About 80 percent
of breast cancers not discovered
by mammography are found
by women themselves.
There is not one accurate method of early detection
Limitations of Early Detection
Breast Self-Examination
Scientific research shows that breast self-examination by itself cannot reduce the rate of women dying from breast cancer. What that means is that breast self-examination is not a form of cancer detection; rather, it is a procedure that helps women understand how their breast tissues normally feel. Breast self-examination is not a replacement for annual clinical breast exams and mammograms.
Another limitation to self-examination is that some women become too worried that they have breast cancer while performing the exam. If you experience too much anxiety while performing breast self-examination, talk to your doctor about it.
Mammograms
It is important to understand that the benefits of mammography far outweigh the risks and inconvenience involved.
Mammography screening is the current basis for early breast cancer detection. It has been proven to detect breast cancer at an earlier stage and to reduce the number of women dying from the disease. However, mammography is not perfect. Studies have shown that routine mammography screening can reduce the number of deaths from breast cancer by about 25–30% among women between the ages of 50 and 70. A lesser benefit was seen among women aged 40–49. Screening mammography cannot eliminate all deaths from breast cancer because it does not detect all cancers, including some that are found by physical examination. Up to 15% percent of breast cancers are missed by mammography screening. Some tumors may also develop too quickly to be identified at the most treatable stage using the standard screening intervals. In addition, it is technically difficult to consistently produce mammograms of high quality, and interpretation is subjective and can vary among radiologists. Mammograms are particularly difficult to interpret in women with dense breast tissue, which is particularly common in young women. The dense tissue interferes with identification of abnormalities associated with tumors, leading to a higher rate of abnormal test results (both positive and negative) in these women.
These difficulties associated with dense tissue are especially problematic for women who wish to begin screening at a younger age because of their family history or genetic test results.
Mammographic screening can also lead to further invasive, expensive, and uncomfortable follow-up procedures, such as surgical biopsies, in which a suspicious area of the breast is removed and examined by a pathologist. As many as three-quarters of such biopsies are negative, meaning there is no cancer. Therefore, don’t be afraid to undergo a biopsy; the large majority are negative and are done to absolutely make sure that there is no problem.
Another limitation of mammography is that the methods for classifying the abnormalities it detects are based on the appearance of the tissue structures. Some of the breast abnormalities mammography can detect may not be aggressive malignancies requiring intensive treatment, but rather pre-malignant or non-invasive conditions that will not progress to life-threatening disease. Because of this uncertainty, doctors tend to be cautious, treating all such questionable abnormalities as dangerous. As a result, some women may be unnecessarily treated for a noncancerous condition and are affected by the psychological distress associated with such a diagnosis.
