Each breast has six to nine overlapping sections, called lobes. Within each lobe are many smaller lobules, which end in dozens of tiny bulbs that can produce milk. The lobes, lobules and bulbs are all linked by thin tubes called ducts. These ducts lead to the nipple in the center of a dark area of skin called the areola.
Fat fills the spaces around the lobules and ducts. There are no muscles in the breast, but muscles lie under each breast and cover the ribs.
Each breast also contains blood vessels and vessels that carry colorless fluid called lymph. The lymph vessels lead to small bean-shaped structures called lymph nodes. Clusters of lymph nodes are found in the axilla (under the arm), above the collarbone and in the chest. Lymph nodes are also found in many other parts of the body.
The material in the above section is taken in its entirety from the National Cancer Institute Booklet (No. 95-1556) entitled, "What you need to know about Breast Cancer." Illustrations drawn and contributed by Susan Sprangler.
Basic Facts About Breast Health:
UCSF Health medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.
Breast Cancer Glossary
Check out our comprehensive Glossary of Breast Cancer terminology, which includes definitions of everything from AC chemotherapy to peripheral neuropathy.
Breast Cancer Risk Factors
Click now to find a summary of the factors that increase risk for developing breast cancer, including both factors that we cannot change and those we can.
Self-Care and Recovery
Self-Care and recovery resources including an Introduction to Lifestyle Change, Nutrition and Breast Cancer, Hydration: Water and Health, Meditation and more.
Breast reconstruction, surgery to rebuild a breast's shape, is often an option after mastectomy and is covered by some health insurance plans. Learn more now.
Follow-Up Care for Breast Cancer Patients
After patients have completed treatment for early stage breast cancer, one of the common questions is, "How should I best be monitored?" Learn more here.
Mastectomy: Instructions Before Surgery
The following information will help you prepare for your upcoming Mastectomy surgery. If you have any questions, please contact the Breast Care Center staff.
Mastectomy: Instructions After Surgery
Post Mastectomy surgery instructions including, pain management, incision and dressing care, activity, diet, follow-up care and more.
Menopause and Breast Cancer
Breast cancer treatment often causes women to enter menopause prematurely. Although each woman reacts to therapy individually, certain side effects are common.
Navigating Your Path to Breast Care
Different services and information are needed at different points in breast health care and breast cancer treatment. Learn more here.
Osteoporosis and Breast Cancer
Women who have had breast cancer or are considered at high risk for developing breast cancer are at risk for developing osteoporosis. Learn more.
Breast Care Center in Marin
1100 S. Eliseo Dr., Suite 1
Greenbrae, CA 94904
Carol Franc Buck Breast Care Center
Bakar Precision Cancer Medicine Building
1825 Fourth St., Third Floor
San Francisco, CA 94158