it is important to remain vigilant once you complete treatment. Continue to carefully examine both breasts each month, and have the clinical exams, follow-up tests and mammograms suggested by your doctor. Notify your doctor immediately of any of the following changes, which may signal a recurrence:

• A lump of any size in or near the breast or in the underarm.
• A lump of any size in or near the breast or in the underarm.
• A change in the way your breast skin looks or feels (red, swollen, scaly, dimpled, puckered or unusually warm).
• A change in your nipple, including redness or a bloody or clear discharge.

These changes don’t necessarily mean your cancer has reappeared. A lump might be scar tissue or fatty tissue from surgery, and red or scaly skin might simply be a rash. But it’s so much better to be safe than sorry, as the saying goes, so it makes sense to let your doctor decide.

The longer you go without a recurrence, the better your prognosis. A non-invasive cancer that returns after five years, for instance, is generally addressed more effectively than an invasive tumor found soon after your original treatment. Depending on the new diagnosis, a recurring cancer may be treated with surgery to remove the tumor and chemotherapy to stop cancer cells from growing. Other therapies may also be used, depending on the nature of the tumor.

It's back. Now what?

So your cancer is back and you’re facing treatment again. The second time around can be a daunting and disruptive personal challenge, but the good news is that breast cancer is more often treated successfully than any other recurring cancer. That’s because doctors now have a robust arsenal of breast cancer weapons.

If you find yourself diagnosed a second time, your healthcare team will consider the location of your tumor, its characteristics, and your previous treatment to determine the most effective approach. The first step is to determine to what degree the breast cancer has returned.

Local recurrence. Two-thirds of breast cancers that return in the same breast come back at the original site or close to it. (A tumor found in a different part of the breast or the opposite breast is usually a new cancer.) Even after mastectomy, breast cancer can reappear in the surgery scar, the chest wall or the breast skin.

Most women with a local recurrence have no signs of the cancer beyond the breast. Mastectomy is usually the preferred treatment, because breast radiation isn’t recommended more than once. Lumpectomy with radiation might be an option for women who haven’t had previous breast radiation, or in some cases, had only partial radiation. If you’ve had breast reconstruction after mastectomy, a local recurrence might surface as a lump near the scar or under the skin; your implant or tissue flap reconstruction may be have to be removed to excise the new tumor.

Regional recurrence. This is rare; only 2% of recurring breast cancers are regional -- meaning the cancer has returned in the lymph nodes. A tumor limited to the underarm nodes is simply removed. Recurrence in the nodes above or below the collarbone may be the sign of more aggressive tumors and requires additional therapies.

Distant recurrence. Known as metastatic disease, this is when cancer has spread beyond the breast, usually to the bones, brain, lungs or liver. Breast cancer in the bones can be treated more effectively than a recurrence anywhere else. Metastasized breast cancer cannot be cured, because even large doses of chemotherapy can’t completely destroy so many cancer cells in the body. Surgery isn’t often an option, because a distant recurrence usually appears in multiple locations. Different treatment regimens are used to control tumor growth and relieve symptoms. If one treatment doesn’t work, another can be tried. Many women experience one or more remissions, even starting and stopping treatment several times.

Understanding chemo

Additional treatments before or after surgery address the personality and tenacity of each breast cancer. Some cancers become resistant to certain types of chemotherapy, so even if you had chemotherapy to treat your initial diagnosis, your doctor may prescribe a different type for a recurrence. While chemo is probably the one treatment many women fear the most, it is the most commonly used, because it is widely effective.

Hormonal therapies are effective for the 60% of breast cancers that need estrogen or progesterone to grow. These hormone-receptor-positive tumors respond better to therapies that reduce hormone levels in the body. These medications, which are not the same as hormone replacement therapy prescribed for menopausal symptoms, lessen the odds of the cancer returning and work for both premenopausal and postmenopausal women. Hormone-receptor-positive tumors can be treated more effectively than hormone-receptor-negative cancers, because several therapies are now available and new medications are being developed. Some work better than others. Tamoxifen reduces the risk of hormone-receptor-positive breast cancer returning in premenopausal women, while Arimidex, Aromasin and Femara are now standard-of-care for postmenopausal women with the same kind of tumors.

Targeted therapies are medications engineered to block or attack specific molecular structures of cancer cells. Herceptin and Tykerb are targeted therapies that benefit women with HER2-positive tumors—HER2 is a protein in normal breast cells; when cancer cells have too much HER2, they grow quickly. Herceptin treats advanced breast cancer by attaching itself to HER2-positive cells and blocking tumor growth. When Herceptin isn’t effective, Tykerb, a newer targeted therapy, is used. Women with advanced HER2-negative tumors who haven’t had chemotherapy may be treated with Avastin. Used in combination with chemo, Avastin destroys HER2-negative tumors by blocking the growth of new blood vessels the cells need to survive.

Return to hope

We still have no cure for breast cancer, and anyone who develops the disease once may be diagnosed again. But our arsenal of surveillance, diagnosis and treatment tools are now more individualized, more varied, and more effective. If your cancer returns, you will be treated with methods that are better than what was available just a few years ago.

Facing cancer again can be just as scary as the first time around. Remember that you do not have to face the challenge of recurrence alone. Consult with a doctor you trust and get a second opinion regarding pathology and treatment. Take the time to understand your diagnosis, the benefits and risks of treatment alternatives, and be involved in decisions. Surround yourself with supportive individuals and let others help you. Join a support group. Speak to an advocate who can help you sort through your feelings and the decisions you need to make. Take care of yourself, rest when you need it. Embrace life and go on living.

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Kathy Steligo is a freelance business and health writer who has more than a nodding acquaintance with breast cancer. Diagnosed twice, she has had five biopsies, two lumpectomies, radiation, sentinel node biopsy, genetic counseling, genetic testing, bilateral mastectomies, implant reconstruction, and a second GAP reconstruction. Kathy is the author of The Breast Reconstruction Guidebook, and writes for numerous publications, websites, physicians and health organizations.