There is a link between alcohol and breast cancer. Researchers have known that for a while — the former puts you at risk for the latter. But few studies have looked at alcohol’s impact on breast cancer when you break it down into specific tumors. A new study did just that.
Published in the “Journal of the National Cancer Institute,” it found that alcohol increases the risk of “lobular” and “hormone receptor-positive” breast cancer, but not necessarily “invasive ductal” tumors.
While some studies have shown alcohol use is more strongly related to risk of hormone receptor-positive breast cancer (linked with the estrogen and/or progesterone receptors), not many have looked at whether it influences ductal or lobular breast cancer. “Ductal” refers to the milk ducts and “lobular” refers to milk-producing lobules in the breast.
Researchers conducted an observational study, set within the huge Women’s Health Initiative study, which included nearly 88,000 postmenopausal women between 50 and 79 years old. They broke it down and honed in on the 2,944 women who developed invasive breast cancer. They assessed what kind of cancer it was, hormone status, and alcohol consumption, and gathered family history and other pertinent bits of information.
Women were split into groups: those who never drank; those who formerly drank; and those who currently drink. Drinkers were grouped into six categories according to the average number of drinks per week, starting from less than one drink per week to more than 14 drinks per week.
The study found that alcohol use is more strongly related to the risk of lobular carcinoma than ductal carcinoma, and more strongly related to hormone-receptor-positive breast cancer than hormone-receptor-negative breast cancer. These results confirm previous findings of an association of alcohol consumption with hormone-positive breast cancer risk, as well as three studies that identified a stronger association of alcohol with lobular carcinoma. It did not matter what type of alcohol was consumed.
They found that women who had one or more drinks a day had about double the risk of lobular type breast cancer, but no increase in their risk of ductal type breast cancer. Importantly — and good news for women who like the odd alcoholic beverage — ductal cancer is much more common than lobular cancer, accounting for about 70% of all breast cancers. Lobular cancer accounts for only as much as 15% of cases.
In the interests of alcohol’s effect on health, every bit of information we have is valuable.