The Otago District Health Board is changing some of its practices after a critical report on access to colonoscopies and diagnostic procedures for bowel cancer at Dunedin Hospital.
The DHB says it will perform an extra 200 colonoscopies this year and in 2011.
A review of 33 cases that Otago GPs highlighted as potentially worrying found some patients waited more than two years for the tests.
The Southern Cancer Network review looked at 33 patients, 23 of whom were later determined to have either colon or rectal cancer.
The review says many patients had prolonged journeys through the system, with some waiting more than two years for diagnosis. However, the review does not make any findings about whether they suffered worse outcomes as a result.
The DHB has announced it has received Ministry of Health funding to increase the number of colonoscopies it performs each year from 500 to 700 and also plans to improve its patient referral systems.
Health Minister Tony Ryall says the ministry will work with the board to ensure it is prioritising colonoscopies fairly.