What's a breast biopsy?
A breast biopsy is a procedure in which a doctor removes a small amount of tissue or fluid from your breast in order to examine it under a microscope for signs of cancer. Your doctor will usually recommend a biopsy if there's a lump in your breast or something suspicious on your mammogram or ultrasound scan. About 80 percent of biopsies show that no cancer is present. If the mass seems likely to be harmless, you may be given the option of waiting a few months instead to see whether anything changes. Ask lots of questions and trust your instincts.
What can the doctor tell from looking at my tissue sample?
By examining your cells, a pathologist can tell whether they're cancerous and, if so, roughly how advanced the cancer is. Further lab tests may reveal more about the cancer -- whether its cells will respond to hormone treatment, for instance (this happens more frequently in postmenopausal women).
How is a biopsy done?
The type of biopsy you'll have depends on the size, number, and location of the lumps that have been discovered. Your doctor may recommend a fine-needle aspiration first, since it's the least invasive of the lot, can be done in the doctor's office, and requires only local anesthesia. The doctor inserts a very thin needle attached to a syringe into the lump to see if it's solid or filled with fluid. (If the lump is hard to locate, the doctor may use an ultrasound to guide the needle into the mass.) If there's clear fluid inside the mass, it's probably a harmless benign cyst, but it should be analyzed just to make sure. In rare cases, bloody or cloudy fluid may mean cancer. If the mass is solid, and the pathologist finds no cancer cells, the tumor must be investigated further because cancer cells may have been missed. A further biopsy in which more tissue is removed is always necessary just to make certain the tumor is cancer-free.
In a core-needle biopsy, the doctor uses a thicker needle (about 1/16 to 1/8 inch in diameter) to remove a larger amount of tissue. This is also an outpatient procedure that requires only local anesthesia. It will probably take the lab about two days to complete an analysis of your sample. Two methods that remove more tissue than a core biopsy are called Mammotome and ABBI (Advanced Breast Biopsy Instrument).
In some cases, the doctor will want to do a more thorough examination by surgically removing a larger portion of the lump (this is called an incisional biopsy) or by taking out the entire lump and some surrounding tissue (this is known as an excisional biopsy or lumpectomy). Both procedures are normally done on an outpatient basis, but in a hospital rather than a doctor's office. To make things easier, your doctor may use a technique called wire localization, in which x-rays help show where a hollow needle should be inserted so that it will pierce the lump. Once the needle is in place, a wire with a tiny hook on the end is passed through it and planted in the mass. Then the needle is removed, and the wire serves as a guide to the lump.
If your doctor suspects that you have inflammatory breast cancer, he or she may do what's called a punch biopsy on the skin of your breast, using a cylindrical needle 3 or 4 millimeters in diameter. This outpatient procedure requires only local anesthesia.
Will a biopsy leave a scar?
The more invasive a biopsy is, the more of a scar it will leave. Scar tissue inside the breast may harden and feel lumpy. An incisional biopsy that removes part of a lump will leave behind not only a scar but also the rest of the lump. As the tissue heals, ask your doctor how to tell the difference between scar tissue and a new lump when you do your breast self-exams .
Remember, too, that the vast majority of biopsies turn out benign, but the earlier a biopsy catches a cancer tumor, the more likely a woman is to overcome it.
American Cancer Society. Breast Cancer: Detection and Symptoms.
Beth Israel Hospital. Breast Cancer Guide: Making a Diagnosis
Breast Cancer: The Complete Guide by Yashar Hirshaut, M.D. and Peter Pressman, M.D., Bantam Books.
American Cancer Society. How is Breast Cancer Diagnosed?