Provocative new research suggesting that the timing of breast cancer surgery in the menstrual cycle can dramatically affect its success has ignited a fierce debate among cancer specialists.
Recent studies have found that pre-menopausal women newly diagnosed with breast cancer survive far longer when the operation to remove the tumor is performed during the second half of their monthly cycle.
"It seems that there's something biochemical that happens when surgery is performed late in the menstrual cycle that increases the probability that tumor cells that have spread beyond the breast will die," said Dr. Peter Paul Rosen, a pathologist at Memorial Sloan-Kettering Cancer Center in New York City, who directed one of the new studies. Almost all women who die of breast cancer succumb to cancer cells that have migrated to and multiplied in distant parts of the body.
But cancer surgeons are deeply divided about whether the small studies have hit upon a significant finding that should now alter care, or merely a statistical fluke.
A handful of surgeons are convinced enough that they are advising women to postpone breast surgery for a few weeks. At Guy's Hospital in London, surgeons now perform all breast surgery at least 12 days after the patient's last menstrual period. The disadvantage of the short-term delays "will probably be outweighed by the potential long-term benefit," Dr. I.S. Fentimen, writing for a team of Guy's doctors, in a recent issue of the British medical journal Lancet.
But many other doctors are skeptical. "I have looked at the data and I don't believe there is any relationship at all," said Dr. William Wood, chief of surgery at the Emory University Medical Center in Atlanta. "I don't think there's a harm in waiting and if a patient asked to I would try to honor the request. But to me it's a superstition, like tying a rabbit's foot around your wrist."