A petition, signed by 40,000 people, calling for the provision of a radiotherapy unit for cancer patients in the south-east is to be presented to the Taoiseach, Mr Ahern, when he visits Waterford on Friday.
Campaigners for the unit also plan to stage a "silent protest" outside Waterford Institute of Technology, where Mr Ahern has an engagement on Friday morning.
The South Eastern Cancer Foundation, which is organising the protest, intends to exploit the fact that the Taoiseach's visit is taking place on daffodil day, the Irish Cancer Society's national fundraising day.
Members of the public are being invited to attend the demonstration, which takes place at 10.30 a.m., and to carry a daffodil.
In a letter to Mr Ahern, the chairwoman of the foundation, Ms Maggs Kirwan, said the need for a radiotherapy unit in the south-east was urgent.
"We, the people of the south-east, need and deserve a quality cancer service that will allow us to avail of the 'best practice'. We hope that you will give a personal commitment to pursuing the earliest provision of this much-needed unit," she said.
The foundation hopes the Taoiseach will meet them on Friday. It will present the petition with more than 40,000 signatures collected throughout the region over the past three weeks.
The lack of a radiotherapy unit in the south-east is set to be a major election issue. About half of the 1,000 cancer patients diagnosed in the region each year require radiotherapy. Many do not get the treatment because demand far outstrips supply, and those who do face waits of up to 10 weeks before receiving radiotherapy at St Luke's Hospital in Dublin.
Patients from the south-east who gain admission to St Luke's face a choice of spending five weeks away from home or travelling 200-mile round journeys each day for treatment which lasts just a few minutes.