PROSTATE-SPECIFIC ANTIGEN PRODUCTION IN THE FEMALE BREAST - ASSOCIATION WITH PROGESTERONE

Prostate-specific antigen (PSA) is produced by the female breast Prior in vitro evidence suggests that PSA expression in breast epithelial c ells is regulated by androgens and progestins but not estrogens, The p urpose of this study was to determine whether (a) PSA expression in br east nipple aspirate fluid (NAF) and in serum is influenced by progest erone (PG); (b) the ability to obtain NAF decreases with repeated brea st aspirations; and (c) PSA in NAF correlates with abnormal NAP cytolo gy, Eight pre-and three postmenopausal women with no breast cancer ris k factors were enrolled in a pilot study and had NAF and serum collect ed every 3-4 days for a month to evaluate the influence of serum PG, l uteinizing hormone, estradiol, and follicle-stimulating hormone on PSA in serum and in NAF, NAF was obtained in 99% (112 of 113) of aspirati on visits, Median, mean, and peak NAF but not serum PSA levels were hi gher in pre-than in postmenopausal subjects, NAF PSA levels were assoc iated with the rise or peak in serum PG in seven of eight premenopausa l women (seven of seven with a PG surge) and in zero of three postmeno pausal women, Considering all 11 women, there was an association betwe en NAF PSA and PG (P = 0.005) but not luteinizing hormone, estradiol, or follicle-stimulating hormone, NAF volume did not significantly chan ge over time, Atypical hyperplasia (9%) and hyperplasia without atypia (36%) were identified in the NAF of a subset of the subjects, Median, mean, and peak levels of NAF PSA (P = 0.05, 0.05, and 0.10, respectiv ely) were higher in subjects with normal versus hyperplastic cytology, PSA production in the breast increases in association with PG, With a spiration every 3-4 days, NAF volume does not significantly decrease o ver time, NAF cytology and PSA levels in NAF may help identify women a t increased breast cancer risk, Changes in biomarkers of breast cancer risk in NAF (including PSA and cytology) may predate mammographic abn ormalities, NAF may, therefore, be useful as a breast cancer screening tool for young women who are not recommended to undergo mammography a nd as an adjunct to screen women who have mammograms performed.