Staging and Survival Rates of Breast Cancer

• What is Staging?
• Numerical Stages of Breast Cancer
• Breast Cancer Survival Rate by Stage
• Inflammatory Breast Cancer
• Paget’s Disease of the Nipple
• Recurrence of Breast Cancer
• Additional Resources and References

What is Staging?

Staging is the process physicians use to assess the size and location of a patient’s cancer. Identifying the cancer stage is one of the most important factors in selecting treatment options. Several tests may be performed to help stage breast cancer including clinical breast exams, biopsy, and certain imaging tests such as a chest x-ray, mammogram, bone scan, CT scan, and MRI scan. Blood tests are used to evaluate a woman's overall health and detect whether the cancer has spread to certain organs often follow imaging tests.

To stage cancer, the American Joint Committee on Cancer first places the cancer in a letter category using the TNM classification system. Cancers are designated the letter T (tumor size), N (palpable nodes), and/or M (metastasis):

T: Tumor Size

The letter T followed by a number from 0 to 4 describes the tumor's size and whether it has spread to the skin or chest wall under the breast. Higher T numbers indicate a larger tumor and/or more extensive spread to tissues surrounding the breast.

• TX: Tumor cannot be assessed
• T0: No evidence of a tumor
• Tis: Cancer may be lobular carcinoma in situ (LCIS), ductal carcinoma in situ (DCIS) or Paget’s disease)
• T1: Tumor is 2 cm or less in diameter
• T2: Tumor is between 2 and 5 cm in diameter
• T3: Tumor is more than 5 cm in diameter
• T4: Tumor is any size, has attached itself to the chest wall and spread to the pectoral (chest) lymph nodes

N: Palpable Nodes

The letter N followed by a number from 0 to 3 indicates whether the cancer has spread to lymph nodes near the breast and, if so, whether the affected nodes are fixed to other structures under the arm.

• NX: Lymph nodes cannot be assessed (lymph nodes were previously removed, etc.)
• N0: Cancer has not spread to lymph nodes
• N1: Cancer has spread to the movable ipsilateral axillary lymph nodes (underarm lymph nodes on same side of breast cancer)
• N2: Cancer has spread to ipsilateral (same side of body as breast cancer) lymph nodes fixed to one another or to other structures under the arm
• N3: Cancer has spread to the ipsilateral mammary lymph nodes or the ipsilateral (same side of body as breast cancer) supraclavicular lymph nodes

M: Metastasis

The letter M followed by a 0 or 1 indicates whether or not the cancer has metastasized (spread) to distant organs (i.e., the lungs or bones) or to lymph nodes that are not next to the breast, such as those above the collarbone.

• MX: Metastatis cannot be assessed
• M0: No distant metastasis to other organs
• M1: Distant metastatis to other organs

Numerical Stages of Breast Cancer

The stage of a breast cancer describes its size and the extent to which it has spread. The staging system ranges from Stage 0 to Stage IV.

Stage 0 or "in situ," Tis, N0, M0 or "in situ:" The term "in situ" literally means "in place." Stage 0 cancer is a contained cancer that has not spread beyond the breast ductal system. Fifteen to twenty percent of breast cancers detected by clinical examinations or testing are in Stage 0 (the earliest form of breast cancer). Two types of Stage 0 cancer are lobular carcinoma in situ (LCIS) and ductal carcinoma in situ (DCIS).

• LCIS: indicates high risk for breast cancer. Many physicians do not classify LCIS as a malignancy and often encounter LCIS serendipitously (by chance) on breast biopsy while investigating another area of concern. While the microscopic features of LCIS are abnormal and are similar to malignancy, LCIS does not behave as a cancer (and therefore is not treated as a cancer). LCIS is merely a marker for a significantly increased risk of cancer anywhere in the breast. However, bilateral simple mastectomy may be occasionally performed if LCIS patients have a strong family history of breast cancer. More likely, LCIS patients are closely monitored with physician performed clinical breast exams every four months in addition to yearly mammography. Some patients may be given the drug tamoxifen to help prevent the development of breast cancer.
• DCIS: the cancer cells are confined to milk ducts in the breast and have not spread into the fatty breast tissue or to any other part of the body (such as the lymph nodes). DCIS may be detected on mammogram as tiny specks of calcium (known as microcalcifications) 80% of the time. Less commonly DCIS can present itself as a mass with calcifications (15% of the time); and even less likely as a mass without calcifications (less than 5% of the time). Breast biopsy is used to confirm DCIS. Standard DCIS treatment is breast-conserving therapy (BCT): lumpectomy followed by radiation treatment or mastectomy. To date, DCIS patients have chosen equally among lumpectomy and mastectomy as their treatment option, though specific cases may sometimes favor lumpectomy over mastectomy or vice versa. Click here for more information on how to treat DCIS.

Stage I ,T1, N0, M0:: The primary (original) cancer is 2 cm (approximately 4/5 inch) or less in diameter and has not spread to the lymph nodes. Stage I breast cancer treatment usually consists of:

• Breast conserving therapy (BCT): lumpectomy (removal of cancerous lump and Small margin of surrounding normal tissue) and axillary node dissection (removal of underarm lymph nodes) followed by radiation

• Or modified radical mastectomy (removal of the affected breast) and axillary node dissection.  Click here for more information on mastectomy.

Stage IIA: T0, N1, M0 / T1, N1, M0 / T2, N0, M0: No tumor is found in the breast but it is in 1 to 3 underarm lymph nodes, or the tumor is less than 2 cm and has spread to 1 to 3 underarm lymph nodes or found by sentinel node biopsy as microscopic disease in internal mammary nodes but not on imaging studies or by clinical exam, or the tumor is larger than 2 cm in diameter and less than 5 cm but hasn't spread to underarm nodes. The cancer has not spread to distant sites.

Stage IIB: T2, N1, M0 / T3, N0, M0: The tumor is larger than 2 cm in diameter and less than 5 cm and has spread to 1 to 3 undearm lymph nodes or found by sentinel node biopsy as microscopic disease in internal mammary nodesor the tumor is larger than 5 cm and does not grow into the chest wall and has not spread to lymph nodes. The cancer has not spread to distant sites.

Common treatment for Stage II breast cancer is usually the same as Stage I treatment (lumpectomy and axillary node dissection or modified radical mastectomy), though radiation therapy is often necessary if the tumor is large or has already spread to the lymph nodes.

Stage IIIA:

Stage IIIA: T0-2, N2, M0 / T3, N1-2, M0: The tumor is smaller than 5 cm in diameter and has spread to 4 to 9 undearm lymph nodes or found by imaging studies or clinical exam to have spread to internal mammary nodes, or the tumor is larger than 5 cm and has spread to 1 to 9 axillary nodes or to internal mammary nodes. The cancer hasn't spread to distant sites.

Stage IIIB: T4, N0-2, M0: The tumor grown into the chest wall or skin and may have spread to no lymph nodes or as many as 9 underarm nodes. It may or may not have spread to internal mammary nodes. The cancer has not spread to distant sites.

Stage IIIB treatment often begins with neoadjuvant chemotherapy to reduce the tumor’s size. Lumpectomy or modified radical mastectomy followed by chemotherapy, radiation, or chemotherapy plus hormonal therapy are standard treatments.

Stage IV: The primary cancer has spread out of the breast to other parts of the body (such as bone, lung, liver, brain). The treatment of Stage IV breast cancer focuses on extending survival time and relieving symptoms. Systemic treatment (treatment that affects the entire body) such as chemotherapy, hormonal therapy or both is often recommended. Radical mastectomy or the use of the drug tamoxifen may provide symptom relief in some cases.

Source: American Cancer Society

Source: American Joint Commission on Cancer and International Union Against Cancer

Breast Cancer Survival Rate by Stage

Health care professionals are able to be predict a patient’s survival rate based on the determined stage of breast cancer. The following chart is an approximate survival rate for each stage of breast cancer. Percentages will vary depending on individual medical situations, etc.

Source: American Cancer Society

A five-year survival rate refers to the average number of patients who are still alive five years after diagnosis with a specific stage of breast cancer. Five-year survival rates do not include patients who die from other causes. After seven years, the survival rate decreases for each stage.

It is important to remember that these survival rates are based on averages. Some women with advanced breast cancer live significantly longer than seven years. Researchers are constantly developing new treatment alternatives to prolong breast cancer survival.

Inflammatory Breast Cancer

Inflammatory breast cancer is the appearance of inflamed breasts (red and warm) with dimples and/or ridges caused by the infiltration of tumor cells into the lymphatics. Inflammatory breast cancer can sometimes be difficult to distinguish between benign (non-cancerous) conditions (such as mastitis) and inflammatory malignancy (cancerous conditions). Though rare, inflammatory breast cancer may spread quickly to other parts of the body.

Treatment of inflammatory breast cancer treatment is generally quite similar to the treatment of Stage IIIB or IV breast cancer. In addition, patients usually undergo chemotherapy, hormonal therapy and/or radiation treatment. Patients who respond positively to systemic treatment may be candidates for mastectomy.

Paget’s Disease of the Nipple

Paget’s disease of the nipple is a rare form of breast cancer that begins in the milk ducts and spreads to the skin of the nipple and areola. The skin may appear crusted, red, or oozing. Prognosis is better if nipple changes are the only sign of the breast disease and no lump is felt.

Recurrence of Breast Cancer

Women who experience a recurrence of breast cancer after lumpectomy are often treated simply by mastectomy (with or without breast reconstruction).

If cancer reoccurs after mastectomy, additional surgery may be necessary to remove tumors near the mastectomy site, followed by radiation therapy. Chemotherapy and/or hormonal therapy may also be administered.

Alternative treatment options for recurrent breast cancer include:

• Hormone therapy
• Surgery and/or radiation therapy if cancer is confined to one area and is operable
• Entry into a clinical trial testing new chemotherapy or hormonal drugs, or biological therapy

Removal of the ovaries (oophorectomy) is also a possible treatment option for recurrent breast cancer, though the procedure is rarely performed in the United States.

Additional Resources and References

• The American Cancer Society's provides detailed information on breast cancer staging available at http://www.cancer.org/.

May 4, 2008