Breast Cancer - Inflammatory: Introduction

Approved by the Cancer.Net Editorial Board, 11/2016

ON THIS PAGE: You will find some basic information about this disease and the parts of the body it may affect. This is the first page of Cancer.Net’s Guide to Inflammatory Breast Cancer. To see other pages, use the menu. Think of that menu as a roadmap to this full guide.

About the breast

The breast is made up of different tissue, ranging from very fatty tissue to very dense tissue. Within this tissue is a network of lobes. The lobes are made up of tiny, tube-like structures called lobules that contain milk glands. Tiny ducts connect the glands, lobules, and lobes. These ducts carry the milk from the lobes to the nipple, located in the middle of the areola. The areola is the darker area that surrounds the nipple. Blood and lymph vessels also run throughout the breast. Blood nourishes the cells, and the lymph system drains bodily waste products. The lymph vessels connect to lymph nodes, the tiny, bean-shaped organs that help fight infection.

About inflammatory breast cancer

Cancer begins when healthy cells in the breast change and grow out of control, forming a mass or sheet of cells called a tumor. A tumor can be cancerous or benign. A cancerous tumor is malignant, meaning it can grow and spread to other parts of the body. A benign tumor means the tumor can grow but will not spread. Breast cancer spreads when the cancer grows into other parts of the body or when breast cancer cells move to other parts of the body through the blood vessels and/or lymph vessels. This is called metastasis.

Inflammatory breast cancer is a rare form of breast cancer. The cancer gets its name because the symptoms, which can include redness, tenderness, swelling, and pain in the breast, are similar to the symptoms of a breast infection. However, unlike an infection, inflammatory breast cancer does not improve with antibiotic treatment.

In inflammatory breast cancer, the cancer cells enter and block the lymph vessels within the breast. This blockage can cause a fluid backup and swelling of the breast and overlying skin. It can also cause the breast to look red and inflamed. Because of the pattern and speed of growth of inflammatory breast cancer, as well as a higher risk of spreading than other types of breast cancer, treatment requires a team approach. Treatment often includes a combination of chemotherapy, surgery, radiation therapy, and possibly hormonal or endocrine therapy. These will be explained in the Treatment Options section.

Breast cancer subtypes

Breast cancer is not a single disease, even among the same type of breast cancer. When you are diagnosed with breast cancer, your doctor will recommend doing lab tests on the cancerous tissue. These tests will help your doctor learn more about your cancer and choose the most effective treatment.

Tests can determine if the cancer is:

  • Hormone receptor positive or negative. Breast cancers expressing estrogen receptors (ER) and progesterone receptors (PR) are called hormone receptor positive. These cancers may depend on the hormones estrogen and/or progesterone to grow. Breast cancer that do not have estrogen and progesterone receptors are called hormone receptor negative.

  • HER2 positive or negative. About 20% to 25% of breast cancers depend on the gene called human epidermal growth factor receptor 2 (HER2) to grow. These cancers are called HER2 positive and have excessive numbers of HER2 receptors or copies of the HER2 gene. The HER2 gene makes a protein that is found on the cancer cell and is important for tumor cell growth. Breast cancers that do not have excessive numbers of HER2 receptors or copies of the HER2 gene are called HER2 negative.

  • Triple negative. If a person’s tumor does not express ER, PR, and/or HER2, the tumor is called triple-negative. This type of breast cancer may grow more quickly than hormone receptor-positive disease, and may be more sensitive to chemotherapy. Inflammatory breast cancers are often triple negative. 

Looking for More of an Introduction?

If you would like more of an introduction to breast cancer, explore these related items. Please note these links will take you to other sections on Cancer.Net:

  • ASCO Answers Fact Sheet: Read a 1-page fact sheet that offers an introduction to breast cancer. This fact sheet is available as a PDF, so it is easy to print out.

  • ASCO Answers Guide: Get this free 52-page booklet that helps you better understand this disease and treatment options. The booklet is available as a PDF, so it is easy to print out.

  • Cancer.Net Patient Education Video: View a short video led by an ASCO expert in breast cancer that provides basic information and areas of research.

The next section in this guide is Statistics. It helps explain how many people are diagnosed with this disease and general survival rates. Or, use the menu to choose another section to continue reading this guide.