Results of a new study, published today in the Journal of the American Medical Association, indicates that although breast cancer is relatively uncommon in women under the age of 40, cases of advanced breast cancer seem to be rising within this age group. Approximately one in 8 women will develop breast cancer during their lifetime, but before the age of 40, only 1 in 173 will have a breast cancer diagnosis.
Researchers analyzed data from a United States government database which contained information on cancer cases from 1976 through 2009. The study found that breast cancer which had spread to other parts of the body had increased from between 1 to 2 cases per 100,000 to 3 cases per 100,000, in women aged 25 to 39.
Lead study author Dr. Rebecca Johnson, medical director of a teen and young adult cancer program at Seattle's Children's Hospital, said, "It's likely that the increase has more than one cause. The change might be due to some sort of modifiable risk factor, like a lifestyle change or exposure to some sort of cancer-linked substance." According to Johnson, the results are equivalent to approximately 250 advanced cases diagnosed in women under 40 during the mid-1970s, versus more than 800 cases in 2009.
Breast cancer has been linked to obesity, alcohol consumption, the use of tobacco and environmental exposures, along with other risk factors for developing the disease. Some experts felt that later pregnancy could be a cause, as an undiagnosed tumor could begin to spread more quickly due to the body's responses to pregnancy hormones.
Dr. Len Lichtenfeld, deputy chief medical officer at the American Cancer Society said that the results, "support anecdotal reports but that there's no reason to start screening all younger women since breast cancer is still so uncommon for them. The study is solid and interesting and certainly does raise questions as to why this is being observed. One of the most likely reasons is probably related to changes in childbearing practices." He added that the trend "is clearly something to be followed."
Routine breast cancer screening using mammography is recommended for women over the age of 40. There has been a great deal of controversy with regard to the necessity of this type of routine screening for younger women. Partner with your healthcare professional to decide what screenings are appropriate for your own specific wellness.