Mammogram Density,Nipple Aspirate Fluid &amp; Breast Cancer Risk
Creators: name: University Of California Office Of The President
Publisher: name: University of California Office of the President
publisherIdentifier: https://ror.org/00dmfq477
publisherIdentifierScheme: ROR
Year: 2024

description: Mammography has long been established as the leading method for the early detection of breast cancer. In addition to its value for the diagnosis of cancer, investigators have found that certain non-cancerous breast changes that appear in the mammogram may be indicators of increased future risk of breast cancer. Recently, several studies have shown that the amount of dense areas seen on mammograms ('mammographic density') is a sign of increased risk of breast cancer. These areas of density indicate the amount of glandular and connective tissue (as opposed to fat, which is the third type of tissue in the breast) within the breast. Two recent large-scale studies found that risk of breast cancer is increased in proportion to the amount of dense areas in mammograms. It was found that women with areas of mammographic density occupying more than 75% of the mammogram had a four- to five-fold increased risk of breast cancer compared to women with area of density occupying less than 10% of the mammogram. The risk increased in proportion to the amount of the breast occupied by areas of density. This increased risk has persisted throughout the period for which data is available for these women, which at present is 5 to 10 years after the mammogram. (Using other funds, the breast cancer risk of these women will continue to be assessed at appropriate intervals.) 
 
 
 
 
 
 
 
 Our group has pioneered the use of nipple aspirates of breast fluid for epidemiologic studies of the changes in the structure and function of breast cells and the biochemistry of the breast. Nipple aspiration employs a breast pump to obtain small amounts of fluid which can be employed as a kind of a "Pap smear' for study of breast disease, cancer, and precancerous conditions. Between 1975 and 1980, we obtained nipple aspirate fluid (NAF) from 2,162 women who underwent mammography at the Breast Screening Center of Northern California at Merritt Hospital, Oakland. We found that women whose NAFs contained unusual or "atypical" breast epithelial cells had a five-fold increased risk of breast cancer compared to women who did not yield any breast fluid. Among premenopausal women with atypical cells, the risk was increased 15-fold over non-yielders of NAF. This higher risk has held true, persisting for the 10- to 18-year period for which breast cancer statistics are available. (The breast cancer risk of these women will likewise continue to be assessed as data becomes available.) 
 
 
 
 
 
 
 
 The purpose of this study is to determine if the combination of mammography and NAF analysis improves our ability to estimate a woman's risk of developing breast cancer. Our study will use data already collected, including age, race, breast cancer risk factors, NAF cytology and, in addition, current breast cancer status as of December 1995. However, it will be necessary for the radiologists to re-measure all 2,162 mammograms for area of mammographic density before carrying out the epidemiological and statistical analyses. The fact that the status of all the women is currently known will make it possible to determine the extent to which the prediction of breast cancer risk is enhanced by the combination of area of mammographic density and cytologic diagnosis. 
 
 
 
 
 
 
 
 If combining the methods of area of mammographic density and nipple aspiration cytology is found to significantly improve the prediction of women at risk above either method alone, this approach could be used to separate women at highest risk from those at lowest risk, and would be of particular usefulness in premenopausal women with dense breasts, and women with a family history of breast cancer, or a prior benign biopsy. This information would be useful for recruitment of subjects for preventive trials, for women undergoing genetic counseling, and for targeting preventive interventions.