Cancer Drug Tamoxifen is Worth the Risk
Why would anyone take tamoxifen if the side effects are so dreadful?
In some breast cancers, oestrogen can cause tumour cells to grow: tamoxifen blocks the activity of oestrogen in the breast tissue and stops growth of the cancer. It is standard treatment after breast cancer surgery. When a woman is diagnosed with the disease, she is tested to see if her tumour is ‘oestrogen positive’. If it is, she can take tamoxifen. It is a tablet taken every day for five years after the operation, which has been shown to significantly increase chances of survival in the ten years after surgery.
So what are the downsides?
Minor side effects include nausea, diarrhoea and headaches. The more serious side effects come from tamoxifen blocking oestrogen in the body. In pre-menopausal women menopause-like symptoms – hot flushes, night sweats, mood swings and depression – come on suddenly and dramatically instead of gradually. But fertility is not affected and symptoms go away when you stop taking the drug.
Side effects of the drug can include nausea, diarrhoea and headaches
Can it be taken to prevent breast cancer in high-risk women?
Theoretically yes, but this has never been licensed. This is because the largest trial concluded that the potential benefits from taking tamoxifen simply for prevention did not outweigh known risk factors.
So there are more serious risks?
Yes. When taking tamoxifen, the chances of womb cancer, though still low, are significantly increased. But this risk is outweighed by the increased survival rates for breast cancer.
