Carcinoma of the breast .
A malignant form of cancer that develops in breast tissue.
Causes, incidence, and risk factors
The most common type of breast cancer begins in the lining of the ducts and is called ductal carcinoma. Another type, called lobular carcinoma, arises in the lobules. For most types of breast cancer the cause is unknown.
Recently two genes, BRC1 and BRC2 have been implicated in a familial type of breast cancer. A number of other predisposing factors have been identified including obesity, early menarche, and delayed or absent child bearing. Breast cancer may occur in men as well as women, but is much more common in women. Statistics show that one in 8 or 9 American women will develop breast cancer at some point in life, based on full life expectancy.
The risk increases exponentially after age 30. The average age of women diagnosed with breast cancer is 60 years. In general, the rate of breast cancer is lower in underdeveloped countries and higher in more affluent countries (with the exception of Japan where the rate is quite low). In the U.S., whites (especially those of northern European descent) have a higher incidence compared to non-whites. However, the incidence in non-whites, specifically blacks, is increasing, particularly in women under age 60.
Other risk factors include having a family history of breast cancer, particularly in mother or siblings; a past medical history of breast cancer , ovarian cancer, uterine cancer, or colon cancer; early menarche (start of menstruation before age 12) and/or late menopause (after age 55); no pregnancies or a first Pregnancy after age 30; and radiation exposure. Post-menopausal estrogen therapy and oral contraceptive use (such as estrogens and progestin oral contraceptives) were considered possible risk factors, but the majority of recent studies do not confirm such risk.
Research suggests that a person’s diet may affect the chances of getting some types of cancer. Breast cancer appears to be more likely to develop in women whose diet is very high in fat. Older women who are overweight also seem to have a greater risk. Some scientists believe that a low-fat diet, eating well-balanced meals with plenty of fruits and vegetables, and maintaining ideal weight can lower a woman’s risk.
There are also studies that suggest a slightly higher risk of breast cancer among women who drink alcohol. The risk appears to go up with the amout of alcohol consumed., so women who drink should do so in moderation.
The possible link between diet and breast cancer is still under study.
Most of the associated risk factors cannot be controlled, therefore eliminating a means of primary prevention. However, secondary prevention, early detection, and appropriate treatment early in the disease process, may be promoted through routine breast self-exam beginning around age 20 and screening mammography after age 40. Additionally, current research studies are evaluating the effectiveness of the drug tamoxifen in preventing breast cancer in women with a family history of the disease. Currently, tamoxifen is used to treat people with breast cancer.
- Breast lump or breast mass noted upon breast self examination - usually painless, firm to hard, with irregular borders
- Lump or mass in the armpit
- A change in the size or shape of the breast
- Nipple discharge, abnormal
- Usually bloody or clear-to-yellow fluid
- May look like pus (purulent)
- Change in the color or feel of the skin of the breast, nipple, or areola
- Dimpled, puckered, or scaly
- Retraction, "orange peel" appearance
- Accentuated veins on breast surface
- Eventually (with late disease) skin ulceration
- Change in appearance or sensation of the nipple
- Pulled in (retraction), enlargement or itching
- Breast discomfort on one side only
- Breast enlargement on one side only
- Bone Pain
- Weight Loss
- Swelling of arm
- Breast Pain
- Breast Development in Males
Signs and Tests
An examination by the health care provider can confirm the presence of breast changes noted by the patient. The doctor can tell a lot about a lump by carefully feeling (palpation) the lump and the tissue around it. Benign lumps often feel different from cancerous ones.
- Mammography may help identify the breast mass.
- Ultrasonography can show whether the lump is solid or filled with fluid.
- Thermography may also help identify the mass.
- Needle aspiration or needle biopsy of the mass will either yield fluid indicating a cyst, or it will indicate a solid mass which may or may not be cancer.
Needle biopsy removes cells directly from the mass for evaluation (can be done in conjunction with the needle aspiration procedure). The material removed will be sent to a lab.
- Surgical biobsy removes a portion of the mass for further evaluation.
- Incision biopsy involves surgical removal of a portion of the mass for evaluation.
- Excision biopsy involves surgical removal of the entire mass for evaluation.
Stages of Breast Cancer (from the American Joint Committee on Cancer):
- Tumor less than 2 cm in diameter, nodes not involved, no distant metastasis
- Tumor less than 5 cm in diameter, nodes not fixed, no distant metastasis
- Tumor greater than 5 cm in diameter, invading the skin, or attached to the chest wall, or supraclavicular nodes noted, with no distant metastasis
- Tumor with distant metastasis
This disease may also alter the results of the following tests:
- Chest x-ray
The choice of initial treatment is based upon the extent and aggressiveness of the disease. Currently breast cancer is viewed as a systemic disease that requires both local and systemic treatment.
- Local treatment may include lumpectomy, mastectomy (partial, total, or radical with axillary dissection) and radiation therapy -- all directed at the breast and immediately surrounding tissue.
- Systemic treatment includes chemotherapy and hormonal therapy, which circulate drugs and hormones throughout the entire body in an attempt to eliminate cancer cells that may be present in distant parts of the body.
Most women receive a combination of treatments including surgery, radiation, chemotherapy, and/or hormonal therapy. Current recommendations for potentially curable breast cancer usually suggest that the best primary treatment is partial mastectomy plus axillary dissection and radiation therapy.
Chemotherapy may be used as additional, systemic treatment in patients with curable breast cancer. Hormonal adjunctive therapy includes the use of antiestrogen drugs (such as tamoxifen), which may be prescribed for individuals found to have estrogen-dependent cancers.
Lumpectomy (surgical removal of the lump) with radiation may be considered for individuals with stage 1 disease. However, axillary dissection is still recommended with the surgery.
The stress of illness can often be helped by joining a support group where members share common experiences and problems.
The clinical stage of breast cancer is the best indicator for prognosis (probable outcome). Five-year survival rates for individuals with breast cancer who receive appropriate treatment are approximately:
- 85% for stage 1
- 66% for stage 2
- 41% for stage 3
- 10% for stage 4
When the axillary lymph nodes are involved, the survival rate drops to approximately 40 to 50% at 5 years and probably less than 25% at 10 years.
Even with aggressive and appropriate treatments, breast cancer often metastasizes to distant sites such as the lungs, liver, and bones. The local recurrence rate is about 5% after total mastectomy and axillary dissection when the nodes are found not to be involved. The local recurrence rate is 25% in those with similar treatment found to have nodal involvement.
Calling your health care provider
Call for an appointment with your health care provider if:
- Symptoms of breast cancer occur
- If you are a woman, 40 years or older, and have not had a baseline mammogram performed
- If you are a woman, 35 years or older, and have a mother or sister with breast cancer, or a past medical history of prior breast cancer, uterine cancer, endometrial cancer, ovarian cancer, or colon cancer
- If you are a woman, 20 years or older, and are unfamiliar with how to perform a breast self-examination