Biochemical analysis of breast cyst fluid as a possible predictor of breast carcinoma development.

The occurrence of breast cancer in patients with gross cystic disease is 2-5 times higher as compared to control group of women. During 3 years, 183 cyst fluid samples were analyzed in 129 females, in 30 patients of them the samples were analysed repeatedly. The distribution of the Na+/K+ ratio, considered as the measure of cancer risk, was found to be bimodal. In repeated analyses the type I cyst fluid markedly predominated (Na+/K+ < or = 4.0). A direct dependence on this ratio was found in the concentration of glucose, albumin, carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA) and its specific form, TPS; an indirect dependence was found for the level of uric acid, phosphates, alkaline phosphatase (ALP) and alpha-amylase (AMS). The predominance of apocrine metaplasia cells released into the cyst fluid is characteristic of type I cysts. A definitive assessment of significance of these parameters will be enabled by a long-term follow-up of the disease in the respective patients.