Scientists suggest the reovirus, which usually causes mild colds or stomach upsets, has the power to shrink tumours.
They have created the viral vaccine that can be injected into the bloodstream, “hitching a ride” on blood cells and avoiding the immune system.
Previous research has focused on injecting the virus into tumours.
The reovirus treatment acts both like chemotherapy and a vaccine. It kills tumour cells while at the same time causing an anti – cancer immune response.
Dr Kevin Harrington, from the Institute of Cancer Research in London who co – led the study, said: ”Viral treatments like reovirus are showing real promise in patient trials.”