Some Otago doctors say their patients may have an increased risk of early death from bowel cancer because they are being refused colonoscopies at Dunedin Hospital.
They say some patients denied diagnostic colonoscopies, even when they had all the accepted signs of possible bowel cancer, have later been found to have the disease.
Mr Ryall said there had been issues with colonoscopy services in Dunedin for at least a couple of years, but the situation "sounds very concerning".
His request for an urgent report included asking the board "what they are doing about it".
His office advised he would be expecting answers in days rather than weeks.
Prof Murray Tilyard, executive director of South Link Health, which represents about 500 GPs throughout the South Island, said this week he had been asked by doctors to survey Otago GPs to see if their increasing concerns were isolated incidents or more widespread.
In July, he asked them to report instances of delays or lack of access to Otago District Health Board colonoscopy services.
The Otago Daily Times sought his comments after it received a copy of a letter dated October 14 Prof Tilyard sent to board chief executive Brian Rousseau and to 175 Otago GPs.
The letter said there was a significant issue with access to colonoscopy for patients with possible bowel cancer symptoms and some had poor outcomes - including premature death - because of late diagnosis.
"General practice regards the issue of access to colonoscopy in Otago as a serious concern which appears to potentially be putting patients at risk," the letter stated.
Some doctors say they are advising patients who can afford it to seek private colonoscopies at a cost of about $1000 - work they say is sometimes carried out by the same staff involved with decisions to deny access in the public hospital when patients have not met the board's assessment criteria.
The letter showed 26 GPs replied to Prof Tilyard's survey with concerns covering access for 51 patients - both men and women - aged 30 to 92.
Mr Rousseau said yesterday it would be irresponsible of him to comment on the cases raised by the doctors until the board had investigated.
He had received a list, which appeared to be the same one as in the October 14 letter, on October 6 and had emailed Prof Tilyard within half an hour of its receipt seeking the National Health Index numbers of patients so the investigation could proceed.
He had yet to receive the numbers and did not see he could have acted any more quickly.
Mr Rousseau said he considered the matter urgent.
"It's absolutely critical we get those numbers so we can in fact follow up."
Prof Tilyard had approached him during September about the issue and on September 29 he had reminded Prof Tilyard about providing further information.
Until the investigation was completed it would be "highly irresponsible" to suggest the service was not performing, he said, adding the status of the survey information remained anecdotal until it could be checked.
At this stage, the board did not know if the patients had "even been referred", he said.
He agreed it was an unusual letter for the board to receive; those involved clearly raised a concern.
Board chairman Errol Millar said it was not appropriate for him to comment before the investigation was completed because it could be "shying at shadows".
He was confident Mr Rousseau had acted promptly once the matter was brought to his attention.
Prof Tilyard said he could not recall Mr Rousseau's October 6 email, but he had been away from work some days due to illness.
He did not wish to argue about the timing issues.
The issues being raised by the doctors had been going on for a number of years, he said.
It was important that doctors provided the NHI numbers promptly.
Of the cases reported in the survey, 42 patients were listed as having been refused a colonoscopy, sometimes more than once.
Thirty-four had one or more symptoms of possible bowel cancer, the doctors said.
Of those who were refused a colonoscopy, 25 were later found to have cancer.
Nine of those were diagnosed privately.
Three patients went to the emergency department with bowel obstruction.
In instances where patients had received colonoscopies, doctors noted delays they found unacceptable.
In one case, a patient initially declined a colonoscopy could not have one when approved seven months later because of the severity of the tumour, a doctor noted.
In 31 of the 51 patients where doctors listed access concerns, they said patients were later found to have bowel or rectal cancer.
Some patients in the survey later died of bowel cancer, but the information provided about the cases in the letter to the board does not always state the stage of the cancers when found. .
In response to questions from the Otago Daily Times about survival rates, senior lecturer in the University of Otago department of medical and surgical sciences Dr Chris Jackson, an oncologist, said by the time patients showed symptoms of bowel cancer, their cancers could have already advanced beyond the first stage at which the prognosis for long-term survival was highest.
Colon cancers generally grew over a period of about four to seven years and it was not known if a delay of three months in diagnosis would change a stage one cancer to a stage two one.
Stage one cancers were not likely to exhibit any symptoms - these were likely at stages two to four.
He agreed that a patient who presented as an emergency with an obstructed bowel had a risk factor for a worse outcome.
One doctor who took part in South Link Health's survey reported referring all cases privately or to surgeons for three years because of the lack of access to public colonoscopy.
While most of the doctors in the survey referred to concerns about patients with bowel cancer symptoms, some also questioned the refusal or delay of surveillance colonoscopies for people previously treated for bowel cancer or who had a strong family history of the illness.
The board altered its rules about routine screening of people with close family members who have had bowel cancer in September 2007 because it could not meet the demand for diagnostic tests.
It was noted at that time that along with at least two other hospitals it was not able to offer screening in accordance with national guidelines.
The survey did not ask doctors to confine their concerns to a particular time, but Prof Tilyard said he believed the situation had been bad in the past two or three years.
Prof Tilyard said he regarded the survey response, which had included a further six GPs who did not report any specific problems, as "pretty good".
"It shows you there's real concern."
Nobody would know if it was the tip of the iceberg unless there was an audit of all referrals to the colonoscopy clinic, he said.
Prof Tilyard's letter stated he was aware one of the issues for the board when deciding who should go forward was the appropriateness and adequacy of information provided.
Questioned on this, he said he had not seen the specific referrals from the doctors, but would have expected them to have recorded their concerns about their patients' symptoms.
Prof Tilyard said he knew the board had to make hard decisions because it did not have the resources for everything, but "you either have a service or you don't".
While Prof Tilyard's October 14 letter did not name the doctors who contributed to the survey, it said that he had discussed the survey with board oncologist Dr Shaun Costello, who indicated he wished to review the referral letters, assessment process and outcome.
In the letter, Prof Tilyard advised Mr Rousseau he would be contacting the doctors who participated to provide the relevant patients' NHI numbers so Dr Costello could carry out this work.
