Researchers in the United States are starting human clinical trials of a vaccine implant which targets skin cancer.
The implant - the size of a fingernail - is placed under the skin and re-programmes a patient's immune system to destroy cancerous melanoma cells.
The technique was trialled successfully in mice in 2009 where it was found that those who received two doses of the vaccine showed complete regression of their tumours.
The vaccine was developed by Professor David Mooney of Harvard University.
