New radiotherapy centres for Dublin should be located at Beaumont and St James's hospitals, an international expert group has advised the Minister for Health, Ms Harney.
Confirming that she had received the recommendation in January, Ms Harney said she would make a decision on the matter "very soon".
Beaumont is now set to become a super-regional cancer centre serving north Dublin and parts of Leinster and Ulster.
Patients from south Dublin and parts of Leinster will receive radiotherapy, chemotherapy and surgery at St James's.
However, a number of leading cancer experts have expressed concern that the Minister may decide to add a number of provincial satellite centres for radiotherapy in addition to the backbone of services in Dublin, Cork and Galway.
They are also concerned that Ms Harney may, under a public-private partnership initiative, encourage the development of private radiotherapy facilities at other centres in Dublin and elsewhere as a means of providing additional treatment facilities in the short term.
A leading Dublin cancer specialist said the State was in danger of creating a fragmented network of small cancer treatment centres, each with limited resources.
"This is a defining moment. We have an opportunity here to build state-of-the-art facilities to provide 21st-century cancer care for our patients. That can only happen in large academic teaching hospitals where a full range of multidisciplinary specialists are available on site. If we fail to grasp this opportunity and instead settle for a 'Band-Aid' solution, patients will suffer."
The group's recommendation brings to an end a rigorous process which began with the publication of the Hollywood report on the development of cancer radiation services in the Republic in 2003.
It recommended the recruitment of additional radiation oncologists and at least a tripling of the number of linear accelerators (the machines that deliver radiotherapy).
Some five Dublin hospitals, including Tallaght, St Vincent's and the Mater, made detailed presentations to the expert group and were subsequently visited by it at the end of last year.
Ms Harney said last night her priority in making a final decision on radiotherapy facilities would be "to improve patients' clinical outcomes and experience of care. And I will want to see fast decisions followed by fast delivery".
Should she implement the decision of the international expert group, it will take a minimum of five years for the new Dublin cancer centres to open. In the meantime, St Luke's hospital will continue to provide radiotherapy services as it does at present.
Informed sources have suggested that Ms Harney may approve a link between St Luke's and the Beacon private hospital in Sandyford as a means of treating additional cancer patients in the short term.
This could be achieved by channelling public patients through the National Treatment Purchase Fund.