Study Links Lung Cancer With Removal of Ovaries
A new study, published in the in the International Journal of Cancer, looks at lung cancer and may change the common practice of removing both ovaries when a hysterectomy is done. It has become common to remove both ovaries as a way to prevent ovarian cancer.
Epidemiologists from the Université de Montréal, the Research Centre of the Centre Hospitalier de l'Université de Montréal and the INRS - Institut Armand-Frappier were surprised to find that women who had their ovaries surgically removed are at an increased risk of developing lung cancer.
Researcher Anita Koushik states, “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. 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 researcher studied 422 women who were diagnosed with lung cancer in 1996 and 1997. They were compared to 577 control subjects who did not have lung cancer. The women were treated at 18 hospitals across Montreal, Quebec, Canada. The researchers assessed socio-demographic characteristics, residential history, occupational exposures, medical and smoking history, and menstruation and pregnancy histories.
For the study, women were considered menopausal if their menstrual periods had stopped naturally, surgically (by hysterectomy with bilateral surgical ovary removal) or because of radiation or chemotherapy. Women who had at least one remaining ovary and who still had their menstrual periods at the time of diagnosis/interview were classified as premenopausal. Among participant with natural menopause, the median age for attaining menopause was 50 years old; among those with non-natural menopause, it was at 43 years.
While smoking remains the predominant cause of lung cancer, other identified potential risk factors include: secondhand smoke; occupational exposures such as asbestos, chromium, or arsenic; environmental exposures such as domestic radon; indoor pollutants; previous lung disease; dietary factors; family history; and genetic factors. This study suggest there may be a link to the impact of plummeting hormone levels with ovarian removal.
So while removal of the ovaries do decrease the risk of breast cancer and virtually eliminated their risk of ovarian cancer, it appears to almost double the risk for lung cancer among those women who never used hormone therapy.
About the Study
The article “Characteristics of menstruation and pregnancy and the risk of lung cancer in women,” published in the International Journal of Cancer, was authored by Anita Koushik and Jack Siemiatycki of the Université de Montréal and Research Centre of the Centre Hospitalier de l'Université de Montréal and Marie-Elise Parent of the INRS - Institut Armand-Frappier.