Ending Periods Helps Cancer Survival
Breast Cancer and Menstruation Link: Chemo Patients More Apt to Survive if Periods Stop
Dec. 15, 2006 (San Antonio) -- Breast cancer
chemotherapy can cause menstruation to cease, and now a
study shows that's a good thing.
Austrian researchers found women live longer and have fewer relapses if
their periods stop.
In fact, women who continue to have a period despite chemotherapy might
benefit from additional treatment to lower their levels of cancer-fueling estrogen,
says Michael Gnant, MD, a breast cancer specialist at the Medical University of
Breast Cancer and Menstruation
The study, presented at the annual San Antonio Breast Cancer Symposium,
included more than 500 premenopausal women taking chemotherapy drugs for breast
About half stopped having their periods because of the cancer-killing
All had hormone-receptor-positive tumors. The growth of such breast cancers
is fueled by hormones; this is the most common type of the disease.
By 10 years after starting treatment, women whose periods had stopped were
40% less likely to suffer a recurrence than those whose didn't, the study
They were also 10% less likely to die, Gnant says.
Further analysis showed that almost all the benefit was in women under 40 at
the time they started therapy, he says.
Chemo May Exert One-Two Punch
The results suggest chemotherapy has a dual effect in some women: It not
only directly kills cancer cells, but also works indirectly by suppressing the
ovaries, Gnant says.
"When you suppress the ovaries and stop menstruation, there is less
estrogen available. Since estrogen stimulates hormone-receptor-positive tumors
to spread, taking it away helps," he tells WebMD.
Whether taking ovary-suppressing drugs can help women who continue to
menstruate despite chemotherapy is a question being studied in large, ongoing
Such drugs, which include Zoladex and Synarel, cut estrogen production to
levels women have after menopause.
While awaiting those studies' results, women whose menstruation doesn't stop
despite chemotherapy may want to talk to their doctor about taking an
ovary-suppressing drug, says Kathy Albain, MD, a breast cancer specialist at
Loyola University of Chicago Medical Center.
"I already tell my younger patients with hormone-receptor-positive
breast cancer that there is probably a survival advantage to shutting down
their period," she tells WebMD. "But not all want [the drugs]; some
women may want to have a family."