Skin cancer patients risk developing another type of the disease, according to a new study carried out by Northern Ireland researchers.

They found that those being treated for the disease could be more than twice as likely to get another cancer compared with the general population.

Previous studies have shown that people suffering from one cancer are at higher risk of developing another.

Researchers for this Belfast-based study, published in the British Journal of Cancer, decided to focus their attention on people with skin cancer.

They analysed data from the Northern Ireland Cancer Registry (NICR) for between 1993 and 2002, including 20,823 people treated for non-melanoma skin cancer and 1,837 people with melanoma.

Compared with the general population, people with non-melanoma skin cancer were up to 57% more likely to develop another type of cancer.

They were almost twice as likely to go on to develop melanoma and had an increased risk of smoking-related cancers.

The risk was much higher in those who had had squamous cell carcinoma (SCC) than those who had basal cell carcinoma (BCC).

Among those with melanoma, the risk of developing another cancer was more than double.

In this research, patients developed another cancer that was unrelated to the first. This is different from when cancer spreads to other parts of the body.

Malignant melanoma is the most serious type of skin cancer and each year in the UK, more than 9,500 people are diagnosed with it and more than 2,000 people die.

Over 76,500 people are diagnosed with non-melanoma skin cancer in the UK each year.

Professor Liam Murray, one of the authors, based at Queen’s University, Belfast, said: “This study confirms that people with a diagnosis of skin cancer have an increased future risk of developing another type of cancer, especially one of the other types of skin cancer or a smoking-related cancer - and for those with melanoma the risk may be more than double that of the rest of the population.

“There are several possible explanations for this link. Sun exposure is an important risk factor for all types of skin cancers so patients who have had one type of skin cancer may be more likely to develop other types as well.

“Alternatively, a new skin cancer may be more likely to be detected in patients who are monitored following their first diagnosis of skin cancer.

“The increase in smoking-related cancers may be because smoking predisposes to skin cancer as well as other cancers or because people who smoke may be more likely to have generally unhealthy lifestyles including excessive sun exposure.”