In the latest study, Danish researchers followed the health and lifestyles of 17,647 nurses from 1993.
By 2001, 457 were diagnosed as having breast cancer.
Those who drank excessively on just one day during the week had a 55 per cent increased risk of developing breast cancer.
But it was the minority of women who binge drank from Friday through to Sunday, that were at most risk. Doctors from the Centre for Alcohol Research in Copenhagen warned such drinking increased the risk by an alarming 150 per cent.
Those drinking large amounts - 22-27 units - across the week had an increased risk of 130 per cent.
The study showed with each additional drink during the week, the risk of developing the cancer increased by four per cent.
A Cancer Research UK study estimated around one in 20 cases of breast cancer each year can be blamed on drinking.
But the risk escalates with several drinks consumed in a short space of time.
Binge-drinking in the study was classified as four or more units of alcohol in a session - UK health guidelines recommend no more than two or three units for women. A unit of alcohol is a half pint of lager, a small glass of wine or a pub measure of spirits.
More than one in five young women is a binge drinker, according to official UK figures. They show 22 per cent of women aged 16 to 24 had drunk heavily on at least one day during the previous week.
Writing in the European Journal of Public Health, Dr Lina Mirch who led the study said: "The impact of alcohol consumption in weekdays or weekends has not been addressed in previous studies of risk of breast cancer.
"To minimise the risk of breast cancer our data imply that women should not do any binge drinking or drink larger amounts of alcohol."
She said it was possible that weekend binge drinkers drank more on each drinking occasion than weekday bingers - which would explain the higher risk associated with weekend bingeing.
It is unclear how drinking alcohol promotes breast cancer but it may work by raising levels of the sex hormone oestrogen in the body.
Dr Mirch said: "The detrimental effect of binge drinking suggests a biological different effect of alcohol or its metabolites, when high serum concentrations of alcohol might be related to peaking levels of oestrogens.
"This could lead to an enhancement of the harmful effects of alcohol on breast cancer."
Dr Mirch warns that most women have little to fear from enjoying a drink occasionally.
She said: "The risk is minor for moderate levels of weekly alcohol intake, but increases for each extra drink consumed."
Heart specialists say older women benefit from modest drinking because heart disease cases soar after the menopause but it has to be balanced against an increase in breast cancer.
Dr Alison Ross, of Cancer Research UK, said: "Even small amounts of alcohol can increase the risk of breast cancer."
She said the advice to women was to limit the amount of alcohol they drank and try to keep a healthy body weight.
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