Breast Cancer: Diagnosis

Breast Imaging technologies allow physicians to detect cancer at an early stage, when patients receive the optimal effects from treatment.

Mammography

For over thirty years, mammography—an x-ray image involving the compression of the breast—has been an important tool for early diagnosis and it is recommended that women over age 40 or 50 have a screening mammograms everyach 1-2 years.

Mammography is recommended for most suspicious breast lumps but a biopsy is often needed to confirm the diagnosis.

The sensitivity of mammography decreases as the density of the breast increases. However, one of its great benefits is to detect microcalcifications—tiny spots of calcium in the breast.  While often benign, these sometimes indicate the presence of ductal carcinoma in situ (DCIS), a very early stage of breast cancer. Microcalcifications are not detected by breast MRI or by ultrasound.

Ultrasound

This approach uses sound waves to take images of the breast. The skin is usually lubricated with gel, then a small, microphone-like instrument called a transducer is placed on the breast.  The transducer emits sound waves and picks up the echoes as they bounce off body tissues. These echoes then appear as a black and white image on a computer screen. This test is painless and does not expose you to radiation.

Breast ultrasound may be a helpful addition to mammography when screening women with dense breast tissue. It is also useful for evaluating some breast masses and to determine if a suspicious area is a cyst (fluid-filled sac). In addition, ultrasound can help doctors guide a biopsy needle into some breast lesions.

Magnetic Resonance Imaging (MRI)

  • For patients at high-risk for breast cancer, the most appropriate screening tool is a breast MRI, using magnetic fields and radio waves to create a detailed image of the breast.   In the “high-risk” category are women who have at least a 20-25 percent chance of developing breast cancer in their lifetime, including those with:
  • Mutations of BRCA1/2 genes or other hereditary breast cancer syndromes
  • Lifetime breast cancer risk >20-25%, based upon family history
  • Previous radiation treatment to the chest, for example for the treatment of lymphoma

In some cases, women with high-risk lesions, atypia, or lobular carcinoma in site are considered candidates for a screening breast MRI.

Biopsy

When a lump is found, a needle biopsy can be performed in the physician’s office. A local anesthetic is injected into the breast, and light suction is applied through a hollow needle inserted into the lump to remove a sample of tissue or fluid. Disappearance of the lump after fluid is withdrawn usually indicates a benign cyst. Nevertheless, the fluid is sent to a laboratory for analysis. If no abnormal cells are found, no further tests are required.

In some cases, a surgical biopsy may be necessary. This procedure entails removing the lump and small amounts of surrounding tissues for laboratory analysis. A surgical biopsy usually is done in a hospital (often as out-patient surgery) using either local or general anesthesia. About 80 percent of these biopsies show no cancerous cells.

Additional Tests

When a tumor is found, it is tested to determine whether it is hormone sensitive (estrogen or progesterone -receptor- positive). Additional tests are sometimes performed to measure the rate at which tumor cells are dividing (Ki67 proliferation marker) and to detect presence of abnormal genes such as one called HER2/Neu.