Breast Cancer: Diagnosis
Doctors perform a number of tests to diagnose breast cancer.
- Clinical breast exams: Women should have a clinical breast exam every three years starting at age 20, and every year starting at age 40. These are hands-on exams, performed at an annual physical or gynecology appointment. If a doctor feels something unusual, she or he will likely order further testing. Your doctor should review with you how to examine your own breast.
- Mammogram: This is a radiological test that the medical community considers the "gold standard" for breast cancer screening and early detection. In fact, mammograms can help detect 85-90% of all breast cancers, even before you can feel a lump. The American Cancer Society recommends that women over 40 have mammograms annually. Other respected organizations suggest that women begin annual mammograms at age 50. The majority of breast cancer specialists, however, are still recommending annual mammograms beginning at age 40. Talk with your doctor to decide when you should begin annual mammogram screenings.
- Ultrasound: Not all breast lesions or abnormalities can be picked up on a mammogram. If your doctor feels something unusual or if a radiologist sees something unusual on a mammogram the next step may be an ultrasound image of the particular area. An ultrasound image can provide additional information about the abnormality seen or felt in the breast. It can be helpful in determining if the lesion is solid (benign or malignant tumor) or liquid (a benign cyst).
- Breast MRI: Magnetic Resonance Imaging uses a powerful magnetic field, radio frequency pulses and a computer to produce very detailed pictures of breast tissue. MRI can provide valuable information about many breast conditions that cannot be obtained by mammography or ultrasound. Also, unlike a mammogram, an MRI does not expose you to radiation. MRI is designed to be used for women with dense breasts and a significant family history, or other known high risk factors. It is not a substitute for a mammogram, however. It is highly sensitive but not specific so it can result in identification of abnormalities that upon further investigation are determined to be normal findings.
Sometimes it will be necessary for the doctor to check inside the breast by examining breast tissue or fluid. This is done with slightly more invasive procedures than imaging tests:
- Fluid aspiration: A doctor will use a very fine needle to take a sample of fluid from a lump. The fluid will then be analyzed to help with diagnosis.
- Tissue biopsy: Often done in conjunction with an ultrasound, a surgeon or radiologist will remove a small sample of breast tissue for analysis. Ultimately, a biopsy of a suspicious lesion is required to determine if it is cancer. 90% of biopsies can be performed with a large gauge needle and are referred to as a core biopsy or stereotactic biopsy. Only suspicious areas that are close to the chest wall require an excisional biopsy done in the operating room by a breast surgeon.