Skin cancer patients are at an increased risk for developing a new, different form of the disease later in their lifetime, new research suggests.

According to a study conducted by researchers at Queen's University Belfast, people who are diagnosed with melanoma, the most deadly form of skin cancer, have double the risk of developing a new primary cancer.

For those who are diagnosed with non-melanoma skin cancer, their risk of a new primary cancer increases by up to 57 per cent.

The research team, led by Prof. Liam Murray, analyzed data from nearly 23,000 patients in Northern Ireland who had either melanoma or non-melanoma skin cancer. They compared the data to cancer incidence rates in people who did not have a history of skin cancer.

The findings are published in the British Journal of Cancer.

Through the course of the study, the researchers also found that patients who had been diagnosed with non-melanoma skin cancer were almost twice as likely to develop melanoma, and also were at an increased risk for developing smoking-related cancers.

According to Murray, there are a number of explanations for why someone with one type of cancer may be at greater risk for developing another form.

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

Murray explained the risk of smoking-related cancers among non-melanoma patients by saying that smokers may lead more unhealthy lifestyles, which could include excessive sun exposure.

According to the Canadian Cancer Society, 4,600 new cases of melanoma were diagnosed in Canada in 2008.

Risk factors include:

• excessive sun exposure
• having a large number of moles
• having light skin, hair or eyes
• a family history of the disease
• a history of sunburn