Babies Safe for Most Women After Completion of Breast Cancer Treatment
Studies presented recently at the European Breast Cancer Conference in Barcelona have found that women who have been treated for breast cancer can have babies without increasing their risk of dying from their cancer. The findings suggest that pregnancy may even have a protective effect.
Historically, the Royal College of Obstetricians and Gynecologists does not advise against pregnancy for breast cancer survivors, but recommends that women wait for up to five years after treatment, depending upon the aggressiveness of the tumor. The American Cancer Society suggests 2 years.
Hatem Azim, of the Institute Jules Bordet in Brussels, and researchers completed a meta-analysis of 14 trials carried out in Belgium and Italy that occurred between 1970 and 2009 involving a total of 1417 pregnant women with a history of breast cancer and 18059 breast cancer survivors who were not pregnant.
The findings did not support the notion that hormonal changes associated with pregnancy, particularly estrogen, could prompt a cancer to recur or become more aggressive. The findings did reveal that patients who became pregnant after breast cancer diagnosis had a reduction in the risk of death of 42% compared with those who did not get pregnant.
Azim said that although estrogen is linked to breast cancer, the protective effect of pregnancy could be explained by higher levels of the hormone inhibiting cancer cells or pregnancy may help to boost the immune system. During pregnancy, women often follow a more healthful diet and see their doctor more regularly, possibly making them naturally protected. Pregnancy and breast feeding have been associated with a lower overall chance of developing breast cancer later in life.
"I hope this changes what doctors tell their patients," Azim said. "There's no reason to tell women who survive breast cancer not to get pregnant."
Cancer Expert Maria Leadbeater, but does advise women to discuss pregnancy with their doctor. Women who need hormone therapy, for example, are advised against getting pregnant for the five years of treatment they receive.
Some experts do not agree with all of the findings. "This has the strength of a meta-analysis. but it's controversial," said Dr. Massimo Cristofanilli, chairman of medical oncology at Fox Chase Cancer Center in Philadelphia. "Previous studies have shown that these women had no worse outcome. This may be too optimistic."
For example, another study of almost 3,000 Australian breast cancer patients found that women who were diagnosed with a tumor within a year of giving birth were almost 50 percent more likely to die compared with other women of the same age. On the other hand, if the women were diagnosed during pregnancy, they had roughly the same odds of survival as other women.
"I don't think anybody knows what the timeframe is from having been treated and when it's a good idea to have a child," said Leena Hilakivi-Clarke, a professor of oncology at Georgetown Lombardi Comprehensive Cancer Center in Washington, D.C. "But if the tumor has been satisfactorily treated and there is nothing growing in the breast, then the pregnancy should be protective."