Anatomy of breasts
Breasts are the subject of a great attention in some societies and generate little in others. Breasts appear in women as other secondary sex characteristics appear. As a woman matures to adulthood the breasts enlarge, with the greatest increase in glandular tissue occurring during pregnancy and after child-bearing. The breasts are composed of glandular and fibrous support tissue surrounded by varying amounts of fat. The amount of glandular tissue increases during the teenage years and decreases after menopause. The glandular tissue is composed of 15-25 lobules which are connected by a series of draining ducts to the nipple. The ducts are somewhat larger just behind the nipple where they form lactiferous ampulla which accumulate breast milk during and just prior to breast feeding. Behind the glandular tissue lies the pectoralis muscles and the ribcage.The size of the breasts is mostly determined by the amount of fat and glandular tissue with the petoralis muscle providing little contribution to size. The breasts generally extend from the level of the anterior second rib to the anterior sixth rib, and laterally extend toward the axilla armpit. Near the armpit there are several small lymph nodes through which lymphatic fluid drains from the breast tissue. Connective tissue strands called suspensory ligaments of Cooper provide support for the breast tissue. The suspensory ligaments in young women are taut and provide a strong supportive structure for the breast tissue. As a woman ages or during pregnancy the suspensory ligaments stretch and become less supportive.
The duct structure of the female breast is arranged in a radial fashion and are directed from the peripheral breast tissue toward the center and anterior aspect of the breast . The nipple and areola can be of variable size and shape. Both of these structures often have a darker skin color than the rest of the breast. The nipple contains a number of smooth muscle fibers which may cause the nipple to change shape and firmness. The nipple may become more prmoninent during breast feeding , exposure to cold or sexual stimulation. The areola contains softer and darker skin tissue which surrounds the nipple and which also contains smooth muscle fibers. The surface of the areola includes many bumps known as glands of Montgomery which provide lubrication during breast feeding. The nipple and areola contain many nerve endings and are often very sensitive to touch.
Female breasts are subject to a variety of problems. Fortunately most problems are not serious and can be evaluated by a women’s family Physician or Gynecologist. Breast self examination is a habit which should be learned early and will allow a woman to become comfortable with how her breast feel. The size, consistency and tenderness can vary during the menstrual cycle. Breast cancer is extremely uncommon in women in their teens and twenties but any new or enlarging lump should warrant a visit to her Physician for a more complete examination.
Cysts are fluid collections which occur in the breasts. Cysts may feel firm as the fluid may be tightly contained within the cyst capsule. Cysts may increase in size and discomfort during the later phases of the menstrual cycle. A cyst can be diagnosed by a breast ultrasound. A simple breast cyst is benign. Occasionally a cyst may not be simple (may contain debris or a solid nodule). When cysts are not simple on ultrasound your doctor may wish to have a radiologist or surgeon aspirate the cyst. The fluid can then be sent to determine if the cyst contains cancerous cells or infection. It has been said that drinking coffee and tea may increase the occurrence of breast cysts. Simple breasts cysts do not indicate cancer, although the presence of cysts may make it harder to detect cancer by palpation or by mammography.
A fibroadenoma is a rounded or spherical nodule containing fibroconnective tissue stroma. The sizes often vary from several millimeters to several centimeters. A fibroadenoma is almost always benign. If a smooth rounded nodule does not change in appearance on mammography or ultrasound for a period of 2 years it is considered unlikely to represent cancer.
These benign tumors are usually located near the nipple area. They contain fibrovascular stroma and often block the ducts in the breast. This may cause bloody discharge from the nipple. Cancer may also cause discharge. The papilloma may be seen on an ultrasound, mammogram, or ductogram.
Breast cancer is a malignant growth which begins in the breast. The growth can invade local tissues of the breast and chest wall as well as spread through the blood and lymphatic systems. When a tumor spreads beyond its site of origin it is said to have metastasized. Breast cancer almost always starts in the glandular tissue of the breast. Although breast cancer can be identified on a mammogram, ultrasound examination at a doctors office, many breast cancers are discovered by the patient as a palpable lump. Most breast cancers begin as a growth arising from abnormal glandular tissue which then grows along the ducts. As the cancer progresses it becomes more invasive and eventually will metastasize. Some types of breast cancer do not arise from or follow the ducts. Breast cancer is more common in some families and ethnic groups. A woman who’s mother or sister has had breast cancer has an increased risk of developing breast cancer herself. About 10% of all women with breast cancer have a family history of the disease. Genetic markers for increased breast cancer risk have been discovered. About 175,000 new cases of breast cancer are discovered in the USA each year. The lifetime risk of a woman getting breast cancer is about one in eight. Age is a very strong risk factor for breast cancer, with 80% occurring in women over 50 years old. Only 1.5% of breast cancers occur in women under 30 years old. Although breast cancer may present as a hard lump, some can not be felt and are only seen on a mammogram. Asymmetries of the breast also raise the suspicion for cancer, although in teenagers some breast asymmetry is most often normal. Nipple inversion, pain, skin thickening, or breast discharge may be signs of cancer and warrant a trip to your doctor.