The virus that causes cold sores could help to treat the advanced stages of malignant melanoma, the most serious type of skin cancer a person can develop, which results in around 65 deaths every year in Ireland.

A research team has carried out a preliminary study into whether a genetically modified version of the herpes simplex virus can be used safely on humans. This follows previous research which found that a mutant form of the virus improves the survival times of animals with malignant melanoma tumours.

Five patients with advanced skin cancer took part in the study. Two of the participants were given one injection of the modified virus each, two received two injections and one patient was given four injections.

The result was that the virus appeared to kill tumour cells without harming surrounding tissue in the three patients who received two or more injections.

The Scottish research team described the results as encouraging but did emphasise that the study was still in its very early stages.

Malignant melanoma is a very dangerous type of cancer that begins in the layer of the skin that tans (pigmentation-system), usually developing from an existing mole on the back, shoulders or the back of the legs. Early discovery and treatment are vital.

Latest figures from the National Cancer Registry of Ireland show that around 600 people develop it annually, with around 65 deaths resulting.