Breast cancer is extraordinarily rare in teenagers, so much so that most organizations do not keep statistics for the disease in this age group.

Nevertheless, teens may worry that changes in their breasts during puberty are due to breast cancer. To alleviate these concerns, they should monitor their breasts for changes and talk to their doctor if they want reassurance.

They should also know that breast changes are nothing to fear and are unlikely to mean breast cancer.

Fast facts on breast cancer in teens:

• It is virtually unheard for the condition to occur in this age group.
• The disease cannot be diagnosed or ruled out on symptoms alone.
• Because it is so rare in teens, there are no reliable statistics on survival rates.

How does it occur in young women?

The changes that puberty brings can be scary for any young person. Young women develop breasts for the first time and may be unaccustomed to their look and feel. Some may worry about breast cancer.

Early breast development often begins as a lump under the nipple, which may compound worries a young teen may have about breast cancer. These breast buds may also be sensitive, triggering fears that something is wrong.

Parents and doctors should reassure teenagers about normal breast growth, since developing breasts will be a new experience and can be unnerving.

Though rare, it is possible for a teenager to develop breast cancer. Breast cancer, as with all cancers, occurs when normal cells begin growing and dividing out of control. Over time, this growth can form a tumor that harms healthy tissue and may spread to other areas of the body.

About 12% of women will develop breast cancer during their lifetime. However, the most significant risk factor for breast cancer is being older. Genetic and cellular changes over time can increase the likelihood of unusual cell growth in the breasts. So, younger women face a much lower risk.

Young women who develop breast cancer more often have aggressive, fast-growing tumors. Their cancer may also be negative for hormone receptors that increase the chances of survival.

In addition, younger women may wait longer before seeking treatment, meaning that the prognosis for those with breast cancer is often worse than for older women.

How common is breast cancer in teens?

Even in young adult women, the odds of developing breast cancer are very low. Less than 5% of breast cancers occur in women under 40. At age 30, the risk of developing breast cancer is 0.44%. There are less than 25 cases of breast cancer per year in women in each age group under 30. Among teenagers, the figure is close to zero.

These statistics mean that issues with the breasts are almost certainly due to other causes and these are often just normal development.

Other reasons a teenager might develop a lump in her breast include:

Fibroadenoma: A fibroadenoma is a benign breast tumor. Common among women in their 20s and 30s, these lumps do not turn into cancer. They have clear borders and range in size from very tiny to several inches. They are associated with a slight increase in the risk of breast cancer.

Cystosarcoma phyllodes: Phyllodes are tumors that grow fast, but they are almost always benign. They are very rare, but in 10% of cases, they can spread to other areas of the body. So women with these tumors may elect to have them removed.

Breast cysts: Cysts are small growths in the breast tissue, akin to pimples under the skin. Some women have fibrocystic breasts, which means their breasts contain many cysts and may feel lumpy.

Teens who have fibrocystic breasts should talk to a doctor about their concerns. Knowing how their breasts normally feel can help women with a lumpy breast distinguish cancer from a cyst.

Types of breast cancer

Similarly to older women with breast cancer, teens with breast cancer can experience many different types of the disease. The most common include:

In situ cancers

In situ are easier to treat and less likely to be fatal.

The most common types of in situ cancers are ductal carcinomas and lobular carcinomas. A ductal carcinoma is a noninvasive cancer sometimes called pre-cancer or stage 0 breast cancer. Lobular carcinoma grows in the milk ducts and typically does not spread.

Invasive breast cancers

Invasive breast cancers are forms of cancer that can spread, potentially affecting the lungs, brain, liver, and other vital organs. They are more likely to be fatal, particularly if they are not promptly caught and treated. There are invasive forms of both lobular carcinoma and ductal carcinoma.

Less common cancers

Other breast cancers are far less common. They include:

• inflammatory breast cancer, which may cause swollen or red breasts
• Paget disease of the nipple, which spreads from the breasts to the nipple and areola
• angiosarcomas or cancers that begin in blood or lymph vessels and spread to the breasts
• phyllode tumors that turn cancerous

Symptoms

An annual breast exam and a relationship with a trusted doctor are valuable tools for diagnosing breast-related conditions. Even teens that have several symptoms associated with breast cancer should know that these are likely due to another cause.

Some 90% of breast lumps are not due to cancer. Cancerous lumps tend to be hard, with irregular borders, not soft or movable.

Common breast cancer symptoms include:

• a breast lump or lumps
• swollen lymph nodes under the armpits or in the neck
• unexplained changes in the size, shape, or symmetry of the breasts
• changes in the skin of the breast or nipple
• discharge from the nipple not related to menstruation, pregnancy, or breastfeeding
• a breast that looks red or swollen
• puckering or dimpling of the breast skin
• an itchy, scaly rash on the breast

People with multiple breast cancer risk factors may be more vulnerable. Those risk factors include:

• having a mutation on the genes BRCA1 or BRCA2
• having several relatives who have had breast or ovarian cancer
• not being active or being obese or overweight
• exposure to radiation
• taking estrogen therapy or hormonal birth control pills
• heavy drinking
• smoking

Breast cancer vs normal development

Normal breast development can resemble breast cancer, and it is not possible to tell what is normal and what is not based on a comparison of symptoms.

Normal breast development, however, usually follows a pattern. It begins with nickel-sized lumps under each nipple, and the breasts gradually grow from these lumps.

Surviving teen breast cancer

Breast cancer, in general, is survivable with prompt treatment. This is particularly true of noninvasive breast cancers, and of breast cancers that have not spread to other areas of the body.

Treatments often include chemotherapy, radiation, medication, surgery, or a combination of these.

Checking yourself for breast cancer

Breast self-exams to check for lumps and other changes can help women detect the early signs of cancer.

Even more important than looking for specific changes is knowing how your breasts feel normally. A change in their shape or texture, a new lump, or other significant change could signal a problem, including cancer.

Women should also get regular breast exams from their doctor. Those at high risk of breast cancer may need annual mammograms, although teens almost never fall into this category.

When to see a doctor

Delaying treatment can reduce the chances of survival as it may allow a cancer to spread. Girls concerned about their breasts should see a doctor immediately, even though teen breast cancer is rare.

Takeaway

Thoughts of breast cancer can be scary, especially for girls when their breasts are developing. However, there is little reason for most teenagers to be anxious about breast cancer. Rather than worrying, a better strategy is to adopt a healthy lifestyle that helps to protect against breast cancer in the future.

A doctor can help girls and young women determine their individual risks, and assist their understanding of any unusual breast symptoms.

—Zawn Villines