Stage 0: The 2 types of stage 0 breast cancer, ductal carcinoma in situ (DCIS) and lobular carcinoma in situ (LCIS), are treated quite differently.

No immediate or active treatment is recommended for most women with LCIS because this condition is not a true cancer. But because having LCIS increases your risk of developing invasive cancer later on, close follow-up is essential. This usually includes a yearly mammogram and a clinical breast exam twice a year. Close follow-up of both breasts is important because women with LCIS in one breast have an equal risk of developing breast cancer on the same or opposite side.

These women may wish to consider taking tamoxifen or participating in a clinical trial for breast cancer prevention (with tamoxifen or raloxifene, for example). They may also wish to discuss other possible prevention strategies (such as changes in diet, an exercise program, or preventive surgery) with their doctor.

Some medical centers have clinical trials to test the value of magnetic resonance imaging (MRI) for patients with LCIS. Some women with LCIS may choose to have a bilateral simple mastectomy (removal of both breasts but not axillary lymph nodes), especially if they have other risk factors such as strong family history, in an attempt to prevent invasive cancer from developing. Depending on the woman's preference, she may consider immediate or delayed breast reconstruction.

Treatment of DCIS depends on mammogram and biopsy results. In most cases, a woman can choose between breast-conserving therapy (lumpectomy, usually followed by radiation therapy) and simple mastectomy. Lymph node removal (axillary dissection) is usually not necessary. Lumpectomy without radiation therapy is usually considered an option only for women with small areas of low-grade DCIS. Mastectomy may be necessary if the area of DCIS is very large, if the breast has several areas of DCIS, or if lumpectomy cannot completely remove the DCIS (that is, the lumpectomy specimen and re-excision specimens have positive margins).

After a lumpectomy, a mammogram should be done to ensure that the disease has been removed. Another way is to x-ray the surgical specimen to make sure it contains all the abnormalities, such as calcifications seen on the original mammogram.

Women having mastectomy for DCIS may have immediate or delayed reconstruction. Recent research suggests that 5 years of treatment with tamoxifen can lower the risk of invasive cancer developing after treatment of DCIS with lumpectomy and radiation therapy.

Stage I: This can be treated with either breast conservation therapy with lumpectomy (removal of the cancer and a narrow margin of surrounding normal breast tissue) or mastectomy and dissection of the lymph nodes under the arm. Radiation therapy should be given after lumpectomy. Breast reconstruction can be done after a mastectomy, either at the time of surgery or later.

Sentinel lymph node sampling may be used instead of standard axillary lymph node dissection. If the tumor is less than 1 cm (nearly 1/2 inch) in diameter, adjuvant systemic therapy is not usually required. Some doctors suggest adjuvant therapy if a cancer smaller than 1 cm has any features that indicate an unfavorable prognosis (microscopic study shows high grade, flow cytometry shows high S-phase fraction, Ki-67 index is high, or estrogen-receptor assay is negative). If the tumor is larger, depending on the features mentioned above, adjuvant chemotherapy or hormone therapy, or both, may be recommended.

Stage II: Surgery and radiation therapy options for stage I and stage II tumors are similar, except that in stage II, radiation therapy may be considered even after mastectomy if the tumor is large (over 5 cm) or has spread to many lymph nodes (4 or more). Adjuvant systemic therapy is usually recommended. Adjuvant therapy may involve hormone therapy, chemotherapy, or both, depending on the patient's age and estrogen-receptor assay results.

An option for some women who would like to have breast-conserving therapy for tumors larger than 2 cm (4/5 inch -- T2 or T3) is to have neoadjuvant (before surgery) chemotherapy to shrink the tumor. The size of these tumors relative to some women's breasts may make lumpectomy difficult or impossible.

If the neoadjuvant chemotherapy shrinks their tumors enough, women may then be able to have lumpectomy, which is followed by additional chemotherapy, radiation therapy, and hormone therapy if the hormone receptor is positive. If the tumor does not shrink enough to permit lumpectomy, then mastectomy followed by different chemotherapy, radiation therapy, and hormone therapy is the usual treatment.

Adjuvant Therapy for Stage I - III Breast Cancer: Adjuvant drug therapy may be recommended, based on the tumor's size, spread to lymph nodes, and/or prognostic features. If it is, you may receive chemotherapy and/or hormone therapy.

Hormone therapy is not likely to be effective for women with hormone receptor-negative tumors. These women usually receive chemotherapy only as adjuvant therapy.

Women older than 50 years who are no longer having menstrual periods and have hormone receptor-positive tumors often receive hormone therapy with tamoxifen as adjuvant therapy. A new alternative is treatment with an aromatase inhibitor. Chemotherapy may also be recommended. This is particularly important if their cancer has spread to lymph nodes.

Women younger than 50 who are still having menstrual periods will usually receive adjuvant chemotherapy. Tamoxifen will also be recommended if the cancer was hormone receptor positive. Other alternatives are surgical removal of the ovaries or chemical suppression of ovarian hormone production.

The typical chemotherapy regimens are most often a combination of cyclophosphamide with doxorubicin or epirubicin with or without fluorouracil. These are usually given for 4 to 6 months. Another regimen is cyclophosphamide, fluorouracil, and methotrexate. Recently, doctors have been using paclitaxel in addition to doxorubicin and cyclophosphamide.

Most doctors recommend that hormone therapy be started after the chemotherapy is completed.

For help in deciding if adjuvant therapy is right for you, you might want to visit the Mayo Clinic Web site at: http://mayoclinic.com/takecharge/healthdecisionguides/avt/pg21.cfm.

Stage III: Smaller stage IIIA breast cancers may be removed by lumpectomy. Modified radical mastectomy (with or without reconstruction) is another option. Surgery is usually followed by adjuvant systemic therapy and radiation therapy. Tamoxifen will be given for hormone receptor-positive tumors.

Larger stage IIIA as well as stage IIIB and IIIC cancers may be treated with neoadjuvant (before surgery) chemotherapy. Then a modified radical mastectomy is done, with or without reconstruction. A lumpectomy may be an option. In any case, surgery is followed by more chemotherapy and then radiation therapy even if a total mastectomy was done. Tamoxifen will be given for hormone receptor-positive tumors.

Stage IV: Systemic therapy is the primary treatment, using chemotherapy, hormone therapy, or both. Immunotherapy with trastuzumab (Herceptin) alone or in combination with chemotherapy is an option for women whose cancer cells have high levels of the HER2/neu protein. Trastuzumab is generally not the initial treatment for these women, however, and is usually started after standard hormone therapy and/or chemotherapy is no longer effective.

Radiation and/or surgery may also be used to provide relief of certain symptoms. Treatment to relieve symptoms depends on where the cancer has spread. For example, pain due to bone metastases may be treated with external beam radiation therapy and/or bisphosphonates such as pamidronate (Aredia). Bisphosphonates are drugs that can help prevent bone damage caused by metastatic breast cancer. (For more information about treatment of bone metastases, see our document "Bone Metastasis.")

Patients in otherwise good health are encouraged to take part in clinical trials of other promising treatments being studied.

Recurrent breast cancer: Breast cancer can come back locally (in the breast or near the mastectomy scar) or in a distant area.

Treatment of women whose breast cancer has recurred locally depends on their initial treatment. If the woman had breast conservation therapy, local recurrence in the breast is usually treated with mastectomy. If the initial treatment was mastectomy, recurrence near the mastectomy site is treated by removing the tumor whenever possible, usually followed by radiation therapy. In either case, hormone therapy and/or chemotherapy may be used after surgery and/or radiation therapy.

Women who have a distant recurrence involving organs such as the bones, lungs, brain, etc., are treated the same as those found to have stage IV breast cancer involving these organs at the time of initial diagnosis.

Treatment of breast cancer during pregnancy: Breast cancer is diagnosed in about 1 pregnant woman out of 3,000. Between 3% and 7% of breast cancers are diagnosed in women who are pregnant or breast feeding. Radiation therapy during pregnancy is known to increase the risk of birth defects, so it is not recommended for pregnant women with breast cancer.

For this reason, breast conservation therapy (lumpectomy and radiation therapy) is not considered an option if treatment cannot be delayed until it is safe to deliver the baby. However, breast biopsy procedures and even modified radical mastectomy are safe for the mother and fetus.

Until recently, it was assumed that chemotherapy was dangerous to the fetus. Several recent studies noted that chemotherapy during the second and third trimesters (the fourth to ninth months) does not increase the risk of birth defects or stillbirths. Because of concern about the potential damage to the fetus, the safety of chemotherapy during the first trimester (the first 3 months) of pregnancy has not been studied.

Revised 10-3-03