For Women Facing a Breast Biopsy

+ -Text Size


Diagnostic tests for breast conditions

The 2 main tests used to diagnose breast conditions are mammograms and ultrasound. Magnetic resonance imaging (MRI) is used in some cases, usually along with one of the other 2 tests.

More details on these and other imaging tests used to diagnose breast changes can be found in another one of our documents called Mammograms and Other Breast Imaging Procedures.

Diagnostic mammogram

If a woman has noticed breast changes or symptoms, or if a routine screening mammogram has found a suspicious-looking area, she may need to get a diagnostic mammogram. During a diagnostic mammogram, more x-rays are taken of the breast than during a screening mammogram. Extra pictures are focused on the area of concern.

Mammograms are usually a black-and-white picture of the breast tissue on a large sheet of film that is read, or interpreted, by a radiologist (a doctor specially trained to read these kinds of tests). For a mammogram, the breast is pressed between 2 plates to flatten and spread the tissue. This may be uncomfortable, but it’s needed to get a good, clear picture. The pressure only lasts a few seconds. The entire mammogram procedure takes about 20 minutes.

A digital mammogram is done the same way, but it’s another option. A digital mammogram produces computer images instead of film. These images can be read on a computer screen and saved in the system. The images can be looked at from different angles. The radiologist can enlarge the pictures and zoom in to look at any suspicious areas.

But mammograms alone cannot prove that an abnormal area is cancer. Tissue from the area must be taken out and looked at under a microscope. This is called a biopsy. Breast cancer cannot be diagnosed without a biopsy.

You should also know that a mammogram is not perfect at finding breast cancer. If you have a breast lump, you should have it checked by your doctor and talk about having a biopsy even if your mammogram is normal.

Breast ultrasound

Breast ultrasound uses sound waves to make a computer picture of the inside of the breast. This test is sometimes used to target a certain area of concern that was found on the mammogram or physical exam.

Ultrasound is useful for looking at some breast changes, such as those that can be felt but not seen on a mammogram. It also helps tell the difference between fluid-filled cysts and solid masses. If a lump is really a cyst, it’s benign (not cancer). If this is the case, your doctor may not have to put a needle into it to take out fluid.

Ultrasound uses high-frequency sound waves to outline a part of the body. The sound waves are sent into the area of the body being studied and echoed back. These echoes are picked up by the ultrasound probe. A computer changes the sound waves into a picture that is shown on a screen. Radiation is not used to do this test.

Magnetic resonance imaging

Magnetic resonance imaging (MRI) is sometimes used to look for breast cancer in women who are known to be at high risk. It may also be used to get a closer look after breast cancer has been found. An MRI can show if your lymph nodes are enlarged, which may be a sign that they contain cancer. (Lymph nodes are small bean-shaped collections of immune system tissue that are connected by small vessels or tubes. They remove cell waste, germs, and other harmful substances from the body. Cancers sometimes spread into them or through them.)

MRI is sometimes used to look for breast tumors that did not show up on the mammograms. It’s also used to help guide the biopsy needle into tumors that can’t be seen on mammograms. This is known as MRI-guided biopsy. (You can read more about this under “Vacuum-assisted core biopsies” in the section called “Types of biopsy procedures.”)


Ductograms are sometimes used to find the cause of nipple discharge. A ductogram is also called a galactogram.

In this test, a small amount of dye is put into one of the ducts in the nipple through a tiny plastic tube. The dye can be seen on an x-ray, which can then show if there is a mass inside the duct.


Even though imaging tests like the mammogram and ultrasound can find a suspicious area, they cannot tell whether it’s cancer. A biopsy is the only way to tell for sure if a breast change is cancer.

A biopsy removes some cells from the area of concern so they can be checked under a microscope. The cells can be removed using a needle or by doing surgery to take out part or all of the tumor. The type of biopsy depends on the size and location of the lump or suspicious area.

If your doctor thinks you don’t need a biopsy, but you feel there’s something wrong with your breast, follow your instincts. Don’t be afraid to talk to your doctor about this or go to another doctor for a second opinion.

    A biopsy is the only sure way to diagnose breast cancer.

Second opinions

Even before you have a biopsy, you might want to get a second opinion. This way, another expert from another hospital or mammogram center will look at your mammogram. You can ask your doctor to set this up for you, or you can have the films sent to an expert you have chosen. If you have had a digital mammogram, the images can be sent electronically, but you may still need to send your older films to compare.

Your doctor’s office staff can help you figure out what you need to do and how to do it. They should send your most recent mammogram and any older ones they have to a center that specializes in mammograms and the diagnosis of breast cancer. Or, if the facility will make copies, you can take them for a second opinion yourself. Be sure to find out ahead of time if the second facility or doctor accepts copies; some facilities read only original x-rays. You should also find out if your health insurance will pay for a second opinion. If not, you will want know what your costs will be.

It takes great skill and experience to read a mammogram, either from film or from a digital picture. Be sure your mammogram is being read by an expert.

Last Medical Review: 07/13/2012
Last Revised: 07/13/2012