Breast cancer: Nursing pathophysiology

Breast cancer is the uncontrolled growth of abnormal cells in the breast tissue that can spread to other parts of the body.

Okay, so, breasts, also called mammary glands, are milk-producing glands that sit on the chest wall on top of the ribs and the pectoral muscles, made up of glandular, adipose, and connective tissue.

The glandular tissue makes the milk during lactation and is made up of 15 to 20 lobes that surround the nipple in a radial pattern, and each lobe contains many smaller lobules. Inside each of these lobes are grape-like structures called the alveoli containing secretory epithelial cells that produce milk during lactation and myoepithelial cells that contract to move milk from the alveoli.

The alveoli, lobules, and lobes are connected through a network of ducts called the lactiferous ducts that drain the milk produced during lactation.

Surrounding the glandular tissue is the stroma, which contains fibrous connective tissue and adipose tissue, which makes up the majority of the breast.

Lastly, located throughout the breasts are blood vessels, as well as lymphatic vessels that drain into the lymph nodes.

For examination purposes, the breasts are divided into quadrants which include the upper outer quadrant, upper inner quadrant, lower outer quadrant, and lower inner quadrant.

Now, breast cancer is caused by mutations to DNA within breast tissue that results in uncontrolled cellular proliferation.

There are modifiable and non-modifiable risk factors that increase the risk of breast cancer. Modifiable risk factors include exposure to ionizing radiation that can come from medical diagnostics and treatments; postmenopausal hormone replacement therapy; alcohol consumption; exposure to certain environmental chemicals like polychlorinated biphenyls, or PCBs; obesity; and physical inactivity.

Non-modifiable risk factors include age over 65; early menarche or late menopause; being biologically female, though biological males can also develop breast cancer; a family history of breast cancer; and inherited mutations to certain genes, such as BRCA1 and BRCA2.