Peri-operative biology in primary breast cancer: a credible therapeutic target.

Over the last 25 years, there has been a growing body of basic science, modeling, and clinical data suggesting that the peri-operative period in the treatment of primary breast cancer is dynamic and can be manipulated to improve long-term outcomes. Clinical data have demonstrated early peaks of hazards for recurrence and emphasized the relationship of these to peri-operative events. More recently, clinical trial data with surgical oophorectomy at different times in the menstrual cycle, peri-operative progesterone, and anti-inflammatory drugs suggest that interventional studies are particularly well justified, given the increasing recognition of the costs both financially and clinically of current systemic regimens.