Immunohistochemical expression of the mucin-type glycoprotein A-80 and prognosis in human breast cancer.

Immunohistochemical expression of the tumour associated mucin-type glycoprotein A-80 was investigated in a series of 173 breast cancer patients with a clinical follow-up between 13 and 19 years. A routine immunoperoxidase technique was used in formalin-fixed, paraffin-embedded surgical tumour specimens. One hundred and fifty of 173 tumours (87%) immunostained with MAb A-80. The degree of A-80 immunoreactivity was related to the tumour grade but not to lymph node status, tumour size, or nuclear DNA distribution pattern. In univariate analysis the degree of A-80 expression was found to be of significant prognostic value both in node negative and in node positive breast cancer patients (P = 0.03). Patients with non-A-80 immunoreactive tumours had significant longer distant metastases-free survival times and fewer relapses than women with carcinomas composed of A-80 immunoreactive tumour cells. This prognostic value was reduced in a multivariate analysis, including lymph node status, tumour size, and nuclear DNA distribution pattern, but retained borderline significance (P = 0.08). In conclusion, the findings of this study indicate that expression of the mucin-type glycoprotein A-80 as determined by immunohistochemistry seems to be related to clinical outcome in breast cancer patients.