People in Northern Ireland have a lower risk of developing some cancers than residents in the Republic, a major cross-border survey has revealed.
The study, carried out in electoral divisions over 12 years and prepared by the Cancer Registry at Queen's University Belfast, and the National Cancer Registry in Cork, involved 18 types of cancer.
Those which were significantly higher for both sexes in the Republic were non-melanoma skin cancer, melanoma, leukaemia, bladder, pancreas, and brain/central nervous system cancers.
The risk of prostate cancer for men, as well as cancer of the oesophagus and cervix for women, was higher in the Republic.
However the data showed lung cancer risk was higher in Northern Ireland, where the rate for uterus, non-Hodgkin's lymphoma, and head and neck cancers was also higher among women.
The first ever all-Ireland cancer atlas survey also revealed that lung, stomach, head and neck and cervical cancers were more common in areas of higher unemployment and low levels of degree attainment.
The findings were the same for non-melanoma skin cancer, female breast cancer, prostate cancer and melanoma.
Dr Anna Gavin, director of the Northern Ireland Cancer Registry, said the mapping of cancer geographically was hugely important in the quest to understand factors that increase cancer rates and also to provide appropriate treatment and cancer services.
She added: "While it is generally accepted that geographic variations in cancer risk are predominantly the result of factors such as tobacco smoking, alcohol drinking, obesity, diet and sexual behaviour there are also a number of findings which we cannot explain yet, including the band of increased stomach cancer incidence from Donegal to Dublin."
Dr Harry Comber, director of the National Cancer Registry, said the survey showed major variations, sometimes more than two-fold, in the risk of several cancers, across the island. "Understanding the reasons for this geographical variation, and taking appropriate action, would reduce the cancer burden significantly in Ireland," he said.