Apr 3, 2012 8:31 PM
April 3, 2012 -- Taller women may be more likely to develop ovarian cancer, a new study suggests.
What's more, an increasing body mass index or BMI also raises the risk for ovarian cancer among women who have never taken hormones during menopause.
Exactly how increasing height is tied to ovarian cancer risk is unclear. Still, these findings are important, as the average height among people in wealthy countries has increased by about 1 cm (or 0.4 inches) per decade, and the average body mass index or BMI is also on the rise, study authors write. The findings are published in PLoS Medicine.
In 2012, about 22,000 women will be diagnosed with ovarian cancer and about 15,500 women will die from the condition, according to the American Cancer Society.
Researchers culled data from 47 studies that took place in 14 countries, many in Europe and North America. In the end, their analysis included more than 25,000 women with ovarian cancer and about 81,000 women without ovarian cancer. The taller the women were, the greater their risk for ovarian cancer. For about every 2-inch increase in height, there was a 7% increase in risk for ovarian cancer.
"Risk goes up by a very small amount with increasing height," says Elizabeth A. Poynor, MD. She is a gynecologic oncologist and pelvic surgeon at New York City's Lenox Hill Hospital.
Although the study poses more questions than it answers regarding height, "it speaks to what makes us taller now than we were in the past," she says. "We are better fed now."
This risk did not change in the face of other risks for ovarian cancer, including age, family history, and age at first menstrual period.
Among women who never used hormones around menopause, there was a 10% increase in risk for every 5-point increase in BMI. This increase in risk was not seen in women who had used hormone therapy.
"The height finding is hard to explain," says Joanne Mortimer, MD. She is the director of the women's cancer program at the City of Hope Cancer Center in Duarte, Calif.
The obesity finding makes more sense. "We know obesity does increase risk of several cancers." She says the best defense is to eat a healthy diet, exercise regularly, and maintain a normal weight. "You can't shorten yourself, but you can make yourself non-obese."
Jacob Rotmensch, MD, is the director of gynecology oncology at Rush University Medical Center in Chicago. "You can't change your height," he says. "Time will tell us the significance of this finding. It needs further investigation."
The best thing a woman can do today is to be aware of her risks for ovarian cancer. These may include:
"Review your family history," Poynor tells WebMD. "Try to get information going back three generations, including the history on your father's side."