Fibrocystic Breast Disease
As stated earlier, because breast tissue is naturally a glandular type of tissue, almost all women develop nodules or lumps in their breasts at some time or another. Lumps, also called "dominant lumps," feel different from surrounding tissue (AMA 1989). Some may be quite large, while others are small and even diffuse over time (Lark 1996). Fibrous tissue in the breast may even be mistaken for a lump. Breast nodules or lumps are the result of several medical causes, including cysts, fibroadenomas, areolar gland abscesses, breast abscesses, intraductal papillomas, mammary duct ectasia, mastitis, Paget's disease, and cancer (Anon. 2000).
Cysts are the most common cause of nodules or breast lumps. Cysts are usually smooth, round, fluid-filled, and slightly elastic. Although the fluid that comes from a cyst is often discolored, the color of the fluid is of little cause for concern unless it is bloody. Cysts occur as an isolated lump, in clusters, or widespread with well-defined lumps of various sizes. Cystic lumps are mobile and do not attach themselves to underlying breast tissue; therefore, cysts do not produce tissue deviation or dimpling. Mobility is one major characteristic that differentiates cysts from malignant nodules. However, cysts are sometimes accompanied by thickened adjacent tissue that is palpable and not so mobile. Breast cysts may also produce a discharge from the nipple that varies from clear and watery to sticky (AMA 1989).
Cysts frequently occur in the upper outer quadrant and the underside of the breast. Symptoms range from a feeling of fullness or heaviness to a dull ache, extreme sensitivity, or a burning sensation. For some women, these symptoms may be severe, making exercising or sleeping on their stomachs painful.
Cysts also often increase in size and tenderness in response to the monthly menstrual cycle because breast tissue undergoes changes related to the normal rise and fall of hormone levels (Lark 1996). After menstruation, the changes and symptoms sometimes abate. Physicians recommend that the best time for breast examination is about 7-10 days after the start of menstruation when breast tissue is more likely to be at its most normal state. Sometimes, after menopause, FBD symptoms completely disappear or become less noticeable (without HRT) (Imaginis 2000).
The occurrence of multiple cysts in one or both breasts is also common in FBD (also called fibroadenosis or chronic cystic mastitis) (Anon. 2000). If a mass is determined to be a cyst, the next step is to determine if it is a simple cyst (one compartment) or a complex cyst (more than one compartment within the cyst). Simple cysts are very unlikely to be malignant.
Sclerosing adenosis is a benign condition with excessive tissue growth in the lobules of the breast (National Cancer Institute 2001b). The condition frequently causes breast pain. Sclerosing adenosis may produce lumps and appears on a mammogram as a calcification (a small deposit of calcium) in breast tissue.
Small, wart-like, benign growths that project into the breast ducts near the nipple are intraductal papillomas (National Cancer Institute 2001b). They usually occur singly, but can also appear as multiple lesions. The smaller nodules are difficult to palpate. The primary sign of intraductal papilloma is nipple discharge, either clear or bloody. Breast pain and tenderness may occur.
Nodules with Potential for Cancer
Complex cysts have more than one compartment within the cyst. Ultrasonography is valuable in differentiating simple cysts from complex cysts or solid masses (Bassett 1991). Complex cysts are somewhat more likely to be cancerous, so doctors will often order further tests, beginning with fine needle aspiration and perhaps a biopsy, to be certain the cyst is not cancerous or pre-cancerous.
Fibroadenomas (sometimes called adenofibromas) are smooth, firm, benign tumors that are extremely mobile, feel slippery, and move around easily in the breast. They consist of structural (fibro) and glandular (adenoma) tissue (Anon. 2000, National Cancer Institute 2001b). Fibroadenomas feel round with well-defined margins and vary from pinhead in size to very large. They grow rapidly and usually occur near the nipple or on the outside of the upper quadrant. Fibroadenomas occur most often in women in their 20s and 30s and occur twice as often in African-American women as in other American women (National Cancer Institute 2001b). When aspirated, if there is no fluid in the lump, it is most likely a fibroadenoma. Fibroadenomas do not cause pain or tenderness. A "complex" fibroadenoma contains abnormal growths or exhibits abnormal cell changes. Although fibroadenomas themselves do not become cancerous (National Cancer Institute 2001b), they can act as markers for the disease. Women with a family history of breast cancer who also develop complex fibroadenomas might be at a higher risk for developing cancer than other women. Fibroadenomas are not difficult to remove and rarely recur.
Paget's disease is a slow-growing intraductal carcinoma that begins as a scaling, eczema-like lesion on the nipple (Anon. 2000). The nipple becomes red and irritated and the lesion extends along the skin and into the ducts. The lesion can progress to a mass located deep in the breast.
Phyllodes tumor is a breast tumor that might be malignant (Mazy 1999). Phyllodes tumor is a rare type of breast tumor, similar to a fibroadenoma, but is composed of an overgrowth of fibrous connective breast tissue that can become quite large. Although rare, if malignancy is discovered via biopsy, the tumor and a margin of normal breast tissue are removed surgically.