Breast Cancer

Description

Alternative Names

Diagnosis

Breast Examination by a Health Professional. Early detection of breast cancer significantly reduces the risk of death. Every woman between the ages of 20 and 49 should have a physical examination by a health professional every one to two years. Those over 50 should be examined annually. A breast exam by a health professional can find 10% to 25% of breast cancers that are missed by mammograms. Between 6% to 46% of the lumps detected by examination are malignant. (The yield is lowest in younger women and highest in older women.)

Self-Examinations. Woman have been encouraged to perform a self-examination each month, but well-conducted studies in 2002 reported no difference in mortality rates between women who were intensively instructed in self-examination and those who were not. For one, they are difficult to perform and women are often not very proficient. Most women also stop doing them. This does not mean women should stop attempting self-examinations, but they should not replace the annual examination done by a health professional, which evidence suggests is beneficial.

Monthly breast self-exams should always include: visual inspection (with and without a mirror) to note any changes in contour or texture; and manual inspection in standing and reclining positions to note any unusual lumps or thicknesses.

Click the icon to see an image of a breast self-exam.

Mammograms

Current Recommendations for Screening. Mammograms are very effective low-radiation screening methods for breast cancer. At this time, the U.S. Preventive Services Task Force recommends screening mammograms, with or without breast examination every one to two years for all women over 40.After age 50 screening should be annual. (Women over 65 account for most new cases of breast cancer.) Women with risk factors for breast cancer, including a close family member with the disease, should consider having annual mammograms starting 10 years earlier than the age at which the relative was diagnosed. (Uninsured women or those who have not been referred to a mammogram center can contact their local American Cancer Society for available low-cost programs.)

Click the icon to see an image of a mammogram.

Issues Involved with Screening. Mammograms are not foolproof, however. In general, they still miss up to 25% of cancers (which can sometimes be caught on a physical examination). And, furthermore, between 80% and 90% of suspicious mammograms turn out to be benign. According to one study, by the time a woman has nine mammograms, she has a 43% chance of having a false-positive mammogram (one that suggests cancer that isn't really there). This means many women are requiring biopsies who do not have cancer (but the only way to be sure is to perform the biopsy). Digital mammography is a recent technique that converts the image of the breast so it can be viewed and manipulated on a computer screen. It is improving accuracy but no screening technique is perfect yet.

Even given current recommendations, there are a number of issues as to who should screen and when to screen.

For Women between Ages 50 and 60. Evidence suggests that annual mammograms save lives in this age group. Furthermore, according to one study, because regular screening tends to find cancers in earlier stages there has also been a decline in the number of mastectomies (surgical removal of the breast).

For Women between Ages 40 and 49. Whether premenopausal women should have routine mammograms is controversial. The areas of debate are as follows:

• Arguments against Regular Screening. A number of studies have now reported that any survival benefits from regular mammography in this group are likely to be small compared to breast examinations alone. Most of the arguments against mammography in this population are due its inefficiencies in this age group. The probability that woman in this age group with a suspicious mammogram will actually have breast cancer is only 2% to 4%; so frequent screening becomes very cost-inefficient and produces many unnecessary biopsies. In addition, breast tissue is dense in premenopausal women and mammography often fails to detect breast cancers that are present. Breast cancers in this age group are also often aggressive and two-year intervals may not detect them early enough to affect survival.
• Arguments for Regular Screening. Breast cancer fatality rates are highest in women between ages 40 and 49. And in spite of some negative studies, recent ones are finding some survival benefits for screening every one or two years. Advances in imaging techniques are helping to improve accuracy.

For Women Over 69. Most breast cancers appear in women over 70 and such women are more likely to be diagnosed at a later stage, most often because of less frequent screenings. Still, experts disagree about the benefits of regular screening in older women. Some evidence suggests that regular screening would prevent only about one death per 1,000 women screened. Elderly women are also particularly likely to have non-malignant abnormalities in their breasts and so undergo unnecessary biopsies.

Other Imaging Techniques

Magnetic Resonance Imaging (MRI) and Ultrasound. MRI and ultrasound techniques can detect very small tumors (less than half an inch). However, they are expensive and are time-consuming procedures. Nevertheless, some experts believe they are important in identifying small tumors missed on mammography in women who are receiving lumpectomy or breast-conserving surgeries. Such findings would allow the surgeons to remove the optimal amount of abnormal tissue. Ultrasound may also be particularly important for women with dense breast tissue who show signs of breast cancer.

Scintimammography. Scintimammography employs a radioactive chemical injected into the circulatory system, which is then selectively taken up by the tumor and revealed on mammograms. This method is very accurate in detecting the presence or absence of breast cancer, and some experts hope that it might eventually reduce the number of unnecessary invasive biopsies.

Biopsy

A definitive diagnosis of breast cancer can be made only by a biopsy (a microscopic examination of a tissue sample of the suspicious area).

• When a lump can be felt and is suspicious for cancer on mammography, an excisional biopsy may be recommended. This biopsy is a surgical procedure for removing the suspicious tissue and typically requires general anesthetic.

Click the icon to see an image of breast biopsy.

• A core biopsy involves a small incision and the insertion of a spring-loaded hollow needle that removes a number of samples. The patient only requires local anesthetic.
• A wire localization biopsy may be performed if mammography detects abnormalities but there is no lump. With this procedure, using mammography as a guide, the physician inserts a small wire hook through a hollow needle and into the suspicious tissue. The needle is withdrawn and the hook is used by the surgeon to locate the lesion and to remove it. The patient may be given local or general anesthetic.
• A new vacuum-assisted device may be useful for some biopsies. This employs a single probe through which a vacuum is used to draw out tissue. It allows several samples to be taken without having to remove and re-insert the probe.

Final analysis of the breast tissue may take several days.

Lymphadenectomy

If breast cancer has been determined, the next diagnostic step is to find out how far it has spread. To do this, the physician performs a procedure called an axillary lymphadenectomy, which partially or completely removes the lymph nodes in the armpit beside the affected breast (called axillary lymph nodes). It may require a hospital stay of a day or two.

Click the icon to see an image of the axillary lymph nodes..

Once the lymph nodes are removed, they are analyzed to determine whether subsequent treatment needs to be more or less aggressive:

• If no cancer is found in the lymph nodes, then the condition is referred to as node negative breast cancer. The chances are good, then, that the cancer has not spread and is still local.
• If cancer cells are present in the lymph nodes, the cancer is called node positive. Their presence increases the possibility that the cancer has spread microscopically to other areas of the body. In such cases, however, it is still not known if the cancer has metastasized beyond the lymph nodes or, if so, to what extent. The physician may then perform further tests to see if the cancer has spread to the bone (bone scan), lungs (x-ray or CT scan) or brain (MRI or CT scan).

Side effects of the procedure include increased risk for infection and pain, swelling in the arm from fluid build-up, and impaired sensation and restricted movement in the affected arm. Patients might ask their physician about the availability of physical therapy or upper-body exercises after treatment. In two studies, such programs resulted in quicker recovery and no fluid build-up in the arm.

Sentinel Node Biopsy

A technique known as a sentinel node biopsy is increasingly performed by experienced surgeons in selected patients. This procedure is used to determine if cancer has spread beyond the nodes and so possibly reduce the need for complete axillary lymphadenectomies.

Click the icon to see an image of a sentinel node biopsy.

It involves the following:

• The procedure uses an injection of a tiny amount of a tracer, either a radioactively-labeled substance (radioisotope) or a blue dye, into the tumor site.
• The tracer or dye then flows via the lymphatic system into the so-called sentinel node. This is the first lymph node to which any cancer would spread.
• The sentinel lymph node and possibly one or two others are then removed.
• If they do not show any signs of cancer, it is highly likely that the remainder of the lymph nodes will be cancer free, and further surgery becomes unnecessary.

It is still not known if the sentinel node biopsy has any survival advantages compared to the standard procedures with lymph nodes removal.