Causes of Breast Asymmetry and Masses in Teen Girls

As early as 9 or 10 years of age, adolescents begin to experience changes in almost every area of their internal and external selves. Their thinking becomes more concrete and less imaginary, they begin to experiment and test limits, they become introspective and concerned with 'who they really'.

This is also the time period in which teenage girls enter puberty, the sequence of physiologic changes that prepare a girl's body for reproduction. For teenagers attempting to deal with the changes that accompany adolescence, it is common to worry that physical changes occurring with their bodies are not normal. However, the vast majority of teenagers are healthy and experiencing normal changes.

Breast development is an inevitable aspect of puberty for teen girls. However, certain breast changes that occur during this time can be worrisome to a teenage girl. These breast changes are discussed below.

Breast concerns in teenage girls:

Breast asymmetry: Normal teenage girls may find that one breast develops before the other resulting in different sized breasts. It is also normal for girls undergoing puberty to note that both breasts began developing at the same time, but one breast is growing more rapidly than the other. This also results in breast asymmetry.

The physical examination in most teens with different sized breast is often normal, revealing no breast masses or nipple discharge. These girls should be reassured that the difference between breasts becomes significantly less noticeable as their breasts grow and mature.

Breast masses: It is fairly common for teenage girls to note lumps in their breasts. The breast mass is most often a fibroadenoma or a breast cyst. A fibroadenoma is a completely benign mass with no potential to turn into breast cancer. Classic or juvenile fibroadenomas account for 70 percent of breast masses in adolescents.

A cyst in the breast is also a benign condition that is fairly common. In some girls this may be a discrete cyst, whereas in other teenagers the cyst may be the result of fibrocystic changes in the breast tissue. Fibrocystic changes are quite common and are often associated with tenderness and breast swelling. These symptoms are often worst just prior to each menstruation period.

Breast cancer is exceedingly rare in teenagers, with breast carcinomas occurring in less than one percent of all adolescents. Other uncommon causes of breast lumps in teen girls are abscesses, mastitis, intraductal papillomas, fat necrosis, adenomatous hyperplasia, cystosarcoma phylloides (a low-grade cancer), hemangiomas, lymphangiomas, and rarely lymphoma.

If a physician is concerned about the cause of a breast lump in a teenage girl he or she will request ultrasound imaging of the breast tissue. Ultrasound is preferred when imaging young women because the density of adolescent breast tissue will create poor quality radiographic mammogram imaging.

Breast changes are an entirely normal aspect of puberty in teenage girls. Asymmetry of the breasts and breast masses may be concerning to teenage girls. However, these conditions are most often normal processes. A visit to the physician can help provide the reassurance of normalcy that is so important at this time of exciting, often overwhelming, changes in a girl's life.