Alcohol consumption linked to subtypes of breast cancer, but not all

Alcohol consumption linked to subtypes of breast cancer, but not all

Regular alcohol intake raises the risk of developing lobular and hormone receptor-positive breast cancer, but does not appear to be linked to invasive ductal carcinoma risk, says a report published in JNCI (Journal of the National Cancer Institute), August 23rd issue. This is the first major study to look at a possible relationship between alcohol intake and breast cancer risk by subtype, the authors wrote.

Some previous studies had looked into whether there might be a link between alcohol consumption and hormone receptor-positive (estrogen receptor and/or progesterone receptor-positive) breast cancer. However, not many examined breast cancer link by histology, or whether a tumor is in the milk ducts (ductal) or in the milk-producing lobules (lobular), the authors explained.

Christopher I. Li, M.D., Ph.D., and team at Fred Hutchinson Cancer Research Center carried out an observational study of a subset of patients in the Women's Health Initiative (WHI) study, conducted between 1993 and 1998, including 87,724 postmenopausal women aged between 50 and 79 years.

The following data related to 2,944 females in the WHI study who had developed invasive breast cancer was collected and assessed:

  • tumor subtypes and hormone status
  • alcohol consumption
  • demographic and lifestyle characteristics
  • family history of diseases
  • reproductive history
The women were classed as:
  • Women who never consumed alcohol
  • Women who used to consume alcohol, but did not any more
  • Women who currently drank alcohol - these were grouped into 6 categories, depending on how much they drank. Drinking ranged from a maximum of 1 drink per week, to at least 14 drinks per week.
Their research showed a stronger link between alcohol consumption and lobular carcinoma than ductal carcinoma, and more strongly related to hormone-receptor- positive breast cancer than hormone-receptor-negative breast cancer.

This study confirms previous ones which found a link between alcohol consumption and hormone-positive breast cancer risk, as well as three previous case control studies that identified a stronger link between alcohol and lobular carcinoma. Risk did not appear to vary according to the type of alcohol consumed.

The researchers wrote:

We found that women who drank one or more drinks per day had about double the risk of lobular type breast cancer, but no increase in their risk of ductal type breast cancer. It is important to note that ductal cancer is much more common than lobular cancer accounting for about 70 percent of all breast cancers whereas lobular cancer accounts for only about 10-15 percent of cases.

The fact that the researchers had no data regarding the women's past and subsequent alcohol usage - but only their alcohol intake at the beginning of the study - was a limitation for the study's findings, the authors pointed out.

"Alcohol Consumption and Risk of Postmenopausal Breast Cancer by Subtype: the Women's Health Initiative Observational Study"

Christopher I. Li, Rowan T. Chlebowski, Matthew Freiberg, Karen C. Johnson, Lewis Kuller, Dorothy Lane, Lawrence Lessin, Mary Jo O'Sullivan, Jean Wactawski-Wende, Shagufta Yasmeen, Ross Prentice

JNCI (Journal of the National Cancer Institute), August 23rd, 2010. doi:10.1093/jnci/djq316

Breast Cancer and Alcohol: How Much is Safe? (Video Medical And Professional 2020).

Section Issues On Medicine: Women health