PROSTATE-SPECIFIC ANTIGEN LEVELS IN NIPPLE ASPIRATE FLUID CORRELATE WITH BREAST-CANCER RISK

Despite the fact that breast cancer is the most common non-cutaneous c ancer and a leading cause of cancer deaths in women, accepted markers of breast cancer risk miss up to 40% of these tumors, Moreover, screen ing methods involving the analysis of tissue or cells are limited by t he need for a surgical biopsy, Nipple aspiration is a quick, efficient , noninvasive method to obtain breast epithelial cells, the cells at r isk for transformation to carcinoma, Prostate-specific antigen (PSA), a protein thought to be specific to the prostate but recently found in a subset of breast tumors, has been correlated with improved survival , The purpose of this study was to measure PSA in a group of women wit h increasing breast cancer risk (no risk or family history of breast c ancer, precancerous mastopathy, and invasive cancer) and determine if PSA correlates with risk, Nipple aspirate fluid was obtained from the intact breast and from surgical specimens using a modified breast pump , PSA was then measured in the fluid using a highly sensitive and spec ific immunofluorometric procedure. PSA was found at levels ranging fro m 0-13,423 ng/g of total protein, and there was a significant relation ship between PSA level and breast cancer risk (P = 0.001), That is, al l women with no risk factors and 90% of those with a family history ha d high PSA levels, whereas 68% of subjects with precancerous mastopath y or invasive cancer had low PSA levels, PSA was higher in premenopaus al subjects (P = 0.002), After adjusting for the effect of menopausal status, there remained a significant association between PSA and breas t cancer risk, These findings suggest that PSA in nipple aspirate flui d may be a useful marker of breast cancer risk.