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The Anatomy of a Breast

A woman's breasts change constantly during her life, and not all of those changes are visible. By understanding those changes, women are better able to monitor the health of their breasts.


The breast consists of five major sections:


lg_sideview.jpgChest wall
This large group of muscles between the breasts and the rib cage provides support to the breasts.

Lymph nodes

Small clumps of tissue under the arm and beneath the breast (see illustration at right) that drain and filter fluids from breast tissue. Breast cancer can spread to the lymph nodes.

Fibrous tissue
The tissue located under the skin that gives the breasts their firmness. As women age, they have less of this tissue, reducing the firmness of their breasts.

Mammary glands
Consisting of 7 to 12 lobes, these glands create and deliver milk to the nipples through tubes called ducts. After menopause, the glands are replaced by fat tissue.

Fat tissue

The breast's covering. The amount of fat tissue depends upon a woman's weight and age, and increases after menopause.