It hasn’t been that long since I posted an update about breast cancer – but there is already a lot more to post about!

A paper in the Archives of Internal Medicine presents data from 116,000 women shows that those who have infertility issues due to an ovulation disorder also have a lower incidence of breast cancer – 25% less. Of course it is just a correlation, but indicates that there may be no long term consequences to infertility treatment as the risk was lowest in the women who had been treated for infertility with induced ovulation.

Another correlational study supports the previous evidence that weight gain increases the risk of breast cancer. This one was published in the International Journal of Cancer and states that there is around a 70% increase in the chance of developing breast cancer in women who gained more than 60 lbs between ages 20 and menopause. This is in contrast to women who gained no more than 20 lbs. over the same period.

The Journal of the National Cancer Institute has a report on 2437 women who have survived breast cancer – those who decreased their fat intake after treatment by around 40% had a lower return of cancer than those who didn’t. The effect may be due to the weight loss that went along with the fat intake reduction rather than the reduced fat level itself. Also, women with estrogen receptor-negative breast cancer may see the effect more than women with estrogen receptor-positive cancers.

Along those same lines, another study published in the Archives of Internal Medicine suggests that women who eat more red meat have a greater chance of developing estrogen receptor-positive breast cancer. Specifically, those who ate greater than 1.5 servings of red meat on an average day had nearly twice the chance of getting cancer than women who only had 3 or less servings in a week. This effect could be due to either hormone residues, iron or other carcinogens in the meat.

A few weeks ago Science published a report that shows that one of the active ingredients in the pill RU-486 may also help to stop the formation of breast cancer in mice with the BRCA-1 mutation. Progesterone can stimulate the development of breast cancer since it accelerates cell division. However, mifepristone (one of the ingredients in RU-486) blocks the action of progesterone.

There is lots more research out there – but I’m out of time today! I’ll try to keep my blog updated as much as possible with new research.

(Technorati Tags: breast cancer, brca-1, red meat, fat)