Deaths from breast cancer fall dramatically in UK and USBMJ 2000; 320 doi: https://doi.org/10.1136/bmj.320.7247.1428/a (Published 27 May 2000) Cite this as: BMJ 2000;320:1428
Deaths from breast cancer in Britain have fallen by nearly a third in the past 10 years thanks largely to wider and more prolonged use of the antioestrogen drug tamoxifen. A similar but smaller decline in deaths from the disease—about 25%—has been observed among US women since 1990.
“This is the best decrease in national death rates that has ever been seen with any common cancer that has been produced by treatment,” commented Professor Sir Richard Peto from the Imperial Cancer Research Fund's cancer trials unit at the University of Oxford, who helped to compile the figures, which are published in the Lancet (2000;355:1822).
He added, “During the 1990s, 20000 breast cancer deaths that could have happened in Britain didn't, and this year we will have 13000 rather than 17000 deaths from the disease.” Earlier diagnosis, better surgery, chemotherapy, and radiotherapy have all contributed to the improved survival, but the most important influence on outcome has been the widespread and prolonged use of tamoxifen, he said.
Deaths from breast cancer soared by 26% in the United Kingdom between 1950 and 1989, giving one of the worst death rates from the disease in western Europe. But between 1989 and 1999 deaths from the disease declined from 51 per 100000 women to 35 per 100000.
This drop is more significant than in the rest of western Europe, where tamoxifen was not as readily adopted as in the United Kingdom.
In the United States, where mortality remained fairly steady at around 40 per 100000 women throughout the 1970s and '80s, wider use of tamoxifen since the late 1980s has reduced the death rate to about 32 per 100000 in 1998.
Data from 55 randomised trials involving the use of tamoxifen after surgery show that five years of treatment with tamoxifen reduces the 10 year risk of relapse from 42% to 26% and halves the risk of developing a new tumour in the other breast.
These beneficial effects of tamoxifen are seen in women of all ages with hormone sensitive breast cancer—about 80% of older women and 50% of younger women.
About one million women worldwide are taking tamoxifen, and, although the five year regimen has been used in the United Kingdom for a long time, it is still being underused in many countries, according to Dr Christina Davies, tamoxifen trial coordinator at the Clinical Trial Service Unit in Oxford.
Two trials (ATLAS and ATTOM) are currently investigating whether giving tamoxifen for longer than five years has any additional benefits; the results will not be known, however, until 2010.