Advances in AI could spare thousands of men unnecessary treatment and side effects. Men with prostate cancer which has an intermediate risk of spreading when they are given radiotherapy are currently offered six months to three years of hormone therapy at the same time. But AI, which looks for biological patterns in the cancer cells taken from individual men's biopsies at the point of diagnosis, can identify those who would not benefit from hormone therapy. This could save men from the side effects of hormone therapy including fatigue, hot flushes, reduced muscle strength, weight gain around the waist and changes to their sex life such as a low libido or problems getting an erection. Doctors now know hormone therapy, which starves tumours of the male sex hormones which fuel them, only helps some men.