In an article in the Journal of Clinical Pathology, Dr Sezgin Ismail of the Department of Pathology at the University of Wales College of Medicine says various studies have shown that Tamoxifen has harmful side effects. The drug has been used for some 25 years to treat breast cancer. Last year the USA stopped a study to test whether it had a preventive effect on women with a family history of breast cancer. But European trials have not shown any significant preventive role for the drug. Dr Ismail says it is likely Tamoxifen use will increase substantially in the years to come and reports of side effects will increase.
Womb lining The main side effects noted in research up until now relate to the womb lining.
More studies have been done on post-menopausal women, because they are more likely to suffer from breast cancer and to take Tamoxifen. Dr Sezgin says research shows significant thickening in the womb lining of women taking the drug on a long-term basis. Also present in the womb lining are polyps, cysts and other abnormalities that are risk factors for cancer. For those taking it over a five-year period, the cases had quadrupled. Even in the discontinued US study women taking Tamoxifen were almost twice as likely to develop endometrial cancer as those on placebos.