Immunohistochemical study of Muc1, Muc2 and human gastric mucin in breast carcinoma: Relationship with prognostic factors

We investigated the expression of mucin core proteins, Muc1, Muc2, and human gastric mucin (HGM) immunohistochemically in 5 non-invasive, 62 invasive ductal carcinomas and 3 mucinous carcinomas of the breast and statistically examined the relationship with prognostic factors. Muc1 was expressed in almost all breast carcinomas and there was a reverse correlation with tumor size (r=-0.25). However, Muc1 was not significantly correlated with the other tumor characteristics such as lymphocytic infiltration, axillary lymph node metastasis, TNM and plasma levels of CA153. Muc2 and HGM were expressed in 5 cases each in invasive ductal carcinomas, 0 and 3 in non-invasive ductal carcinomas, and 2 and 1 in mucinous carcinomas, respectively. Muc 2 expression correlated with lymph node metastasis. HGM was found in the tumors without lymph node metastasis and lower levels of serum CA 153.