Tamoxifen (Nolvadex) Reduces Oestrogen Receptor Positive Breast Cancer

A major review by several research bodies now has clear evidence that Tamoxifen reduces the risk of oestrogen receptor breast cancer.

The review includes research from Cancer Research UK, European Institute of Oncology, Royal Marsden Hospital/Institute for Cancer Research and the Australia New Zealand Trials Group. They reviewed trials where Tamoxifen was given for at least 3 years compared to being administered placebo as a control.

Tamoxifen had no effect on breast cancers negative for ER, but reduced ER positive cancers by 48%. Side-effects from the drug can be reduced by use of a lower dose, concomitant use of a low dose aspirin and selection to exclude women with a risk for thromboembolism and endometrial cancer.

However, Tamoxifen cannot yet be recommended as a preventative agent, except possibly for women with a very high risk who wish to avoid or delay prophylactic mastectomy.

(Source: Lancet 2003;361:296-300.)