Breast Cancer

What is Breast Cancer?

Breast cancer forms in the tissues of the breast and can occur in both men and women.

Different types of breast cancer include:

Ductal Carcinoma In Situ (DCIS) is non-invasive and often considered a pre-cancer.

Abnormal cells are present in the breast duct, but have not spread beyond the duct to surrounding tissue. DCIS is typically diagnosed by screening mammograms.

Invasive Ductal Carcinoma is the most common type of breast cancer among women. 

It forms in the tubes that carry milk in the breast. In its earliest form, it is usually diagnosed on screening mammograms, but may also present as a mass you can feel.

Invasive Lobular Carcinoma forms in the glands or lobules of the breast.

Inflammatory Breast Cancer grows in sheets instead of lumps, and resembles a rash.

Its symptoms are noticeable and usually lead a person to seek medical attention. They include:

  • A sudden increase in breast size
  • Continuous itchiness in the skin of the breast
  • Excessive warmth to the breast
  • More hardness or firmness to the breast than usual
  • A change in skin texture becomes similar to the skin of an orange

Breast Cancer Risk Factors

Research is improving our understanding of the causes of breast cancer. While the majority of breast cancer cases develop spontaneously, there are some known risk factors:

Family History and Genetic Susceptibility

  • Approximately 5-10% of all breast cancers are caused by a hereditary genetic mutation.
  • Women with the BRCA1 and BRCA2 gene mutations have an increased risk of developing breast cancer.
  • People with a strong family history may want to learn more about genetic screening. A strong family history is defined as multiple first-degree relatives (sisters, mother, daughters and grandmothers), on either the maternal or paternal side, who have a history of breast cancer and/or ovarian cancer.
  • This is especially important if any member of the family was diagnosed with breast cancer pre-menopausally or any male in the family has been diagnosed with breast cancer.

Personal History of Breast Abnormalities

  • Ductal carcinoma in situ (DCIS) and lobular neoplasia are associated with increased risk.


  • The risk of developing breast cancer increases with age. The majority of breast cancer cases occur in women older than age 60.

Age at First Menstrual Period

  • Women who had their first menstrual period before age 12 have a slightly increased risk of breast cancer.

Breast Density 

  • Women with dense breasts may have an increased risk of developing breast cancer than women with average breast density. Many states now require that the radiologist send a letter to inform the person of their increased risk and this may lead to additional screening with ultrasound or even MRI. This is an area that is currently changing and practices may vary depending on where you live or seek care.


  • Women who have never given birth or who gave birth to their first child after age 30 are at a slightly increased risk of developing breast cancer.


  • White women have a greater risk of developing breast cancer than black women; however, black women diagnosed with breast cancer are more likely to have an aggressive subtype of breast cancer.

Screening for Signs & Symptoms

The classic symptom for breast cancer is a lump found in the breast or armpit.

The following symptoms require a medical exam and evaluation:

  • Swelling or lump (mass) in the breast
  • Swelling in the armpit (lymph nodes)
  • Nipple discharge (spontaneous and from one side only)
  • Pain in the nipple
  • Inverted nipple and/or scaly or pitted skin on nipple
  • Unusual breast pain or discomfort

There are many ways to detect or screen for breast cancer. Regular monitoring is the best way to catch breast cancer early, when it is most treatable.

Breast Self-Exam - A monthly breast self-exam will help you notice changes to your breasts’ texture, size and skin condition. Women who do breast self-exams know how their breasts normally look and feel and are able to see changes sooner. Do not hesitate to talk to a doctor or nurse if you have a question about your breasts.
Clinical Breast Exam - A doctor checks the breasts, underarms and collarbone area for abnormalities. A clinical breast exam is often part of a regular visit to a gynecologist or a primary care doctor.
Screening Mammogram - A mammogram is a breast x-ray that can show a lump or abnormality. Mammograms are recommended for women age 40 and older. A mammogram can show a breast lump or abnormality before it can be felt. Talk to your doctor to find out when to have a mammogram.

Diagnosis & Testing

If you have a symptom or an abnormal mammogram, your doctor may order additional tests, such as:

  • Diagnostic Mammogram - Like screening mammograms, diagnostic mammograms are x-rays of the breast. A diagnostic mammogram is often done after a screening mammogram. The radiologist may use different techniques or views to take more detailed images to learn more about any lumps or abnormalities in the breast.
  • Ultrasound - Sound waves and a computer are used to create a picture of the breast. The picture can show whether a lump is solid or filled with fluid. Cysts (fluid-filled sacs) are not cancerous. Solid masses may be.
  • MRI - Magnetic Resonance Imaging uses magnets and radio waves to produce detailed images of the breast. MRIs are often used to screen high-risk women or to gather more information about a suspicious finding on a mammogram. Because MRI does not expose a woman to radiation, it may be used to evaluate a breast lump during pregnancy.
  • Biopsy - A pathologist looks at a sample of tissue under a microscope to check for cancer cells. If cancer cells are found, the pathologist will study them to learn as much as possible about the cancer in order to determine the best course of treatment. A biopsy can be done several ways:
    • Fine needle aspiration - A thin needle is used to sample a breast lump to determine if there is cancer present.
    • Core Biopsy - Also called needle biopsy, a thick needle is used to remove a sample of breast tissue.
    • Surgical Biopsy - A surgeon makes an incision and removes a sample of tissue from the lump or lump area. This procedure is done in an operating room and requires some form of sedation or anesthesia.

“Take things one step at a time. Try not to be overwhelmed by the tidal wave of technical information coming your way. Finally you know your body best; you have to be your own advocate.”

CSC Cancer Experience Registry Member, breast cancer

The doctor will run several tests on the breast cancer cells to learn what treatments may or may not work, how quickly the cancer may grow and spread and the likelihood that the cancer may return. If your cancer spreads to the bone, please see bone metastases. Doctors will also test breast cancer cells for the following characteristics to help determine the best treatment approach:

  • ER- and PR-positive: If the cancer cells have more hormone receptors—estrogen receptors (ER) or progesterone receptors (PR) – than a normal cell, the breast cancer will be classified as estrogen receptor-positive or progesterone receptor-positive. A treatment to block these hormones or their receptors may be recommended.
  • HER2: Like ER/PR receptors, some cancer cells have too many HER2 receptors. These are called HER2-positive cancers. HER2 receptors tell the cell to grow and divide. Therefore, cancers that are HER2-positive are more likely to grow and spread more rapidly. HER2-positive breast cancers can be more aggressive, but also respond to specific HER-2 targeted drugs.
  • Triple Negative: This cancer tests negative for additional estrogen receptors, progesterone receptors and HER2 receptors and is treated with a combination of surgery, chemotherapy and radiation.

Treatment & Specific Side Effects

One of the many decisions you will make about your cancer treatment is choosing a doctor, a health care team and a cancer center that have the expertise and personal touch to make you feel comfortable and respected. It is critical to trust the people who are treating you and to be able to communicate with them.

You have the right to a second, and even third, opinion at any point in your cancer experience. A second opinion can help confirm your diagnosis, understand your treatment options, provide you with access to clinical trials, and help you choose the right health care team.

The treatment options for breast cancer vary depending on the cancer stage, age of the person being treated and their general health. They include:

  • Surgery
  • Radiation therapy
  • Chemotherapy
  • Hormone therapy
  • Targeted therapy
  • Clinical trials

Learn More About These Treatment Options and Specific Side Effects

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