For Breast Cancer Patients, Timing of Surgery May Affect Chances for Survival
Nov. 15, 1999 (Minneapolis) -- New research provides powerful data for women facing breast cancer surgery: The timing of surgery within the menstrual cycle can significantly effect long-term survival. A study by British researchers shows that women with breast cancer who are still menstruating, or are premenopausal, have significantly better chances of surviving the disease when surgery is performed before day three or after day 12 of their menstrual cycle. The findings were reported in the November issue of the journal Cancer.
While researchers have debated the issue of timing for breast cancer surgery for many years, this study may help resolve the controversy. "There is mounting evidence that the timing of surgery within the menstrual cycle has a significant effect on prognosis in premenopausal women with breast [cancer]," according to Ian S. Fentiman, MD and colleagues of Hedley Atkins Breast Hospital at Guy's Hospital in London.
The study looked at over 100 premenopausal women with operable breast cancer. For each woman, the point in the menstrual cycle on the day of surgery was determined beforehand. The women underwent one of two surgical procedures: breast conservation therapy or modified mastectomy. They were monitored over 10 years.
The results of the study revealed that timing of surgery within the menstrual cycle did affect survival. During the luteal phase, which typically occurs during the last two weeks of a woman's menstrual cycle, researchers found the patients' overall 10-year survival rate following surgery was 75%. But when surgery was performed during the follicular phase, between day three and 12 of the menstrual cycle, her 10-year rate of survival was only 45%.
Another important factor that influenced survival, according to the researchers, was whether or not the women's estrogen receptors (ER) and progesterone receptors (PR) were positive or negative. Hormones, particularly estrogen, play a significant role in breast cancer prognosis. The timing of the surgery, combined with the nature of the hormone receptors -- the sites on the cell's surface that binds with the hormones -- helped the scientists to determine which women would have the best overall survival rates.