Prognostic significance of serum IgE levels in primary breast cancer.

Serum IgE was measured in presurgical sera from 166 nonallergic women admitted to a comprehensive, multidisciplinary study of primary, operable breast cancer. During the follow-up period, which averaged 48 months, there were 71 recurrences. Patients were divided into two groups: those with IgE levels greater than the geometric mean value of 24 I.U. and those with levels less than the mean. The rate of tumor recurrence was significantly greater for the IgE greater than 24 group (p less than 0.03). IgE remained a significant prognostic indicator when evaluated by Cox regression analysis in conjunction with other known prognostic factors including: number of positive lymph nodes, clinical stage, menopausal status, estrogen receptor status, mitotic grade, tumor diameter, breast feeding history, and age of patient (p less than 0.015). IgE was not correlated with any of these known prognostic factors in individual analyses. We conclude that serum IgE level is a significant, independent prognostic indicator in primary breast cancer.