Mammogram in Women Under 40
A new report finds that mammograms in women under 40 are not as beneficial as previously believed. After reviewing records from nearly 200,000 women under the age of 40 who had mammograms performed, radiologist Bonnie Yankaskas of the University of North Carolina at Chapel Hill and colleagues concluded that mammograms did more harm than good.
To determine how effective mammograms were at detecting cancer in women under 40, the team of researchers pooled data from six mammography databases for women who underwent their first mammogram between the ages of 18 and 39. They followed up with these women one year after the initial mammogram to verify their breast cancer status.
For women in the 18-24 group, no tumors were detected in breast tissue on the initial mammogram screening. This data is in agreement with a report distributed by the American Cancer Society that indicates cancers in this age group are rare.
The American Cancer Society report estimates that during 2002-2006, that 1.4 out of every 100,000 women between the ages of 20 and 24 were diagnosed with cancer. Investigators concluded that mammograms were ineffective at detecting cancers in these young women with no signs, symptoms, or family history of cancer.
For the 35 to 39 subgroup comprised of 62% of the women included in the study. For every 10,000 women screened, 1266 were called back for a followup test, and only 16 of those women truly had cancer. The remaining 1250 women were put through the pain and discomfort of a breast biopsy and the unnecessary worry and anxiety about a possible cancer diagnosis.
Stated another way, 12% of women screened for breast cancer under the age of 40 will endure worry, wasted time and expense for a false-positive test (results indicate you have cancer when you don’t). The data indicates that less than 1% of women screened at this age who have an average risk of breast cancer (for example, don’t have a family history of the disease) actually have the disease.
That number does not increase for women in this age group who have first-degree relatives with breast cancer. However, more women were accurately diagnosed with breast cancer under the age of 40 if they had a mammogram performed after detecting a lump in their breast.
These findings are extremely important since nearly 200,000 US women are expected to be diagnosed with breast cancer each year. The earlier the disease is detected, the sooner patients can be treated, and the better their chances for survival.
Breast cancer is typically detected by a normal monthly breast self-examination, a clinical breast exam, or mammography. Approximately 15 percent of women in their 40s detect breast cancers through mammography. From 2002-2006, 95% of new cases and 97% of breast cancer deaths occurred in women aged 40 and older.
The American Cancer Society recommends that women in their 20s and 30s should perform monthly breast self-examinations and receive clinical breast exams at least every three years. Their guidelines also suggest that women 40 and above should receive mammograms annually.
Women who are considered at high risk for developing breast cancer should have mammograms starting at 30. Risk is determined by the presence of mutations in the breast cancer susceptibility genes, BRCA1 and BRCA2; a family history of breast and/or ovarian cancer; or prior history of radiation therapy. Studies show that mammograms given to women in these risk categories can detect cancers earlier and increase the odds for long-term survival.