Breast Anatomy

As you learn about breast cancer, we will repeatedly reference the anatomy of the breast. Understanding the different parts and functions will help you better grasp the details of breast cancer.

Knowing your body helps you to:

  • Make informed decisions.
  • Have a better dialogue with your doctor.
  • Be aware of anything unusual.

Adipose Tissue

The female breast is mostly made up of a collection of fat cells called adipose tissue. This tissue extends from the collarbone down to the underarm and across to the middle of the ribcage.

Lobes, Lobules, And Milk Ducts

A healthy female breast is made up of 12–20 sections called lobes. Each of these lobes is made up of many smaller lobules, the gland that produces milk in nursing women. Both the lobes and lobules are connected by milk ducts, which act as stems or tubes to carry the milk to the nipple. These breast structures are generally where the cancer begins to form.

Lobes, Lobules, And Milk Ducts

A healthy female breast is made up of 12–20 sections called lobes. Each of these lobes is made up of many smaller lobules, the gland that produces milk in nursing women. Both the lobes and lobules are connected by milk ducts, which act as stems or tubes to carry the milk to the nipple. These breast structures are generally where the cancer begins to form.

 

Fibrous connective tissue
This is a supportive tissue between the glands & ducts. Benign breast lesions commonly arise from this tissue like fibroadenoma.

 

Pectoralis muscles

Two muscles called the pectoralis major & pectoralis minor are located
underneath the breast on the chest wall. Occasionally, an advanced breast cancer invades part of the pectoralis muscle and may requires excision of that part during breast surgery.

 

 

 

 

 

Lymph nodes
small bean – shaped glands that drain the breast & help fight infection.
They are located in the axilla (armpit), above the collar bone, in the neck, and inside the chest.

The spread of breast cancer through the lymphatic channels to these lymph node is called
“regional metastasis”. This may require one or more of the following treatments: surgical excision, radiation therapy, and chemotherapy.