A diagnosis of breast cancer can be established only by a biopsy and microscopic examination, although less invasive techniques like mammography and palpation may provide valuable information.
Several types of biopsy techniques are used but, increasingly, needle aspiration is being recommended for women whose breasts can be examined this way.
The technique entails using a hypodermic needle and syringe to remove a small piece of tissue from the breast mass, which is then examined microscopically. This technique is 96 percent accurate (the errors are almost invariably false negative results in which the needle has missed the tumor). Needle biopsies can be performed in a physician’s office or outpatient clinic using only a local anesthetic. This technique has several advantages over a surgical biopsy: It is less costly, does not involve as much discomfort, and has a lower risk of wound infection in the biopsy site. Also, the biopsy incision may interfere with optimal placement of the surgical incision if a later mastectomy is performed.
There are, however, situations in which a needle biopsy is not appropriate. Women who have large breasts with a small lump near the chest wall are not good candidates for this procedure. The same applies to women who have a suspicious area that shows up on a mammogram but cannot be felt.
Surgical, or excisional, biopsies involve removing the lump, usually as an outpatient procedure using local anesthesia unless it is being done at the same time as the treatment. Depending upon individual circumstances and preferences, a typical diagnosis/treatment program might be as follows:
- A lump or other suspicious sign is discovered, either by the woman or her physician.
- The woman undergoes an examination, which includes mammography.
- Unless the lesion clearly is not cancer, an aspiration biopsy will be performed or the lump will be surgically removed.
- If the results are positive, the woman and her physician will discuss the treatment options and decide what the next steps should be. A second opinion may be sought at this time. Although the aspiration biopsy is highly accurate, most surgeons do not do a mastectomy based on it alone. As a general policy, a surgical excisional biopsy will be done and if it too is positive, the definitive treatment will follow at that time. This differs from the previous one-step procedures in which a positive surgical biopsy was immediately followed by mastectomy in that the woman and her physician already have had an opportunity to discuss the diagnosis and treatment based on the aspiration biopsy. In the old one-step procedure, the woman would not know the diagnosis in advance of the definitive operation.
- If the results of the aspiration biopsy are negative but there are other signs that the lump may be cancer, a surgical biopsy will be performed. This may or may not be done as part of a one-step procedure, based on the woman’s preference.
There are, of course, variations and exceptions to this approach. Over the last decade there has been considerable disagreement among both doctors and patients over what is the best way to approach breast cancer. Until a decade ago diagnosis and treatment were usually carried out at the same time. The woman would enter the hospital, and the biopsy would be performed under general anesthesia. The suspicious tissue would be sent immediately to the pathology lab for diagnosis. If it turned out to be cancer, the surgeon would then proceed with treatment, which usually meant a mastectomy. Thus a woman going into an operating room for a biopsy would not know whether she would wake up and find she had undergone a mastectomy. Today, women undergoing treatment for breast cancer almost always have the diagnosis established beforehand. Typically, a needle biopsy will be performed. If it is positive, the woman and her physician will discuss treatment options.
An excisional biopsy to confirm the diagnosis will then be incorporated into the treatment. This gives the woman and those close to her time to adjust to the diagnosis before undergoing immediate treatment. Before the advent of outpatient biopsies using local anesthesia, the need to undergo two operative procedures using general anesthesia had been a major argument against the two-stage approach.
Today there are more treatment options, and women are more involved in deciding what is best for them. There are pros and cons for both approaches, and these should be fully discussed by the woman, her physician, and her family members. Arguments for the two-stage approach include:
Most often, suspicious lumps turn out to be benign, especially in younger women. The two-stage procedure spares these women the risk and cost of general anesthesia and the mental anguish of not knowing whether they will emerge from the operating room minus a breast.
- The pathologic diagnosis in a two-stage procedure involves mounting the tissue on a slide and studying it microscopically. These are called “permanent sections”; the slides may be submitted for a second opinion.
- A two-stage procedure allows time for other tests, such as an estrogen and progesterone receptor test of the cancer, or bone and liver scans to determine whether the disease has spread, before treatment is undertaken.
- A woman can seek a second opinion or discuss treatment options with her doctor following the diagnosis. Plans also can be made for possible breast reconstruction before the mastectomy.
- Supporters of the one-step procedure point to the following facts:
- Some women find the time between biopsy and diagnosis, and between diagnosis and treatment extremely stressful.
- Frozen sections are 98 percent as accurate as permanent sections and, as noted above, most errors are false negatives. Instances in which a mastectomy would be performed based on a false positive frozen section would be very rare, contrary to some reports in the popular media.
- The one-step procedure avoids the risk of infection in the biopsy wound.
- In some cases—when the tumor is deep within the breast, or so small that it requires X-ray studies to locate it, or when the breasts are very large or the patient very apprehensive—general anesthesia is necessary for the biopsy. In these cases there may be no need to subject the patient to general anesthesia twice if she is agreeable to a one-step procedure.
The woman in whom breast cancer is suspected should consider all factors carefully before deciding which approach to diagnosis and treatment she wants. A week or two of delay between diagnosis and definitive treatment will probably do no harm. If the patient opts for the two-step procedure, she should take the time to find a physician who will perform it and not fear a short interval between diagnosis and treatment. An extended interval is usually not advised because some types of breast cancer may spread rapidly.
The woman who is having a breast biopsy under local anesthesia as an outpatient in a hospital or doctor’s office is usually asked not to eat anything after midnight of the day before. Before the biopsy, she will be given an injection of a local anesthetic into the biopsy area. After the anesthetic takes effect, the surgeon proceeds with the biopsy. The suspicious lump and a small amount of surrounding tissue is usually removed.
The mammograms may be used to help locate the area to be removed. In instances in which a suspicious area shows up on a mammogram but is too small to be felt, an additional procedure may be needed to enable the surgeon to locate the area. This may involve using a preoperative X-ray examination to guide injection of a dye into the area to be removed. Alternatively, a needle may be inserted into the area, again using X rays for guidance. These various procedures help ensure that the suspicious area is accurately located, and only a minimal amount of tissue removed, thus minimizing disfigurement of the breast. Following removal of the lump, the wound will be closed.
For biopsy under general anesthesia, the woman may undergo tests on an outpatient basis before hospital admission for premedication and the biopsy, which is performed in an operating room. If a one-stage procedure has been agreed upon by the woman and her physician, a frozen section examination of the removed tissue will be performed while the patient is still anesthetized. If the biopsy shows no cancer, the incision is closed and the woman can generally return home later the same day or the next day. If the biopsy shows cancer, the surgeon will then proceed to the more extensive operation if this is what both the patient and the surgeon have agreed upon in advance.