For example, some breast cancer treatments can cause symptoms usually linked to the menopause in women, such as hot flushes and weight gain.

Prostate cancer treatment usually (but not always) makes patients impotent, and reduces their interest in sex. The treatment may also cause lethargy, weight gain and hot flushes.

Although hormone therapy can have unwanted effects, most patients feel quite well during their treatment. Some patients don't notice any problems – everyone is different.

Your doctors will tell you about the benefits, risks and side-effects of the treatment being offered to you. You will then need to agree to it before it can start. This is called giving your consent. Don't be afraid to ask questions if there is anything you don't understand.