On the basis of clinical observations that some women with fibrocystic
breast disease experienced resolution of the disease on eliminating m
ethylxanthines from their diet, it has been suggested that coffee inta
ke might be related to breast carcinogenesis. The relationship between
coffee (mostly expresso and mocha), decaffeinated coffee and tea inta
ke and breast cancer risk was therefore considered, combining data fro
m two case-control studies, conducted in Italy between 1983 and 1994.
Cases were 5,984 women, below age 75, with histologically confirmed br
east cancer, and controls were 5,504 women admitted to hospital for a
wide spectrum of acute, non-neoplastic, non-hormone-related diseases.
The odds ratios (ORs) were estimated from multiple logistic regression
equations including terms for study/centre, age, education, body mass
index, smoking status, total alcohol intake, age at menarche and meno
pause, parity and age at first birth, use of oral contraceptives, use
of hormone replacement therapy, history of benign breast disease and f
amily history of breast cancer. No relationship was observed between c
offee intake and the risk of breast cancer. The multivariate ORs were
1.17 (1.03-1.33), 1.17 (1.04-1.33), 1.21 (1.06-1.37) and 0.96 (0.83-1.
11) for women drinking < 2, 2, > 2 to < 4 and greater than or equal to
4 cups/day compared to non-drinkers. Decaffeinated coffee was consume
d only by 6-7% of cases and controls and the corresponding OR was 0.84
(0.72-0.98). Tea consumption was also low and not associated with the
risk of breast cancer (OR 0.94, 95% CI 0.85-1.03). No significant het
erogeneity was found for coffee intake across strata of age at diagnos
is, education, body mass index, smoking status, total alcohol intake,
age at menarche and menopause, parity, age at first birth, ever use of
oral contraceptives, hormone replacement therapy, history of benign b
reast disease and family history of breast cancer. Thus, this study, b
ased on a large data set, allows us to exclude the hypothesis that cof
fee intake is related to breast cancer risk in this Italian population
. (C) 1998 Rapid Science Ltd.