- Armando E. Giuliano, MD
Breast cancer is a malignant proliferation of epithelial cells lining the ducts or lobules of the breast. In the year 2004, about 216,000 cases of invasive breast cancer and 40,000 deaths occurred in the United States.
Epithelial malignancies of the breast are the most common cause of cancer in women (excluding skin cancer), accounting for about one-third of all cancer in women. As a result of improved treatment and earlier detection, mortality from breast cancer has begun to decrease substantially in the United States. This chapter will not consider rare malignancies of the breast, such as sarcomas and lymphomas, but will focus on the epithelial cancers.
Human breast cancer is a clonal disease; a single transformed cell - the product of a series of somatic (acquired) or germline mutations - is eventually able to express full malignant potential ...
- Ann Partridge and Eric Winer
In 2000, an estimated 182,800 women were diagnosed with breast cancer in the United States. This figure represents approximately 30% of cancer diagnoses in women, with breast cancer ranking as the most frequently diagnosed cancer and the second leading cause of cancer death among women in the United States.
The average American woman has a 12% lifetime risk of a personal breast cancer diagnosis. The longer a woman lives without cancer, the lower her future risk of breast cancer. For example, a 50-year-old woman who has not had breast cancer has an 11% chance of having breast cancer in her lifetime; a 70-year-old woman has a 7% chance of developing breast cancer during the remainder of her life.
However, these risks can increase dramatically ...
Nipple discharge is a common breast symptom and one that can be particularly alarming when first discovered. There are many underlying causes of nipple discharge. The breast specialist’s job is to differentiate the serious underlying causes of nipple discharge from those that do not require any further evaluation.
In order of decreasing frequency, the following are the most common causes of nipple discharge in the nonlactating breast: duct ectasia, intraductal papilloma, and carcinoma. The important characteristics of the discharge and some other factors to be evaluated by history and physical examination are as follows:
Nature of the discharge (serous, bloody, or other).
Association with a mass.
Unilateral or bilateral.
Single or multiple duct discharge.
Discharge is spontaneous (persistent or intermittent) or must be expressed.
Discharge is produced by pressure at a single site or by general pressure on the breast.
Relation to menses.
Premenopausal or postmenopausal.
Patient is taking contraceptive pills or estrogen.
The discharge is usually cloudy and may be green, dark or gray. This type of discharge generally is present with manipulation of the nipple and occasionally can be stimulated by taking a shower.
Generally, a complete breast exam and a close examination of the nipple discharge will be done to determine what may be causing the discharge. A mammogram and an ultrasound, that would evaluate the main milk ducts behind the nipple, may be used.
Identification of risk factors is important in explaining the variation in breast cancer incidence across different populations. Risk factors can also identify women who may benefit from increased surveillance or preventive treatments. Table 33.2 outlines the major established risk factors for breast cancer, which include family history of breast cancer, early age at menarche, late age at birth of first child, nulliparity, late age at menopause, benign breast disease with proliferative changes, radiation exposure, and hormone replacement therapy.
Given the heightened risk of breast cancer with age, all older women should be considered at increased risk.
