A new treatment approach may help thousands of women with early-stage breast cancer avoid premature menopause and preserve their ability to have children, U.S. researchers said.
A study, presented at the annual meeting of American Society of Clinical Oncology (ASCO) in Chicago, showed that women who received AstraZeneca PLC's drug goserelin along with chemotherapy were 64 percent less likely to develop premature menopause than women who had chemotherapy alone. They were also more likely to have successful pregnancies, and the treatment appeared to improve survival.
Chemotherapy often causes premature ovarian failure, or early menopause. Doctors think that active ovaries are more susceptible to chemo damage, and that making the ovaries go dormant and stopping a woman's monthly cycles might help shield them from harm. It might even improve survival, a study found.
The study involved 257 women around the world under age 50 with breast cancers whose growth is not fueled by estrogen. They all had standard chemo and half also had monthly shots of goserelin, a drug to lower estrogen and temporarily put the ovaries at rest. Its main side effects are menopause symptoms - hot flashes and vaginal dryness, the AP reported.
Doctors then tracked the women to see how the treatments affected fertility.
After two years, full results were available on 135 participants. Only 8 percent of those given the shots became menopausal versus 22 percent of the others who didn't get them. There were 22 pregnancies in the drug group versus 12 in the other one.
That's encouraging, but firm comparisons can't really be made because not all women may have been trying to conceive, and other factors such as a partner's fertility play a role, the AP reported.
Still, "the difference was enough that in spite of all the limitations in the study, we were pretty convincingly able to see an effect," said the study's leader, Dr. Halle Moore of the Cleveland Clinic, according to the AP.
The benefits go beyond preserving fertility, said Dr. Kathy Albain, a breast cancer specialist at Chicago's Loyola University and one of the study leaders.
"Some women don't care about having children" after breast cancer, but would like to avoid "being jolted into early menopause" by chemo treatment, she said.
About a quarter of breast cancers occur in women under 50, affecting some 40,000 to 50,000 women each year. Unlike natural menopause, which occurs gradually, chemotherapy can suddenly throw a woman into full-blown menopause. In about half of these women, this condition is permanent, eliminating the chance for a future pregnancy.
"This is the first time anything has been shown to prevent this," said Albain. "I think these findings are going to change our clinical practice."
During the study's design, researchers were concerned that adding the hormone treatment might hurt the women's breast cancer treatment, Reuters reported.
But the results suggest women who got goserelin were 50 percent more likely to be alive four years after starting treatment compared with those receiving the standard therapy.
National Cancer Day
To mark National Cancer Day, the American Cancer Society noted that there are 14.5 million cancer survivors in the United States and that number is expected to grow to 19 million over the next decade.
More cancers are cured, more people are living longer with the disease and people are living longer in general, which boosts the number of cases and survivors because the risk of developing cancer rises with age, the American Cancer Society noted in a report by the AP.
The report came on the third day of the annual meeting of ASCO, the world's largest group of specialists who treat cancer. This year's event, ASCO's 50th, brings together 30,000 doctors, researchers and pharmaceutical agents from around the world.
"Scientifically, the field of oncology has never been more exciting," said Clifford Hudis, president of ASCO, according to the French news agency AFP.
Hudis cited new targeted therapies that take aim at the cellular functions of tumors, leading to progress against some difficult to treat cancers. Also, immunotherapy is an exciting field that uses a patient's own immune system to attack tumors, and is showing promise against melanoma, leukemia, and a handful of other cancers.
"We have made incredible progress in 50 years," said Jyoti Patel, a cancer specialist at Northwestern University, according to AFP
"The scientific breakthroughs in cancer are occurring at a breathtaking pace and are being translated into new drugs and devices that benefit patients more quickly than ever before," said Richard Schilsky, chief medical officer of ASCO, AFP reported.
However, he warned that this progress is in jeopardy due to a shortage of research funds, particularly from the National Institutes of Health, the largest government funder of US scientific research wich in 2013 had a budget of $28.9 billion.
Some information for this report provided by Reuters, AFP and AP.