July 21, 2009 — Women who have premature menopause because of medical interventions are at an increased risk of developing lung cancer, according to a new study published in the International Journal of Cancer. The startling link was made by epidemiologists from the Université de Montréal, the Research Centre of the Centre Hospitalier de l’Université de Montréal and the INRS—Institut Armand-Frappier.
“We found that women who experienced non-natural menopause are at almost twice the risk of developing lung cancer compared to women who experienced natural menopause,” says Anita Koushik, a researcher at the Université de Montréal’s Department of Social and Preventive Medicine and a scientist at the Research Centre of the Centre Hospitalier de l’Université de Montréal. “This increased risk of lung cancer was particularly observed among women who had non-natural menopause by having had both their ovaries surgically removed.”
The scientists studied 422 women with lung cancer and 577 control subjects at 18 hospitals across Montreal, Quebec, Canada. They assessed socio-demographic characteristics, residential history, occupational exposures, medical and smoking history, and (among women) menstruation and pregnancy histories.
“A major strength of this study was the detailed smoking information which we obtained from all study participants; this is important because of the role of smoking in lung cancer and because smokers generally have lower estrogen levels than non-smokers,” says Dr. Koushik. “Although smoking is the dominant cause of lung cancer, we know other factors can play an important role in enhancing the impact of tobacco carcinogens; this research suggests that in women hormonal factors may play such a role.”