How We Diagnose Breast Cancer

At the Susan F. Smith Center for Women's Cancers, our breast cancer specialists — who evaluate tens of thousands of people for signs of breast cancer each year – have the experience and expertise to provide the highest quality of care. Affiliated with Harvard Medical School, we have a team of radiologists and pathologists who specialize in diagnosing breast cancer, and defining the specific features of each patient's tumor so that the treatment team can develop the optimal, personalized treatment plan for each patient.

We provide screening and diagnostic services for people who:

  • Need a routine mammogram.
  • Are experiencing breast symptoms, such as a lump.
  • Require follow-up as part of their long-term survivorship care.

Learn more about our approach to caring for patients with breast cancer.

Comprehensive Diagnosis

Our team of radiologists and pathologists ensure that we get a clear understanding of your tumor type and characteristics so that we can develop a targeted treatment plan. Dana-Farber Brigham Cancer Center researchers were among the first to identify the distinct subtypes of breast cancer, each with a specific treatment plan designed to halt the cancer's growth.

Together, radiologists, pathologists, surgeons, medical oncologists, and radiation oncologists determine whether or not additional tests are needed for a definitive diagnosis. This multidisciplinary team develops the best course of treatment based on your tumor, you, and your needs.

Diagnostic Imaging

Your diagnostic tests may include one or more of the following procedures:

  • Mammogram: X-ray images of the breast. At Dana-Farber Brigham Cancer Center, we use digital mammograms, which provide a clear two-dimensional image highlighting unusual structures such as calcifications or masses, which may need further evaluation. Three-dimensional imaging is an FDA-approved advanced technology that takes multiple images, or X-rays of breast tissue to create a 3D picture of the breast. You may also hear it called breast tomosynthesis. Unlike a traditional mammogram, which only takes one single image, breast tomosynthesis takes multiple images. These multiple images of breast tissue slices give doctors a clearer image of breast masses, and makes it easier to detect breast cancer.
  • MRI (magnetic resonance imaging): Imaging that may show abnormal tissue more clearly than a mammogram. MRIs are used in special situations, often for individuals who have a genetic predisposition to breast cancer, and unclear mammograms.
  • Ultrasound: Imaging that can capture the size and structure of a potential tumor. Ultrasound is rarely used for cancer screening because not all cancers are visible on ultrasound. However, in conjunction with mammography, it is a highly useful tool for diagnosis. For example, ultrasound can further characterize an abnormality seen on a mammogram, or help guide the needle during a breast biopsy.

In some cases, more extensive imaging may be necessary to determine whether breast cancer has spread beyond the breast. When this is the case, CT scans and/or bone scans may be used. In select cases, a PET scan may also be necessary.


If a diagnostic imaging test reveals an abnormal finding that cannot be resolved through other imaging techniques, your doctor will likely recommend a biopsy. Biopsy involves the removal of a small sample of tissue through one of several techniques. The choice of technique depends on the location and quality of the tissue to be examined. Radiologists, pathologists, and, in some cases, surgeons, are involved in the biopsy process.

Types of biopsies include:

  • Fine needle aspiration: This nearly painless procedure involves the insertion of a very thin needle into the suspicious area of the breast. The clinician uses the needle to "aspirate" fluid and cells to be examined by a pathologist.
  • Core needle biopsy: When a slightly larger tissue sample is needed for a definitive diagnosis, a clinician will use a hollow needle to withdraw a thin cylinder from the suspicious area. This type of biopsy requires local anesthesia.
  • Image-guided core needle biopsy: In many cases, it may be impossible to locate a suspicious area through touch. In this case, radiologists use ultrasound, stereotactic (mammographic) imaging, or MRI to guide the removal of tissue using a hollow needle. Stereotactic biopsy finds the exact location of a breast lump or suspicious area by using a computer and mammogram images to determine the three-dimensional lesion location within the breast. A sample of tissue is removed with a needle that is guided to the appropriate area using the 3D coordinates. A titanium clip is typically placed at the time of a core needle biopsy to ensure that the area of interest can be identified after biopsy in the event that additional tissue must be removed.
  • Surgical biopsy: In relatively few cases, other imaging and biopsy techniques may not provide enough information to either diagnose or rule out breast cancer. When that happens, radiologists and surgeons work together to remove all or part of a suspicious mass. In some cases, if the lump can't be felt, a wire is inserted to guide your surgeon to the right location. While this type of procedure does require anesthesia, it almost never requires an overnight hospital stay.

Once a biopsy is completed, tissue samples are examined by pathologists who specialize exclusively in breast cancer. Pathologists' findings are critical to determining the best treatment for your cancer, and, at Dana-Farber Brigham Cancer Center, pathologists are key members of your medical team, providing consultation to clinicians and, at times, working side by side with surgeons. Our pathologists not only evaluate tissues in order to characterize your cancer, but they also investigate any unusual or unexpected findings, using microscopes and analysis to observe and test tissue. Learn more about breast biopsies and sentinel lymph node biopsies.

Learn more about the role that pathology plays in personalizing treatment to individual patients.

Characterizing Breast Cancer: Tumor Characteristics and Receptor Status

Researchers at Dana-Farber Brigham Cancer Center and elsewhere have discovered that breast cancers differ not only in their size, location, and behavior, but also in their genetic and hormonal characteristics. Consequently, treatment may vary significantly and will be customized according to your unique needs and preferences.

Tumor Grade

This system classifies cancer cells in terms of how abnormal they look under a microscope. It also is a factor used to determine an individualized treatment plan.

Grade 1 tumors are generally considered the least aggressive. Conversely, the cells of Grade 3 tumors do not look like normal cells of the same type, and tend to grow more rapidly than tumors with a lower grade.

Staging Breast Cancer

Cancer is staged based on tumor size, location, and the degree to which the cancer has spread, either to the lymph nodes and/or to other parts of the body. A review of your breast mammogram and other imaging, physical exams, and additional scans, when appropriate, can help to determine the clinical stage of your cancer.

  • Stage 0 breast cancer is a non-invasive condition which could be described as pre-cancerous. Diagnoses considered to be Stage 0 include ductal carcinoma in situ (DCIS) and lobular carcinoma in situ (LCIS). Neither of these diseases is considered to be life-threatening in this early stage, but can become invasive over time if not appropriately treated, and both increase the risk of developing breast cancer in the future.
  • Stage I cancer usually involves a tumor that is two centimeters or smaller and has not spread outside the breast. Stage I cancers are almost always curable.
  • Stage II and III cancer includes medium- to larger-sized tumors as well as tumors with positive lymph nodes. With advances in breast care treatment, stage II and stage III cancers are often curable, but many require additional treatments to achieve this goal.
  • In Stage IV, the cancer has spread to other organs of the body, most often the bones, lungs, or liver. Another name for Stage IV cancer is metastatic cancer.

Dana-Farber Brigham Cancer Center has extensive resources for treating metastatic breast cancer, including a range of clinical trials.

Tissue Biomarkers

At Dana-Farber Brigham Cancer Center, breast pathologists collaborate closely with other members of your team to evaluate breast tissue and determine your tumor's specific characteristics. While you may never meet your pathologists face-to-face, it is important to know that he or she will consult directly with your clinicians — medical oncologist, surgeon, radiologist, radiation oncologist — and may even be present in the operating room to ensure that tissues removed during a biopsy are sufficient to evaluate the characteristics of your cancer.

The ability to distinguish between different subtypes of breast cancer has led to more refined treatments, allowing doctors to prescribe treatment likely to provide benefit, and reduce the use of therapies that may not be as effective — an important consideration for patients' quality of life. The improvements in drug therapy have been mirrored in radiation therapy and surgery, where doctors can better determine which patients are likely to benefit from which form of treatment, and can then deliver treatment more precisely.

Research Progress

At Dana-Farber Brigham Cancer Center, we continue to advance our understanding of breast cancer genetics and care with the Tissue Resource for Research. Using donated tumor tissue and blood samples from current and former breast cancer patients, specimens from the bank aid in the search for cancer biomarkers — tests of genes, proteins, or other markers that might help predict a patient's prognosis, the effectiveness of treatment, or the chances of side effects from treatment. The benefits, both in terms of improved tumor detection and more rapid development of treatments, are expected to be substantial.

Hormone Receptor Status

Estrogen and progesterone are both hormones. Breast cancer cells that have estrogen receptors are called estrogen receptor (ER) positive, and those with progesterone receptors are called progesterone receptor (PR) positive. If your tumor cells do not have receptors for either hormone, it is called hormone receptor-negative. If your tumor is hormone receptor-positive, your treatment may include specific medications which block hormone signaling or reduce your body's natural estrogen production. Treatment milestones include the development of the ER-inhibiting drug tamoxifen in the 1980s.


The HER2 protein can be present in excess amounts on the surface of the cancer cell. This typically happens when there are too many copies of the HER2 gene in the cell. If your tumor has higher than normal amounts of this protein — also referred to as HER2-positive — your treatment may include drugs targeting HER2, for example Herceptin (trastuzumab), known to be effective against tumors controlled by the HER2 gene.

Dana-Farber Brigham Cancer Center investigators are leading and participating in an array of clinical trials of drugs targeting HER2-positive breast tumors. Dana-Farber Brigham Cancer Center investigators have led and participated in trials of Perjeta (pertuzumab), Kadcyla (TDM1), and Tykerb (lapatinib), all of which are FDA-approved for the treatment of patients with metastatic breast cancer, and are being studied in patients with early-stage disease.

Laboratory research by Dana-Farber Brigham Cancer Center scientists suggests that shutting down a protein called P13 kinase — which may be active in Herceptin-resistant, HER2-positive tumors — can inhibit cancer cells. Our investigators are studying the safety and effectiveness of several P13 kinase blockers in patients.

Triple-Negative Breast Cancer

Approximately 15 percent of breast cancers do not express estrogen receptor, progesterone receptor, or HER2. "Triple-negative" breast cancer may be a more aggressive form of cancer. In patients with early-stage disease, chemotherapy is often recommended for treatment.

There is significant research and interest in how best to treat triple-negative breast cancer. Dana-Farber Brigham Cancer Center researchers have discovered several very promising molecular targets for drug therapy, including the Jak2/Stat3 pathway. When investigators tested compounds that block those genes in the laboratory, tumor growth was inhibited. Researchers have also discovered that certain subtypes of triple-negative breast cancers may be very responsive to a class of chemotherapy called platinum chemotherapy. Clinical trials at Dana-Farber Brigham Cancer Center are currently underway to investigate the activity of platinum chemotherapy and other promising treatments.

Find out more about triple-negative breast cancer.

Second Opinions

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Consultations and Second Opinions

Our diagnostic team provides second opinions, including for challenging or difficult cases. We are happy to consult with primary care physicians or other specialists. Consider a second opinion for:

  • Confirmation of a diagnosis
  • An evaluation of an uncommon presentation
  • Details on the type and stage of cancer
  • Treatment options
  • Clinical trials

Phone: 877-442-3324
Online: Complete the Appointment Request Form

Can't travel to Boston? Our Online Second Opinion service lets patients from all over the world receive expert second opinions from Dana-Farber oncologists.

For Referring Physicians

Because you, the referring physician, are an integral part of your patient's care team, we are committed to collaborating with you to provide the best care for your patient.