The new three-year contract will start in June next year and is scheduled to run until the end of May 2010.
The brief includes the organisation's breast, cervical, bowel and prostate cancer screening campaigns.
The appointed agency will run a press office for the screening team, provide media training and parliamentary monitoring, and issue press releases. It will also be responsible for updating the Cancer Screening Office's website.
The agency will also advise on crisis management.
Beating Bowel Cancer recently accused the NHS's Bowel Screening programme of ignoring the needs of 3,500 people who die annually, because free prostate screening is only available for 60 to 69-year-olds.
Trimedia declined to comment on its repitch intentions.