marlboro smoking lady

Cigarettes May Have…

Published on June 16th, 2008 15:06

Scientists say that cigarettes may lower the risk of breast cancer in women with a gene mutation related to high rates of the disease. But there are other health risks of smoking. Jean-Sebastien Brunet, lead author of a study, a researcher at the Women's College Hospital of the University of Toronto in Canada. says: "Smoking may reduce breast cancer risk for these women, but cigarettes sharply increase the incidence of other cancers. This study is interesting scientifically, but it should not encourage anyone to smoke."

The study investigated the breast cancer history of 372 women who all had mutations of the BRCA1 or BRCA2 genes. About 80% of the participants will develop breast cancer during their lifetime. Half of the women in the study were nonsmokers and half were smokers. Brunet noted that the rate of breast cancer was 54% lower among heavy smokers than among nonsmokers. He said: "If a woman smoked up to four pack years, the reduction was 35%. For a four or more pack years, the reduction was 54%."

Only women with the BRCA gene mutation took part in the study. This mutation happens in only 1 of every 250 women. Depending on some ethnic groups, the incidence can be as high as one in 50. Brunet said the research was scientifically useful because it suggests that some action of smoking or of some of the 1,300 compounds in cigarette smoke may be protective against breast cancer.

Some breast cancers have been related to the female hormone – estrogen, and cigarette smoking lowers production of estrogen. Smoking also is linked to a decreased risk of endometrial cancer and to early menopause. Nevertheless, smoking increases the risk of other, more dangerous cancers, such of the throat, lung and pancreas.

Brunet and his team say: "We did everything we could to test the data, but we would really like for someone to replicate the study just to prove that our data set is correct." he said.

Dr. John A. Baron of Dartmouth Medical School and Dr. R. W. Haile of the University of Southern California said: "The study certainly should not be taken as encouragement for women with (the) mutations to smoke, but that it does raise the possibility that something in cigarette smoke could be of benefit for such women."