LONDON: It is the most effective treatment for breast cancer known to medical science, and has been administered to hundreds of thousands of women over the past decade. But researchers have now found that tamoxifen can trigger tumours in the womb, and cause deep vein thrombosis. The study, carried out by Canadian researchers, raises serious questions about the future use of tamoxifen as a preventative drug, the Cancer Research Campaign admitted last week. The Canadian study reveals that tamoxifen “is not a magic pill which will bring an end to cancer”, said Dr Lesley Walker, the campaign’s director of cancer information.

However, the CRC stressed that the drug is still perfectly safe for use in helping cancer patients, but needs to be reconsidered as a possible preventative treatment for healthy women. The associated risks of triggering other ailments suggest it is unsuitable, despite recent hopes it could provide protection for middle-aged women.

The Health Analysis and Modelling Group used a highly sophisticated computer model to project what would happen to women given tamoxifen. They found that apart from the drug’s known side-effects - bleeding, reduced bone density and flushes - there would be a significant danger to them from other diseases. In particular, the team, led by Dr Phyllis Will, found that those who take tamoxifen face a four-fold risk of getting endometrial cancer (a tumour of the womb lining) and a doubled risk of deep vein thrombosis. Both conditions are potentially lethal. Giving tamoxifen to healthy women could therefore have very serious consequences, the group warn in their paper, a danger that was also stressed by Kate Wall, head of clinical trials at the Cancer Research Campaign.

“This clearly sounds a warning about the use of tamoxifen, but it does not mean we should abandon it totally,” she said. ”Both endometrial cancer and deep vein thrombosis are relatively uncommon. We have to balance the risk of women getting these diseases with the danger of them going on to develop breast cancer which, sadly, is fairly common in the West. Women who have just had existing tumours surgically removed are at an especially high risk of developing breast cancer again, and there is no question that tamoxifen should continue to be administered to them.’” Only those at special risk - such as women with close relatives who had developed breast cancer before they were 50 years old - are now likely to be considered as recipients. —Dawn/The Observer News Service.