C-reactive protein in nipple aspirate fluid: relation to women's health factors

Proteins expressed in nipple aspirate fluid (NAF) have been associated with breast cancer risk and may serve to detect inflammatory or premalignant states. Obesity, hyperlipidemia, and metabolic syndrome are associated with increased rates of breast cancer and are systemic markers of chronic inflammation.

The aim of this study was to determine if one NAF protein, C-reactive protein (CRP), associated elsewhere in the human with cancer, relates to reproductive, nutrition, and body composition and activity factors.

Women (n = 59) aged 30 to 64 years from the midwestern United States and Kenya were evaluated regarding the relation between reproductive (age, pregnancy, and breast-feeding indices), nutrition (serum lipids, serum, or NAF carotenoid), body composition and activity (activity, waist-hip ratio, fat percentage (% fat), and body mass index [BMI]) factors and CRP in NAF.

Age at first pregnancy (p < .05), gravidity (p < .05), wean time from breast-feeding last baby (p < .05), serum triglycerides (p = .01), % fat (p < .05), and BMI (p < .05) were related significantly to CRP levels in NAF. A model derived from selective women's reproductive, nutritional, and body composition and activity factors significantly (p < .05) accounted for the variance in breast microenvironment inflammation as measured by CRP in NAFs.

Detecting CRP in NAF may indicate local mammary inflammation, which has been associated with carcinogenesis. Specific NAF risk modeling that addresses reproductive, nutritional, and body composition and activity factors may be used for further advances in the prevention of breast cancer and the early detection and treatment of the disease.