The Southern Cancer Network has been carrying out an independent audit of about 32 patient referrals which was originally due for completion at the end of November.
Some concerns raised by general practitioners included cases where they said patients who had all the accepted signs of bowel cancer had been denied the diagnostic test, only later to be found to have the disease.
Health Minister Tony Ryall, in an email response to questions about the report's delay to mid-February, said he had been advised there had been a significant problem in getting some required information and he was also told "there's been a difference of clinical interpretation between some of the clinicians involved".
There was no dispute over the fact the board had provided comparatively fewer colonoscopies than the rest of the country for "quite some years" and that needed to be dealt with, he said.
He was assured the board was planning to remedy this long-standing issue.
Board chief executive Brian Rousseau yesterday confirmed the board would be increasing the number of colonoscopies it had originally planned to do this financial year.
Accurate numbers and projections were not available yesterday, but chief operating officer Vivian Blake said it looked as if the hospital was already ahead of its contracted volumes.
The board had previously expected to complete about the same number of colonoscopies as it had managed to last year, which was 557.
Mr Rousseau said he could not comment on the clinical differences referred to by Mr Ryall as this was part of the due diligence process of getting the report finalised.
In mid-October, Mr Ryall called for an urgent report into the situation after the GPs' concerns, which had been aired in an informal survey conducted by South Link Health, became public.
In the survey, concerns were raised more than about 50 patients, some of whom GPs said had been denied surveillance colonoscopies, but only about 32 of them proceeded to be processed by the audit team.
Mr Ryall said this week he knew the community was frustrated by the delays and so was he, but he would rather wait to get a report that "gets it right than have one that is incomplete".
The survey had been delayed from the end of November to mid-December and then it was expected this month.
Acting chief executive of the Southern Cancer Network David Meates advised earlier in the week the delays had been due to the complexity of accessing the patient information combined with the time required to ensure the district health board feedback was fully taken into consideration.
Questions seeking more detail on the process were not answered by Mr Meates yesterday.
The audit reviewers have held separate meetings with Mr Rousseau and board clinicians.
South Link Health executive director Prof Murray Tilyard could not be contacted for comment yesterday.
