Breast Cancer Diagnosis and Stages

Precise technology determines the best treatment

A smiling middle-aged woman represents the empowerment that comes with understanding your breast cancer diagnosis.

Precise technology determines the best treatment

At Scripps Cancer Center, a breast cancer diagnosis may involve several types of tests, starting with a physical exam or screening mammography, to look for breast abnormalities. If something unusual is found, the next step will be diagnostic testing to see whether the abnormal finding is in fact breast cancer. Diagnosing breast cancer also involves determining the type of cancer and its stage, or how far it has spread.

How is breast cancer detected and diagnosed?

How is breast cancer detected and diagnosed?

For many women, the first sign of cancer is a lump or mass in the breast found during a self-exam, a clinical exam or a breast cancer screening mammography. These early detection methods can help find breast cancer at its earliest stages, when treatment is most likely to be successful.


If a breast cancer screening exam finds something unusual, or a physician recommends further testing for other reasons, the next step is usually additional tests to confirm the diagnosis, such as a diagnostic mammogram or ultrasound exam. A biopsy may be performed as well.


Depending on the results, a patient may be referred to an oncologist or other cancer specialist for further diagnosis and staging to determine how far the cancer has spread and the most appropriate cancer treatment plan.

Imaging and diagnostic testing

Imaging and diagnostic testing

Scripps offers the most advanced testing for breast cancer diagnosis.


  • All Scripps locations provide state-of-the-art digital mammography, which uses lower doses of radiation than conventional mammography and produces clearer, high-resolution images of breast tissue to detect potential abnormalities at their earliest stages.
  • All diagnostic mammograms are read by physicians specializing in breast imaging.
  • Every mammogram is double-checked by a computer-aided detection system for ensured accuracy.
  • Scripps mammography centers are accredited by the American College of Radiology.


In addition to mammography, Scripps offers screening MRI, ultrasound and other exams.


Scripps provides breast screenings and mammography services at more than a dozen Scripps Health locations in San Diego County, as well as our three dedicated specialty breast care centers.

Diagnostic mammogram

Diagnostic mammography is an imaging technique that uses X-rays to examine abnormalities in breast tissue. A diagnostic mammogram zeroes in on the suspicious area, taking images from several angles and magnifying them for closer inspection.

Breast-specific gamma imaging (BSGI)

Breast-specific gamma imaging (BSGI) creates high-resolution images of breast tissue using nuclear imaging. During the test, a woman receives an intravenous injection of a radioactive substance called a tracer into her arm. As the tracer moves through the breast tissue, cancer cells absorb more of the tracer than healthy tissue and “light up” on the imaging screen. BSGI, also known as molecular breast imaging (MBI), is used along with mammography.

Magnetic resonance imaging (MRI)

Magnetic resonance imaging (MRI) for breast cancer diagnosis can determine how far breast cancer has spread in the breast and potential lymph node involvement. Breast MRI can also help evaluate how well treatment is working if chemotherapy is given before surgery. Used in combination with mammography or ultrasound, MRI uses powerful magnets and radio waves to create images of the breast tissue.

Breast ultrasound

Diagnostic ultrasound, an imaging procedure that uses sound waves to create pictures of the breast tissue, is often used after mammography to obtain more information. During ultrasound, a wand-like instrument is moved over the breasts and armpit area. The images are then recorded and displayed for review.

Biopsy

Diagnosing breast cancer usually requires a biopsy, or removal of a small sample of breast tissue, which is evaluated by a pathologist who specializes in analyzing the sample under a microscope to determine if it is cancer. Scripps oncology specialists perform several types of biopsy to diagnose breast cancer:


  • Ultrasound-guided breast biopsy — a Scripps radiologist uses ultrasound as a guide to accurately obtain a sample of breast tissue
  • Stereotactic core needle breast biopsy — a Scripps radiologist uses computer-guided mammography imaging to precisely obtain a sample of the breast tissue in question
  • Magnetic resonance imaging (MRI) core needle breast biopsy — a Scripps radiologist uses computer-guided MRI imaging to precisely obtain a sample of the breast tissue in question
  • Fine needle aspiration — a Scripps physician removes tissue or fluid from the suspicious area for testing

Computed tomography (CT) scan

Often used to diagnose inflammatory breast cancer, a CT scan uses X-rays to provide detail about the size, shape and location of any growths in the breast and surrounding areas.

Positron emission tomography (PET) scan

A PET scan may be used to diagnose inflammatory breast cancer. During a PET scan, a radioactive substance called a tracer is given intravenously (IV). Cancer cells may metabolize this substance faster than the surrounding healthy cells. Using advanced imaging technology, the PET scan shows the areas of abnormal metabolism to help pinpoint where a disease is originating in the body and how it’s progressing.

Breast cancer stages

Breast cancer stages

The breast cancer stage defines how far cancer may have spread inside the breast or to other parts of the body. Diagnostic imaging and testing help physicians determine the stage of cancer, as well as how best to plan breast cancer treatment. In some cases, the stage will be determined after the tumor and often a few lymph nodes from the underarm area have been surgically removed. This tissue is evaluated by the pathologists with a microscope. Generally, the lower the stage, the better the breast cancer prognosis.


Breast cancer staging is determined by:


  • The size of the tumor
  • Whether the cancer has spread to the breast tissue, meaning it has broken through the wall of the lobule of milk duct (invasive) or is confined to the lobules that produce breast milk or ducts that carry milk to the nipples (non-invasive)
  • Whether the cancer has spread to the lymph nodes
  • Whether cancer has spread to other parts of the body


Doctors also may describe breast cancer as:


  • Local when the cancer has not spread beyond the breast tissue
  • Regional when the cancer has spread to the lymph nodes in the armpit or nearby
  • Distant when the cancer has spread to other parts of the body


Because inflammatory breast cancer affects the lymph vessels and the skin, all cases start at stage IIIB.

Stage 0 breast cancer

Stage 0 describes non-invasive breast cancers, which means the cancer cells have not spread from the area where they started — usually in the milk ducts or lobules — or into healthy breast tissue. Ductal carcinoma in situ (DCIS) is a stage 0 breast cancer.

Stage I breast cancer

Stage I breast cancer is invasive, which means cancer cells have spread beyond where they started into healthy breast tissue. Stage I is divided into two substages.


Stage IA breast cancer is invasive and:


  • The tumor measures up to 2 centimeters, AND
  • The cancer has not spread outside the breast or to lymph nodes


Stage IB breast cancer is invasive and:


  • There is no tumor in the breast; instead, small groups of cancer cells — larger than 0.2 millimeter but not larger than 2 millimeters — are found in the lymph nodes, OR
  • A tumor in the breast is not larger than 2 centimeters, and there are small groups of cancer cells — larger than 0.2 millimeter but not larger than 2 millimeters — in the lymph nodes

Stage II breast cancer

Stage II is divided into two substages.


Stage IIA is invasive breast cancer in which:


  • No tumor can be found in the breast, but cancer (larger than 2 millimeters) is found in one to three lymph nodes under the arm (called axillary lymph nodes) or in the lymph nodes near the breastbone, OR
  • The tumor measures 2 centimeters or smaller and has spread to the axillary lymph nodes, OR
  • The tumor is larger than 2 centimeters but not larger than 5 centimeters and has not spread to the axillary lymph nodes


Stage IIB is invasive breast cancer in which the tumor is:


  • Larger than 2 centimeters but not larger than 5 centimeters and small groups of breast cancer cells — larger than 0.2 millimeter but not larger than 2 millimeters — are found in the lymph nodes, OR
  • Larger than 2 centimeters but not larger than 5 centimeters and cancer has spread to one to three axillary lymph nodes or to lymph nodes near the breastbone, OR
  • Larger than 5 centimeters but has not spread to the axillary lymph nodes

Stage III breast cancer

Stage III is divided into three substages:


Stage IIIA is invasive breast cancer in which either:


  • No tumor is found in the breast or the tumor may be any size; cancer is found in four to nine axillary lymph nodes or in the lymph nodes near the breastbone, OR
  • The tumor is larger than 5 centimeters; small groups of breast cancer cells (larger than 0.2 millimeter but not larger than 2 millimeters) are found in the lymph nodes, OR
  • The tumor is larger than 5 centimeters; cancer has spread to one to three axillary lymph nodes or to the lymph nodes near the breastbone


Stage IIIB is invasive breast cancer in which:


  • The tumor may be any size and has spread to the chest wall and/or skin of the breast and caused swelling or an ulcer, AND one of the following
  • May have spread to up to nine axillary lymph nodes, OR
  • May have spread to lymph nodes near the breastbone


Stage IIIC is invasive breast cancer in which:


  • The tumor is any size (or can't be found), AND one of the following
  • Cancer has spread to 10 or more axillary lymph nodes, OR
  • Cancer has spread to the lymph nodes under or above the collar bone, OR
  • Cancer has spread to 4 or more axillary lymph nodes and affected internal mammary lymph nodes

Stage IV breast cancer

Stage IV breast cancer has spread from the breast to other parts of the body, such as the liver or other organs, or to distant lymph nodes. This stage may be described as “advanced breast cancer” or “metastatic breast cancer” and may be used to describe a first-time breast cancer or breast cancer that has come back and spread to other areas.

Understanding your diagnosis

Understanding your diagnosis

No one wants to hear that they have breast cancer. You may feel frightened, overwhelmed, anxious or sad. All of these feelings are perfectly normal. The more you learn about your diagnosis and next steps, the sooner you can begin to make informed decisions about your treatment.


Questions and considerations

Here are some questions you may want to ask your doctor or health insurance provider regarding your breast cancer diagnosis:


  • Should I get a second opinion?
  • How do I find a specialist?
  • What is my cancer treatment plan?
  • Will I have to miss work/school?
  • What are the side effects of breast cancer treatment?
  • How successful is my treatment likely to be?
  • What costs will be covered by insurance?
  • Which costs will I be responsible for?


Your Scripps cancer care team will be with you every step of the way, ensuring that your care revolves around your medical, personal and practical needs. From your diagnosis through your breast cancer treatment, your nurse navigator will coordinate your care, answer questions and provide support. In addition, Scripps offers many resources for our breast cancer patients, from education and support groups to integrative programs, such as yoga and meditation. For more information, visit our cancer patient resources section.