Skin cancer may increase risk of other cancers later in life

Australian author on the paper, Professor Rodney Sinclair, Professor of Medicine at the University of Melbourne and Director of Dermatology at Epworth HealthCare said that the risk decreased significantly with increasing age, but it remains higher compared with individuals who have never had NMSC.

"The risk for developing any cancer subsequent to NMSC decreases significantly with increasing age: 23 times higher risk for those under 25 years of age; 3.52 for those 25-44 years of age; 1.74 for those 45- 59 years of age; and 1.32 for those older than 60 years. Published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research, NMSC is considered the most common type of skin cancer, relatively easy to treat if detected early, and rarely spreading to other organs. "Our study shows that NMSC susceptibility is an important indicator of susceptibility to malignant tumors and that the risk is especially high among people who develop NMSC at a young age," said Professor Sinclair.

The researchers collected hospital admission and death data from the All England Record-linked Hospital between 1999 and 2011, and constructed two cohorts: a cohort of 502,490 people with a history of NMSC, and a cohort of 8,787,513 people who served as controls.

They followed up with the participants electronically for five to six years, and 67,148 from the NMSC cohort and 863,441 from the control cohort subsequently developed cancers.

They found that for those who had NMSC, the relative risk for developing cancers of the bladder, brain, breast, colon, liver, lung, pancreas, prostate, and stomach remained consistently elevated for the entire period of the study, and the risk for cancers of the brain, colon, and prostate increased with time.

The researchers also found that those who had NMSC under 25 years of age were 53 times more likely to get bone cancer, 26 times more likely to get blood cancers, 20 times more likely to get brain cancer, and 14 times more likely to get any cancer excluding those of the skin.

"The risk increases for a large group of seemingly unrelated cancers; however, the greatest risk relates to other cancers induced by sunlight, such as melanoma."

"Early detection of cancers through screening of asymptomatic people works best when screening can be targeted at those at greatest risk. Our study identifies people diagnosed with NMSC at a young age as being at increased risk for cancer and, therefore, as a group who could benefit from screening for internal malignancy," Professor Sinclair said.