Circulating Immune Complexes in Human Breast Cyst Fluids: Relationship with Intracystic Immunoglobulin and Electrolyte Levels

Human gross cyst breast disease and cystic fluid: bio-molecular, morphological, and clinical studies

For more than one and a half century the cystic disease of the breast has been recognized as the most frequent female benign breast lesion. Although some conundrums and controversies exist about the relation between gross cysts and breast cancer, recent evidence suggests that the multidisciplinary study of gross cystic breast disease (GCBD) may be a powerful tool for predicting the natural history of the multifaceted gross cyst pathology. A lot of papers have been published on breast cyst fluids (BCF) concerning biochemical, hormonal and morphological aspects, demonstrating that the intracystic fluid contains a wide variety of components (such as ions, lipids, proteins, enzymes, growth factors and antigens) and suggesting that their profile provides additional knowledge on both physiopathology and etiologic pathways of human gross cystic breast disease. The aim of this overview is the critical evaluation of all data accumulated in the last thirty years, in order to highlight the utility of biochemical and epidemiological studies to identify gross cysts, if any, at higher breast cancer risk.

Lipid-associated sialic acid levels in human breast cyst fluids

Benign mammary gross cystic disease is the most common breast lesion. Women with apocrine changes of epithelium lining the cysts are at higher risk for developing breast cancer than the normal female population. Sialic acid has drawn considerable interest because of carbohydrate aberrations in malignant cells. The current investigation determined the concentrations of lipid-associated sialic acid (LASA) in 62 breast cyst fluids and sera. Data analyses show a significant increase in the mean values of LASA in metabolically active apocrine cysts when compared to the cysts with Na+/K+ > 3 (flattened cysts) (p < 0.001). The greater LASA levels in cyst fluids with lower intracystic Na+/K+ ratios could represent an altered expression of biosynthetic activity of the surrounding apocrine cell surface sialoglycolipid metabolism, providing a possible explanation of why women with apocrine cysts may be at greater cancer risk and being useful in further studies on functional stage changes in the cysts and their relationship to breast cancer.