Neoadjuvant progesterone therapy for primary breast cancer: rationale for a clinical trial

The hormonal milieu at the time of surgery may influence mortality and disease-free survival in patients with primary breast cancer. Indeed, there is evidence that circulating unopposed estrogen is detrimental and that the presence of circulating progesterone results in an improved disease-free and overall survival rate. Thus patients who receive neoadjuvant progesterone therapy may have a better outcome. A randomized controlled trial in which women with primary breast cancer receive either progesterone or placebo before surgery is urgently needed to confirm this hypothesis.