EXPRESSION OF THE CD15 ANTIGEN (LEWIS-X) IN BREAST-CANCER

The expression of the cell adhesion molecule CD15 (also known as Lewis x) by breast cancers and by adjacent normal and benign breast epithel ium was investigated in a series of 98 tumours. Immunohistochemistry w as performed on paraffin sections using the anti-CD15 monoclonal mouse IgM antibody Dako-M1. Some 35% of cancers expressed CD15, as did 45% of normal and 60% of hyperplasia. No association was observed between cancer cell staining, or any epithelial staining (cancer, benign and n ormal), and tumour size, histological grade, nodal status, age at diag nosis or the frequency of 'events' (recurrence or death). Chi-squared tests in each case were non-significant, The pattern of CD15 expressio n by breast cancer was frequently associated with the leading edge of invading tumour or with the outer edge of boli of carcinoma in situ, p ossibly suggesting a potential role in invasiveness, and with cancer c ells trapped intravascularly, possibly suggesting a role in metastasis .