In the proposed study breast cancer patients will be treated with a combination of a beta-blocker and COX2 inhibitor (or placebo) before, during and after surgery. (A control group of healthy women will serve as untreated controls). The variables which will be examined are: number and activity of NK cells, levels of Th1 and Th2 cytokines, serum stress hormones and angiogenic factors, and the ability of leukocytes to produce Th1 and Th2 cytokines as a result of in vitro stimulation.