The association of measured breast tissue characteristics with mammographic density and other risk factors for breast cancer.
BACKGROUND
We have examined the relationships between the measured properties of breast tissue and mammographic density and other risk factors for breast cancer, using breast tissue obtained at forensic autopsy and not selected for the presence of abnormalities.


METHODS
We used randomly selected tissue blocks taken from breast tissue slices obtained by s.c. mastectomy at the time of forensic autopsy to measure histologic features using quantitative microscopy. The proportions of the biopsy occupied by cells (estimated by nuclear area), glandular structures, and collagen were determined. These measurements were examined in relation to the percent density in the faxitron image of the tissue slice from which the biopsy was taken and other risk factors for breast cancer.


RESULTS
The percent mammographic density was associated with the proportion of the area of the biopsy occupied by nuclei, both epithelial and nonepithelial, and by collagen and the area of glandular structures. Several other risk factors for breast cancer, notably body weight, parity, and number of births, and menopausal status, that are associated with variations in mammographic density, were also associated with differences in one or more of these tissue features.


CONCLUSIONS
All risk factors for breast cancer must ultimately exert their influence by an effect on the breast, and these findings suggest that, for some risk factors, this influence includes an effect on the number of cells and the quantity of collagen.
Li
Tong
T
Division of Epidemiology and Statistics, Ontario Cancer Institute, 610 University Avenue, Toronto, Ontario, Canada M5G 2M9.
Sun
Limei
L
Miller
Naomi
N
Nicklee
Trudey
T
Woo
Jennifer
J
Hulse-Smith
Lee
L
Tsao
Ming-Sound
MS
Khokha
Rama
R
Martin
Lisa
L
Boyd
Norman
N
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001940:Breast / Q000033:anatomy & histology* / Q000166:cytology / Q000378:metabolism; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D002452:Cell Count; D003094:Collagen / Q000378:metabolism; D005260:Female; D006801:Humans; D008327:Mammography; D008875:Middle Aged; D012307:Risk Factors
D003094:Collagen