Clinicalpathological and pathogenetic study of lymphocytic mastitis / 细胞与分子免疫学杂志

ABSTRACT

Aim To explore clinicalpathological features and the pathogenesis of lymphocytic mastitis, an uncommon breast benign disease. Methods The clinical pathological characteristics of 7 patients with lymphocytic mastitis were studied retrospectively. All cases were evaluated by using paraffin-embedded sections and by immunohistochemical staining with mouse anti-CD20, -CD45RO, and -CD68 antibodies. T and B lymphocytes infiltrated in the lobules of mammary gland were quantitatively analyzed according to stereoscope. The glucose regulation protein 94 (grp 94)/glycoprotein 96(gp 96), a member of heat shock protein family was also investigated in these cases by using immunohistochemical staining. Results It was showed that 4 cases were women suffering from insulin dependent diabetic mellitus (IDDM). One case was a woman without diabetic history. The history of the other two cases was not clear. The histopathological features of all 7 cases were lobulitis, perilobulitis and catheter ductitis with infiltration of lymphocytes accompanied with atrophy of lobule in mammary glands and homologous fibrosis of stroma. The result of immunohistochemical staining showed that most of infiltrated lymphocytes were B lymphocytes, while the small proportion of the cells were T lymphocytes, and the difference was significant(P〈 0.01). There was the expression of grp 94 in the cytoplasm of epithelium cells of lobules and ducts in normal mammary glands. A proportion of lymphocytes infiltrated in lobules and perilobules expressed grp 94. Some infiltrated cells expressed CD68. Conclusion A portion of lymphocytic mastitis is related closely to insulin dependent diabetic mellitus. Both humoral immunity and cellular immunity are probably involved in the pathogenesis of lymphocytic mastitis. Because of its unique pathologic and clinical features, lymphocytic mastitis should be defined as an independent mastitis and distinguished from other chronic inflammatory and fibrosing conditions in breast.