Advertisement

What are some less common types of breast cancer?

There are several relatively uncommon types of breast cancer. They include the following:
  • Triple-negative breast cancer. Usually invasive (infiltrating) ductal carcinomas (IDCs) whose cells lack certain receptors and tend to grow and spread more quickly than other types of breast cancer. Breast cancers with these characteristics tend to occur more often in younger women and in African American women.
  • Mixed tumors. Contain a variety of cell types, such as invasive ductal cancer combined with invasive lobular breast cancer.
  • Medullary carcinoma. This infiltrating breast cancer has a rather well-defined boundary between tumor tissue and normal tissue.
  • Metaplastic carcinoma. Also known as carcinoma with metaplasia, it is a very rare type of invasive ductal cancer that includes cells that are normally not found in the breast, such as cells that look like skin cells or cells that make bone.
  • Mucinous carcinoma. Also known as colloid carcinoma, this rare type of invasive breast cancer is formed by mucus-producing cancer cells.
  • Paget disease. This breast cancer starts in the breast ducts and spreads to the skin of the nipple and then to the areola, the dark circle around the nipple. Paget disease is almost always associated with either ductal carcinoma in situ (DCIS) or IDC.
Less common types of breast cancer include:

Inflammatory breast cancer: This uncommon type of invasive breast cancer accounts for about 1% to 3% of all breast cancers. Usually there is no single lump or tumor. Instead, inflammatory breast cancer (IBC) makes the skin of the breast look red and feel warm. It also gives the breast skin a thick, pitted appearance that looks a lot like an orange peel. Doctors now know that these changes are not caused by inflammation or infection, but by cancer cells blocking lymph vessels in the skin. The affected breast may become larger or firmer, tender, or itchy. In its early stages, inflammatory breast cancer is often mistaken for an infection in the breast (called mastitis). Often this cancer is first treated as an infection with antibiotics. If the symptoms are caused by cancer, they will not improve, and the skin may be biopsied to look for cancer cells. Because there is no actual lump, it may not show up on a mammogram, which may make it even harder to find it early. This type of breast cancer tends to have a higher chance of spreading and a worse outlook than typical invasive ductal or lobular cancer. For more details about this condition, see the American Cancer Society document, Inflammatory Breast Cancer.

Triple-negative breast cancer: This term is used to describe breast cancers (usually invasive ductal carcinomas) whose cells lack estrogen receptors and progesterone receptors, and do not have an excess of the HER2 protein on their surfaces. Breast cancers with these characteristics tend to occur more often in younger women and in African-American women. Triple-negative breast cancers tend to grow and spread more quickly than most other types of breast cancer. Because the tumor cells lack these certain receptors, neither hormone therapy nor drugs that target HER2 are effective against these cancers (although chemotherapy can still be useful if needed).

Mixed tumors: Mixed tumors contain a variety of cell types, such as invasive ductal cancer combined with invasive lobular breast cancer. In this situation, the tumor is treated as if it were an invasive ductal cancer.
 
Dede Bonner
Health Education
Less common types of breast cancer include the rare but aggressive inflammatory breast cancer; medullary carcinoma (invasive); mucinous (colloid) carcinoma (invasive but good prognosis); Paget’s Disease of the breast (affects the nipple, prognosis very good); tubular carcinoma, (invasive but favorable prognosis); phylloides tumor (tumor in connective tissue); metaplastic carcinoma (localized); sarcoma (affects connective tissue); micropapillary carcinoma (invasive and aggressive); and adenoid cystic carcinoma (invasive but slow growing). Consult a reputable source, such as the National Cancer Institute or the American Cancer Society, to learn more about your kind of breast cancer, especially if you have a rare type.
The 10 Best Questions for Surviving Breast Cancer: The Script You Need to Take Control of Your Health

More About this Book

The 10 Best Questions for Surviving Breast Cancer: The Script You Need to Take Control of Your Health

A good mind knows the right answers...but a great mind knows the right questions. And never are the Best Questions more important than after a diagnosis of breast cancer. Drawing on cutting-edge...

Continue Learning about Breast Cancer

Ask the Experts: Metastatic Breast Cancer Prevention
Ask the Experts: Metastatic Breast Cancer Prevention
Having had breast cancer previously puts you at risk for metastatic breast cancer. In this video, Darria Long Gillespie, MD, explains some of the ways...
Read More
How is the lymph system involved in breast cancer?
Dr. Vincent T DeVita JrDr. Vincent T DeVita Jr
The lymph system is important to understand because it is one of the ways in which breast cancers ca...
More Answers
4 Habits to Keep Your Breasts Healthy
4 Habits to Keep Your Breasts Healthy4 Habits to Keep Your Breasts Healthy4 Habits to Keep Your Breasts Healthy4 Habits to Keep Your Breasts Healthy
Simple things like regular exercise can protect your breasts.
Start Slideshow
How Is Metastatic Breast Cancer Treated?
How Is Metastatic Breast Cancer Treated?

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.