Study: Coffee May Help Fight Breast Cancer

Coffee May
Reduce Breast Cancer Risk in Women with BRCA1 or BRCA2 Mutations

Among women with BRCA1 or BRCA2 gene mutations, consumption of six
or more cups of coffee per day was linked with a 69% reduction in risk of breast
cancer. These results were published in the International Journal of
Cancer.

Inherited mutations in two genes—BRCA1 and BRCA2—have been found to
greatly increase the lifetime risk of developing breast and ovarian cancer.
Alterations in these genes can be passed down through either the mother’s or the
father’s side of the family. Because not all women with a BRCA1 or BRCA2
mutation develop cancer, there is interest in identifying factors that increase
or decrease the likelihood of breast cancer.

Coffee consumption could potentially modify breast cancer risk by
influencing estrogen metabolism.  Previous studies of coffee and risk of
breast cancer have been inconsistent; some have suggested a protective effect of
coffee and some have suggested no effect of coffee.

To evaluate the effect of coffee consumption on risk of breast
cancer in a large population of women with a BRCA1 or BRCA2 mutation, an
international group of researchers conducted a study among 845 mutation carriers
with breast cancer (cases) and 845 mutation carriers without breast cancer
(controls). The two groups were matched by mutation type (BRCA1 or BRCA2), year
of birth, and country of residence (US, Quebec, other Canada, or Israel). There
were 652 pairs of women with BRCA1 mutations and 193 pairs with BRCA2
mutations.

Information about coffee consumption was collected by questionnaire.
Women were asked about the age at which they started drinking coffee, age at
which they stopped, and their usual daily consumption. Women were asked to
distinguish between caffeinated and decaffeinated coffee. The analysis was
limited to coffee consumption prior to the case’s breast cancer diagnosis. Women
who consumed different levels of coffee were compared to women who had never
consumed coffee.

After accounting for number of previous births, smoking, oral
contraceptive use, alcohol consumption, body mass index and age, consumption of
six or more cups of caffeinated coffee per day was linked with a 69% reduction
in risk of breast cancer. There was no significant effect of lower levels of
coffee consumption, though there was a trend of decreasing breast cancer risk
with increasing coffee consumption. Consumption of decaffeinated coffee did not
affect breast cancer risk.

When the analysis considered women with BRCA1 mutations and BRCA2
mutations separately, the link between high levels of coffee consumption and
decreased risk of breast cancer was most apparent for women with BRCA1
mutations. This may be due in part to the larger number of women in the study
with BRCA1 mutations.

The researchers conclude that “relatively high coffee consumption
may reduce breast cancer risk among women with BRCA1 and/or BRCA2 gene
mutations.” They note that it will be important to confirm this finding in other
studies.

Reference: Nkondjock A, Ghadirian P, Kotsopoulos J
et al. Coffee consumption and breast cancer risk among BRCA1 and BRCA2 mutation
carriers. International Journal of Cancer. 2006;118:103-107.

Related News:  Effect of Pregnancy on Breast Cancer Risk Varies Between BRCA1
and BRCA2 Mutation Carriers (10/27/05)

SOURCE: http://patient.cancerconsultants.com/news.aspx?id=35259