Prognostic significance of the immunohistochemical reaction to human milk fat globule antibodies in node-negative and node-positive breast cancer.

The status of axillary lymph nodes in patients with breast cancer is important prognostically but does not identify all patients who will have long or short survival. To determine if the immunohistochemical reaction of tumor cells to human milk fat globule (HMFG) antibodies will define prognosis more specifically, we examined patients with node-negative disease and patients with more than three positive nodes, the extremes of the prognostic spectrum. In both node-negative and node-positive groups, patients who relapsed were matched by age at diagnosis, tumor size, histologic type, and receptor status, with patients who remained disease-free for a minimum of 48 months. Patients with poor survival had a higher proportion of poorly differentiated cancers. The ability to generate antigens recognized by HMFG antibodies was decreased in patients with recurrent disease, but this was significant only in patients with node-positive tumors. Tumors of patients who remained disease-free were more likely to have a pattern of membrane staining, while cytoplasmic staining was more frequent in those who relapsed. The results suggest that immunohistologic response to HMFG antibodies may assist in identifying cancers with poor prognosis, supplementing the prediction derived from node status.