MAMMOGRAPHY AND THE DIAGNOSIS OF
Breast cancer is an increasingly common disease amoung American women. It's incidence has been increasing steadily during the past several decades. Only recently has a reduction in mortality from breast cancer been demonstrated. The cause and, therefore, the prevention of breast cancer remains elusive. Early diagnosis is the only proved method by which the current death rate from this disease can be reduced. In 1995 nearly 50,000 American women will lose their lives to breast cancer. Many of these lives can be saved by early detection. The most effective tools for early detection of breast cancer are regular physical examination by a health care provider, diligent monthly breast self examination and mammography.
Detection Of Tumors:
Mammograms are capable of finding breast cancer two to three years before it becomes manifest as a palpable lump. These early tumors are typically curable by local removal and radiation treatment without the need for mastectomy.
With increasing frequency women are now availing themselves of regular mammography as the value of this examination becomes increasingly apparent to health care providers and to the lay public. Unfortunately mammography is not 100% accurate. Approximately 10% of breast cancers which can be detected by palpation are not demonstrated on even high quality mammograms due to a variety of factors related to the biology of the malignancy, location within the breast and the texture of breast tissue.
Standards For Screening:
Optimal mammography is highly dependent upon the technical quality of the examination and upon the skill and experience of the radiologist interpreting the study. Both the American College of Radiology and the Federal Food and Drug Administration implementing the provisions of the 1994 Mammography Quality Standard Act have established rigid criteria to ensure the compliance of all mammography facilities in the United States with standards of technical and interpretive performance. This helps to ensure American women that their mammography examination is performed and interpreted in accordance with established quality measurements.
There are many radiologists in the United States who specialize in mammography and breast imaging. These individuals by virtue of their particular interest and expertise in this field of medical imaging generally provide examinations and interpretations of the highest quality. These radiologists are usually members of the Society of Breast Imaging. Those with outstanding achievements in this field are awarded the designation Fellow of the Society.
Interpretation Of Findings:
Even under the most optimal circumstances, however, both the art and science of mammography are not perfect. The signs of early breast cancer on mammograms are frequently subtle and there is a significant overlap between mammographic findings which reflect a benign process and those which are a harbinger of malignancy.
For this reason, biopsies of breast tissue (the extraction of tissue in an area identified as possibly abnormal on a mammogram) are more commonly interpreted by pathologists as reflecting a benign as distinguished from a malignant process. Nationwide, only 1 of every 3 to 4 breast biopsies prompted by mammographic findings yield malignant tissue.
Other breast imaging techniques particularly ultrasound examination are frequently helpful in further characterising abnormalities in the breast which may either appear on a mammogram or be palpable at clinical examination.
With increasing frequency biopsies of breast tissue performed with small needles have been replacing open surgical biopsy for abnormalities which are visible either by mammography or ultrasound. Many radiologists in the United States now perform this procedure. Specialized and sophisticated equipment is needed to perform these image guided biopsies either using a computer assisted stereotactic technique or real time ultrasound.
Until reliable means of preventing breast cancer are developed, the early detection potential of regular, high quality mammography remains the most important weapon in the fight againsts breast cancer.