Breast cancer can strike at any age, although as the Cleveland Clinic points out, only 5 percent of breast cancer cases occur in women under the age of 40. The Clinic adds that diagnosis is an additional problem, as younger women tend to ignore the signs, believing they are too young to develop this disease. Certain risk factors exist for this age group, and understanding them may benefit younger women in the long run.
BRCA1 and BRCA 2 Genes
The BRCA 1 and BRCA 2 genes are defective genes that pass through generations of paternal or maternal family members. While a number of defective genes may increase the risk of developing breast cancer, these two genes increase the risk the most. The Cleveland Clinic states that most young women who receive a diagnosis are more likely to have either one of the defective genes, which are aggressive and difficult to treat. In many cases, a woman whose breast cancer stems from these genes develops cancer in both of her breasts.
Prior Radiation to the Chest
The American Cancer Society explains that a young woman who received chest radiation either as a child or as a young adult for another cancer treatment faces a significantly higher risk of developing breast cancer; the risk is the greatest if the prior radiation was during adolescence when the breasts were still developing. Chemotherapy given in conjunction with the radiation may lower this risk. This is because chemotherapy may temporarily halt the production of the hormone estrogen by the ovaries.
Family History
Younger women with a family history of breast cancer, especially if their mother, daughter or sister--a first-degree relative--has it, face a greater risk of developing the disease themselves, according to the American Cancer Society. The risk doubles if only one first-degree relative has it, but is five times greater when two first-degree relatives are diagnosed.
Personal History
As the Cleveland Clinic warns, younger women with a personal history of breast cancer have a greater risk of developing breast cancer in the other breast, or in another spot of the original breast the cancer was first found in.
Dense Breast Tissue
Breast tissue is comprised of two types--fatty and dense. As the Cleveland Clinic explains, dense tissue is more common in women under 40 than in older women. Mammograms can detect abnormalities more easily in fatty tissue than in dense tissue, making diagnosis in younger women difficult and increasing the risk factor for developing this disease.
