In 1928 Dr George Papanicoloau, a Greek immigrant living in New York, discovered he could detect pre-cancerous cell changes in the cervix. This led to the development of the smear test which has meant millions of women worldwide have not had to face cancer.
Dr Papanicoloau's great niece Olga Stamatiou speaks to Laura Jones.
(Image shows Dr Papanicoloau examining a slide in a laboratory. Credit: Getty Images)