There has been a major increase in the number of cases of prostate cancer reported in the Republic in recent years, according to a report due to be published today.
The report from the National Cancer Registry shows reported cases of prostate cancer have almost doubled between 1994 and 2001, the latest year for which data is available.
It also states that the highest incidence of prostate cancer has been found in the southwest of the State.
Dr Harry Comber, director of the National Cancer Registry, said yesterday there was no way the increase from about 1,000 cases of prostate cancer in 1994 to 1,800 in 2001 could be described as a natural increase.
He believes the increase is due to more PSA (prostate-specific antigen) screening for the disease.
Prostate-specific antigen is a protein produced by the cells of the prostate gland. The PSA test measures the level of PSA in blood and the higher a man's PSA level, the more likely it is that cancer is present but a biopsy is required to confirm a cancer diagnosis.
Dr Comber said there was no consensus on a national PSA screening programme. Evidence suggested that for this type of cancer, picking it up earlier may not make a big difference to the patient, he said.
He confirmed an investigation would now take place into the incidence of and screening for prostate cancers, north and south.
"We see contrasts between us and Northern Ireland. They feel they have the same rate of PSA testing as us but we have more cases of prostate cancer. It may be we do more biopsies. We will have to look at that," he said.
Meanwhile, the report, Cancer in Ireland 1994-2001, also shows that the number of cancer cases are increasing by 2.3 per cent a year, from 19,290 in 1994 to 22,473 in 2001. There were an average of 20,523 cases of cancer reported every year over the period.
Although non-melanoma skin cancer is the commonest cancer, this cancer has only a minor health impact, and the commonest of the major cancers is colorectal (bowel) cancer, at 1,821 cases a year.
There is no national strategy for dealing with this type of cancer but the National Cancer Registry has begun a study into the economic impact of this type of cancer and the most cost effective way of dealing with it.
The report shows large geographical differences in the incidence of cancer. Many of the major cancers appeared to be more common in the east of the State, but there were important exceptions to this.
These included head and neck cancers - the reported incidence of which was 30 per cent higher in the west than the national average over the period studied.
Similarly, the reported incidence of lung cancer was 30 per cent above the national average in the Dublin and Kildare regions between 1994 and 2001.
The higher incidence of breast cancer reported in some regions would probably reflect the fact that the BreastCheck screening programme was active in some regions and not in others, Dr Comber said.
An Ireland/UK cancer atlas, due for publication next month, will put these geographical variations in a wider context.
The National Cancer Registry report has also found surgery rates for most major cancers were higher for patients living in the east of the State in the 1994-2001 period, as were rates of radiotherapy.
The fact that radiotherapy rates were higher in the east will be no surprise, given that radiotherapy treatment has only, in the past, been available in Dublin and Cork.
But the report shows radiotherapy and chemotherapy rates for most cancers are increasing, and these geographical differences are likely to become less, the cancer registry believes.
It intends to publish a comprehensive analysis of patterns of treatment and survival for the period 1999-2001 later in the year. This should show in detail the initial impact of the National Cancer Strategy on cancer treatment.