During your regular physical exam, your doctor will take a careful personal and family history and perform a breast exam and possibly order a mammogram or an ultrasound of the breasts. In certain women who are at increased risk for breast cancer, an MRI may be ordered.
Based on the results of these tests, your doctor may or may not request a biopsy to get a sample of the breast mass cells or tissue.
After the sample is removed, it is sent to a lab for testing. A pathologist — a doctor who specializes in diagnosing abnormal tissue changes — views the sample under a microscope and looks for abnormal cell shapes or growth patterns. When cancer is present, the pathologist can tell what kind of cancer it is (ductal or lobular carcinoma) and whether it has spread beyond the ducts or lobules (invasive).
Lab tests such as hormone receptor tests (estrogen and progesterone) can show whether these hormones help the cancer to grow. If the test results show that these hormones help the cancer grow (a positive test), the cancer is likely to respond to hormonal treatment. This therapy deprives the cancer of the estrogen hormone.
Breast cancer diagnosis and treatment are best accomplished by a team of experts working together with the patient. Each patient needs to evaluate the advantages and limitations of each type of treatment, and work with her team of doctors to develop the best approach.