Breast cancer and timing of surgery during menstrual cycle: a 5-year analysis of 248 premenopausal women.

In the present report, we retrospectively analyzed the impact of the timing of surgery during menstrual cycle on disease‐free and overall survival of 248 premenopausal patients with stage I/Il breast cancer who underwent surgery followed by anthracycline‐containing adjuvant chemotherapy. With a median follow‐up of 5 years, no statistically significant differences were observed in disease‐free or overall survival between women operated upon during the follicular (days 0–14) and the luteal (days 15–32) phase of the menstrual cycle. The impact on disease‐free and overall survival of lymph‐node status, tumor size and hormone receptor expression, but not of the phase of the menstrual cycle at the time of surgery, was confirmed by univariate and multivariate analysis.