The process of diagnosis includes the following:

Review of Your Medical History

Your doctor will review your medical history, and will ask you about certain factors that can affect your risk for breast cancer. These include a family history of breast or other cancers; your reproductive history, including your age at first period and age at first pregnancy (if applicable); and your lifestyle habits, such as exercise, weight history, and alcohol intake.

Physical Exam

Your doctor will do a thorough physical exam, including a breast exam. Your breasts will be examined for symptoms characteristic of cancer, which include the following:

  • Lumps or thickening in or near the breast, or in the underarm area
  • Nipple discharge or inverted nipple
  • Redness or changes in the skin or contour of the breast, areola (the circular pigmented area surrounding the nipple), or nipple
  • Ridges or pitting of the breast (the skin looks like the skin of an orange)

Testing

If breast cancer screening is recommended, or if a breast cancer is suspected, the following tests may be done:

Mammogram

A mammogram is a special x-ray of the breast that can often find tumors that are too small for you or your doctor to feel. Mammograms are usually done in a clinic or special radiology center; the test itself will only take about 15 minutes to complete. The ability of mammography to detect cancer depends on such factors as the size of the tumor, the age of the woman, breast density, and the quality of the imaging center. Breasts that are dense can be more difficult to study with a mammogram.

Although the mammogram is the most cost effective screening tool currently used to evaluate the breast, it will miss 10% to 15% of breast cancers. Other x-rays, including MRIs, are being studied to see if they are more accurate than mammograms in detecting cancer.

During a mammogram, you will remove all clothing above the waist, and will sit upright in front of a mammography machine. You will be provided with a lead vest to cover and protect your reproductive organs. A technician will position and compress each breast between two plates on the x-ray machine so an accurate picture can be taken. A radiologist will examine the x-ray for any potential abnormalities.

The results of your mammogram should be reported to you and to your doctor. If for some reason you are not contacted, call your doctor to request the results. If the test results are suspicious or inconclusive, you may be asked to have other testing procedures, such as an ultrasound.

Ultrasonography

Ultrasound is the use of high-frequency sound waves to evaluate lumps that have been identified via breast self-exam, clinical breast exam, or mammography. Lumps can be identified as tumors, which are solid, or cysts, which are filled with fluid. Solid masses and cysts that are not completely smooth may require further evaluation. Ultrasound is very helpful as an aid to guide biopsy. This is a painless test.

For an ultrasound, you will lie down, and a technician will apply a sound-conducting jelly to the skin of your chest. The ultrasound machine has a hand-held instrument called a transducer, which looks like a microphone or wand. The transducer is passed over the skin where the jelly was applied. The transducer sends high-frequency sound waves into the body, which bounce off the internal organs and echo back to the transducer. The echoes are converted to images (each image is called a sonogram) that are displayed on a screen. The doctor examines the images on the screen and may make a photograph for further assessment.

Magnetic Resonance Imaging (MRI)

An MRI is a test that uses magnetic waves to produce images of the breast and identify abnormalities. Using a large magnet, radio waves, and a computer, an MRI produces two-dimensional and three-dimensional pictures. The use of MRI to diagnose breast cancer is very controversial and is under study at many medical centers. In some cases MRI may be helpful in determining if a mass has benign features. Ask your doctor if MRI could be of use for you.

At this time, MRI is not considered a substitute for mammography.

For the MRI, you will lie very still face down on a sliding table. The table is slid into the MRI's narrow, enclosed cylinder (unless it is an "open" MRI). The MRI technician leaves the room, and each of the MRI sequences is performed. Via an intercom, the technician gives you any necessary directions, such as to hold your breath momentarily. You are able to talk to the technician through this intercom as well.

If a contrasting dye (usually Gadolinium) is needed, a small IV needle is inserted into your hand or arm before you are slid into the MRI machine. First, a saline solution is dripped into your vein to prevent clotting. Then, usually two-thirds of the way through the exam, the contrasting agent is injected.

When the MRI exam is completed, you are slid out of the machine, the IV needle is removed, and you are asked to dress and wait in the waiting room until MRI images can be checked to be sure no additional images are necessary.

Further Testing

Depending on the outcome of the first set of tests, your doctor may decide to continue to monitor subsequent breast changes, or to do further testing. In some cases, your doctor may remove a sample of tissue (biopsy) to be examined in the lab. This sample may be taken by one of the following methods:

  • Fine needle aspiration – a thin needle is used to remove fluid and/or cells from a breast lump. If the fluid is clear, it may not need to be checked by a lab.
  • Large needle (or core) biopsy – tissue is removed with a large-bore needle from an area that looks suspicious on a mammogram or ultrasound, but cannot be felt.
  • Surgical biopsy – all or part of a breast lump is removed for lab examination:
    • Incisional biopsy – a small portion of a large lump is removed
    • Excisional biopsy – the entire lump (usually a small lump) is removed
  • Ductal lavage – fluid is injected into the milk duct and then collected for analysis. The use of ductal lavage to help diagnose breast cancer is still under study.

After you receive your test results, your doctor will tell you if your tissue biopsy is benign (non-cancerous) or malignant (cancerous). Benign breast tumors, such as fibroadenomas or papillomas, do not spread outside of the breast and usually require no further treatment once diagnosed.

If your test results indicate that the tumor is malignant, more tests will be conducted on the biopsy specimen to determine the stage, which is a description of how far the cancer has progressed. The most common type of breast cancer is ductal carcinoma, which begins in the cells of the ducts. Cancer that begins in the lobes or lobules is called lobular carcinoma and is more often found in both breasts than are other types of breast cancer.

Staging

If cancer is found, your prognosis and treatment depend on the location, size, and stage of the cancer and your general health.

Staging is the process by which physicians determine the prognosis of a cancer that has already been diagnosed. Staging is essential for making treatment decisions (e.g., surgery vs. chemotherapy). Several features of the cancer are used to arrive at a staging classification, the most common being the size of the original tumor, extent of local invasion, and spread to distant sites (metastasis). Low staging classifications (0–1) imply a favorable prognosis, whereas high staging classifications (4–5) imply an unfavorable prognosis.

The following stages are used to classify breast cancer:

Stage 0In situ (within the site of origin) – the cancer remains in the breast and has not spread. The two types of in situ cancer include:

  • Ductal carcinoma in situ (DCIS) – a very early breast cancer that may develop into an invasive type of breast cancer. Invasive cancers are those that spread from the duct into surrounding tissues.
  • Lobular carcinoma in situ (LCIS) – this is not cancer, but rather a marker that identifies a woman as having an increased risk of developing invasive breast cancer. Invasive cancers are those that spread from the duct into surrounding tissues. It is common for both breasts to be affected.

Stage I – cancer has spread beyond the lobe or duct and invaded nearby tissue. At this stage, the tumor is no larger than 2 centimeters (cm) in size, and has not spread beyond the breast.

Stage II – this stage has two levels:

  • Stage IIA – this stage can occur in three different cases:
    • The tumor in the breast is greater than 2 cm but not more than 5 cm and no lymph nodes are involved
    • The tumor is less than 2 cm in size and the cancer has spread to the lymph nodes under the arm
    • The tumor is less than 2 cm in size and the cancer has spread to the lymph nodes under the breast bone (internal mammary nodes)
  • Stage IIB - this stage can occur in two different cases:
    • The tumor is between 2 cm and 5 cm in size, with spread to the lymph nodes under the arm and in certain cases the internal mammary nodes
    • The tumor is larger than 5 cm but has not spread to the lymph nodes

Stage III – this stage has three levels:

  • Stage IIIA - this stage can occur in four different cases:
    • The tumor is smaller than 5 cm (2 inches) and has spread to 4–9 lymph nodes under the arm
    • The tumor is smaller than 5 cm (2 inches) and has spread to detectable lymph nodes under the breast bone
    • The primary tumor is larger than 5 cm (2 inches) and has spread to lymph nodes under the arm
    • The primary tumor is larger than 5 cm (2 inches) and has spread to lymph nodes under the breast bone
  • Stage IIIB - cancer directly involves the chest wall or skin. The cancer may or may not have spread to internal lymph nodes on the same side of the chest.
  • Stage IIIC - in this stage, cancer has spread to one of these places:
    • The lymph nodes above or below the collar bone (clavicle) on the same side
    • A large number (ten or more) of lymph nodes under the arm
    • Lymph nodes under the arm and under the breast bone

Inflammatory Breast Cancer - this is a special class of breast cancer that is relatively rare. Symptoms are a breast that looks suddenly (over days or weeks) inflamed or red. The redness and warmth occur because the cancer cells affect the lymph vessels in the skin. The skin may have ridges or a pitted appearance, like an orange. This type of cancer tends to spread quickly. Breast cancer that has been present for many months that becomes reddened or inflamed is not usually considered inflammatory.

Stage IV – cancer has spread beyond the breast and lymph nodes to other parts of the body, which may include the liver, lungs, bones, or other sites.

Recurrent/Relapsed Cancer – cancer has returned after a period of treatment.