Risk Factors For Breast Cancer

While an exact cause for breast cancer is still unknown, research has revealed a number of factors that impact our risk.

Risk Factors for Breast Cancer You Cannot Control.

Although we are unable to modify the risks associated with the uncontrollable factors, it is important to understand how they may impact an individual’s risk for breast cancer.

Sex

SEX ASSIGNED AT BIRTH

The main risk for breast cancer is sex assigned at birth. Women are at the greatest risk of developing breast cancer, with 99% of breast cancer diagnoses occurring in women. And 1 in 8 women will be diagnosed with breast cancer in her lifetime. Men can also get breast cancer, but makeup about 1% of all breast cancer cases [2].

Aging

AGING

As a person ages, their risk of developing breast cancer increases. This is a result of longer overall exposure to estrogenA female sex hormone that is primarily produced by the ovaries. Its primary function is to regulate the menstrual cycle and assist in the production of secondary sex characteristics such as breasts. It may even play a role in the production of cancer cells in the breast tissue.. Although a person’s risk of developing breast cancer increases with age, young women can also be at risk for breast cancer [2].

Family History

FAMILY HISTORY

Anyone can get breast cancer, but if you have a family history of breast cancer that increases your personal risk. That risk increases with the number of family members diagnosed with breast cancer. In addition, your risk increases if you have a first degree relative with a history of breast cancer such as a parent, sibling, or child, especially if they were diagnosed at an age younger than fifty. The overwhelming majority of breast cancer patients have no family history of the disease [3].

Breast Density

BREAST DENSITY

Higher levels of breast density can increase your risk of breast cancer [6]. Dense breast tissue can also make it harder for cancer to be detected on a traditional mammogram. If your mammogram reveals you have very dense breasts, you should speak to your doctor about additional screening that may be needed.

Previous Cancer History

Your History

PREVIOUS BREAST CANCER HISTORY

An individual with a history of breast cancer is not only at risk of recurrenceThe reappearance of the disease after it has been treated. In breast cancer, recurrence following primary breast cancer can be local (in the same place), regional (in surrounding tissue) or metastatic (in some other part of the body)., but they are also at a greater risk of developing a new breast cancer [4]. Also, women with a history of ovarian cancer are at a greater risk of developing breast cancer [5].

Genetic Mutations

Genes

ABNORMAL OR MUTATED GENES

GeneticInherited characteristics. mutations can affect a person’s risk of developing breast cancer, particularly certain common gene mutations on the BRCA1A gene which, when damaged or mutated, can put a person at a greater risk of developing breast and/or ovarian cancer. and BRCA2A gene which, when damaged or mutated, may put a woman at a greater risk of developing breast and/or ovarian cancer. This gene is also thought to raise the risk for breast cancer in men. genes. An individual with a mutation in the BRCA1 may have a 72% risk of developing breast cancer. And an individual with a BCRA2 mutation may have a 69% risk. It is important to know your family history and how it may affect your personal risk [7].

Menstruation Menopause

Menstruation

AGE AT FIRST MENSTRUATION/LATE

Getting your first period very early (younger than 12) or late menopause (older than 55) increases risk because of the overall lifetime exposure to estrogen [8].

Risk Factors for Breast Cancer You Can Control.

An estimated 30 percent of breast cancer cases are preventable through lifestyle changes [1]. Most breast cancers are estrogen-related which is why many of the risk factorsAnything that increases or decreases a person’s chance of developing a disease. we can control involve keeping estrogen levels low. Although exposures that influence risk accumulate throughout a woman’s life, research suggests that early life exposures during breast development may be particularly critical.

Nutrition

NUTRITION

A healthy eating pattern includes a diet rich in fruits and vegetables, whole grains, and healthy fats and low in red meat and overly processed foods. Healthy bodies need fat, but research suggests that eating a diet high in trans and saturated fats increases the risk of breast cancer [9]. Explore more content about how diet and nutrition can impact our breast cancer risk.

Alcohol

ALCOHOL

Studies show that drinking alcohol —even just one drink per day—increases your risk for breast cancer. And it doesn’t matter what alcoholic drink you choose. They all impact your risk of developing breast cancer [12].

Breast Feeding

BREASTFEEDING

Breastfeeding for a year or more reduces a woman’s overall risk of breast cancer. The longer a woman breastfeeds, the lower her risk drops. This seems to be most impactful on the risk of triple-negative breast cancer [15].

Obesity

OBESITY

Fat cells in the body store high levels of estrogen, which increases the threat of breast cancer. Thus, maintaining a normal body weight is a crucial component in decreasing your risk [10].

Smoking

SMOKING

Smoking and vaping exposes the body to carcinogens and accelerates cancer tumorA mass of cells that can be benign or malignant. growth. Studies indicate that people who smoke during their teen years significantly increase their risk for breast cancer compared to people who don’t [13].

Contraceptives

HORMONAL CONTRACEPTIVES

The use of oral contraceptives and hormonal intrauterine devices (IUD), have been shown to slightly increase the risk of breast cancer [16].

Exercise

EXERCISE

30 minutes of moderate physical activity per day can help decrease your body fat percentage and the amount of estrogen in your body. It also strengthens your immune system, which enhances your body’s ability to recognize and eliminate early cancer cells [11].

Pregnancy

LATE PREGNANCY OR NO PREGNANCY

Women who have children earlier in life have a reduced risk of breast cancer, compared to those who have children after age 35 or not at all [14].

HRT

Use of combined HRT increases one’s risk of developing breast cancer and risk associated with HRT use never diminishes. It also increases the risk that breast cancer will be found at a more advanced stage and it may reduce the effectiveness of mammogramsA low dose x-ray picture of the breast that allows a doctor to view glandular tissue and determine the presence of cancer. [17].

Sources

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Kramer I, Schaapveld M, Oldenburg HSA, et al. The influence of adjuvant systemic regimens on contralateral breast cancer risk and receptor subtype. J Natl Cancer Inst. 2019;30:30.
Kuchenbaecker KB, Hopper JL, Barnes DR, et al. Risks of Breast, Ovarian, and Contralateral Breast Cancer for BRCA1 and BRCA2 Mutation Carriers. JAMA. 2017;317(23):2402-2416.
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Schwartz GF, Hughes KS, Lynch HT, et al. Proceedings of the International Consensus Conference on Breast Cancer Risk, Genetics, & Risk Management, April, 2007. Cancer. 2008.
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