• Whether the timing of mastectomy during the menstrual cycle influences the prognosis of premenopausal women with breast cancer is controversial. We retrospectively reviewed the cases of 97 regularly menstruating women treated for operable stages of breast cancer. At operation, 55 women were in the perimenstrual phase of the menstrual cycle (days 0 through 6 and days 21 through 36) and 42 were in the periovulatory phase (days 7 through 20). No relationship could be identified between the timing of surgical treatment and subsequent recurrence or survival. The timing of biopsy was also not associated with prognosis. We conclude that no delay of surgical treatment for breast cancer need be based on the phase of the menstrual cycle of premenopausal women.
(Arch Surg. 1993;128:309-313)