Breast

• The breasts are paired mammary glands that lie over the muscles of the anterior chest wall, anterior to the pectoralis major and serratus anterior muscles.
• Depending on their size and shape, the breasts extend vertically from the second to the sixth rib and horizontally from the sternum to the mid-axillary line.
• The male and female breasts are similar until puberty, when female breast tissue enlarges in response to the hormones estrogen and progesterone, which are released from the ovaries.
• The upper outer quadrant, which extends into the axillary area, is referred to as the axillary tail of Spence. Most breast tumors occur in this

  quadrant
• Lymph nodes are present in both male and female breasts. These structures drain lymph from the breasts to filter out microorganisms and return water and protein to the blood.
• The nipple, which is located in the center of the breast, contains

  the tiny openings of the lactiferous ducts through which milk passes.
• The areola surrounds the nipple (generally 1- to 2-cm radius) and contains elevated sebaceous glands (Montgomery glands) that secrete a protective lipid substance during lactation.
• Hair follicles commonly appear around the

  areola.
• Smooth muscle fibers in the areola cause the nipple to become more

  erectile during stimulation.
• Their color ranges from dark pink to dark brown, depending on the

  person’s skin color.
• The amount of pigmentation increases with pregnancy, then

  decreases after lactation. It does not, however, entirely return to its

  original coloration.
• Female breasts consist of three types of tissue:

  glandular, fibrous, fatty (adipose)
• Glandular tissue - constitutes the functional part of the breast, allowing

  for milk production.
• Glandular tissue is arranged in 15 to 20 lobes that

  radiate in a circular fashion from the nipple.
• Each lobe contains several

  lobules in which the secreting alveoli (acini cells) are embedded in

  grape-like clusters.
• Mammary ducts - from the alveoli converge into a single lactiferous

  duct that leaves each lobe and conveys milk to the nipple.
• The slight enlargement in each duct before it reaches the nipple is called the lactiferous sinus.
• Fatty tissue - This subcutaneous and retromammary fat provides most

  of the substance to the breast, determining the size and shape of the

  breasts.
• The major axillary lymph nodes consist of the anterior (pectoral), posterior (subscapular), lateral (brachial), and central (midaxillary) nodes
• 4 ways of palpating breasts - Wedge, Circular, Vertical strip, Bimanual palpation
• Mammogram - is the screening of choice for breast cancer.
• CANCEROUS TUMORS - These are irregular, firm, hard, not defined

  masses that may be fixed or mobile. They are not usually tender

  and usually occur after age 50.
• FIBROADENOMAS - These lesions are lobular, ovoid, or round. They are firm, well defined, seldom tender, and usually

  singular and mobile. They occur more commonly between puberty and

  menopause.
• BENIGN BREAST DISEASE - Also called fibrocystic

  breast disease. It is marked by

  round, elastic, defined, tender, and mobile cysts.

  The condition is most common from age 30 to

  menopause, after which it decreases.