Deaths from breast cancer have fallen by one fifth in the North while mortality from the disease in the Republic has remained constant over the last decade, according to a major report to be published today.
The report attributes this difference, in part, to the lack of a full breast screening programme in the Republic.
The all-Ireland cancer statistics second report, a collaboration between the Northern Ireland Cancer Registry (NICR) and the Republic's National Cancer Registry (NCR), will show there are 2,715 new cases of breast cancer on the island each year; 923 women die from the cancer annually, making it the leading cause of cancer and of cancer-related death. Some 50 per cent of cases are under 58 years of age at diagnosis.
Although the incidence of breast cancer on the island is increasing at a rate of 1.5 per cent per year, death from the disease is falling at a rate of 4 per cent per annum in the North. There has been no reduction in breast cancer deaths in the Republic, however.
In a commentary on these differences the report states: "Established screening programmes in Northern Ireland and the lack of such programmes until recently in the Republic of Ireland may have contributed to the regional differences observed."
Asked to comment on the 20 per cent reduction in breast cancer deaths in the North since 1994, Dr Anna Gavin, director of the NICR, said: "In the North, since 1993, we have had a full decade of breast screening which has helped to reduce breast cancer deaths markedly here.
"I would expect to see a similar fall in the Republic when breast screening is fully rolled out in the South."
Breastcheck, the Republic's national breast cancer screening programme, began screening in 2000, but is currently available only to women between the ages of 50 and 64 living in the eastern half of the State.
The Minister for Health, Mr Martin, is committed to extending the programme throughout the State, with plans to open screening clinics in Cork and Galway to complement those already operating in north and south Dublin.
Commenting on the regional differences, Dr Harry Comber, the director of the National Cancer Registry in the Republic, said: "There are a number of different phenomena at work which explain the differences in breast, lung and colorectal cancer rates."
He said the high rates of breast cancer found in Dublin and Kildare may reflect the greater availability of mammography in the area.
The North-South report notes that Ireland compares poorly with other EU states. The incidence of breast cancer for the island is 10 per cent higher than the EU average. Death rates from breast tumours are 15 per cent higher than the EU and 30 per cent higher than for women in the US.
"Why our incidence and mortality rates are higher than the EU is unclear," the report says. "Ireland's higher rates for the incidence and mortality may be due to our mix of established screening in Northern Ireland, and new or no services elsewhere. Patients' treatment decisions or their quality of care could also play a role, as could differences in behavioural risks or genetic susceptibility."
The report suggests that Ireland's significantly low survival rate for breast cancer may be due to more women being diagnosed with late stage disease, when treatments are less effective, because of a lack of screening.