Political aide Darrell Hynes told the Cameron inquiry he was led to believe in November 2006 that there was an error rate of three per cent with breast cancer tests. (CBC)

An aide to a former minister of health has told Newfoundland and Labrador's breast cancer inquiry that Eastern Health officials played down the rate of error of hormone receptor tests during a key meeting.

Darrell Hynes, who served as policy adviser to former health minister Tom Osborne, also told the Cameron inquiry that he failed to read important documents that showed that Eastern Health withheld important information about cancer testing errors — information that the government expected would be released in December 2006.

Hynes told Justice Margaret Cameron that he and Osborne met with former Eastern Health chief executive officer George Tilley and Susan Bonnell, the health authority's director of strategic communications, in November 2006, as Eastern Health prepared to disclose publicly the results of a massive retesting effort of hormone receptor tests.

Hynes said Tilley and Bonnell broke down the numbers for Osborne, focusing on the number of living patients who could benefit from a change in treatment.

"I'm seeing this information for the first time," said Hynes, describing how he tried to keep up with an interpretation involving approximately 100 cases out of 2,800 hormone receptor tests.

Hynes said he was led to believe during that meeting that the error rate of the hormone receptor tests — which help determine whether a breast cancer patient can benefit from the potentially lifesaving treatment Tamoxifen — was only three per cent.

"I'm writing it down, I'm trying to follow the conversation and I'm writing down what I'm told," Hynes told Justice Margaret Cameron.

"I don't remember, you know, doing the math in my head to figure out if that was the correct number, but the three per cent was … factually told to me, so I recorded it."

Hynes said he and Osborne were told the errors were well within an acceptable range.

Error rate several times higher than disclosed

During a media briefing weeks later, Eastern Health officials said they could not for legal reasons release all the data about the results of a massive retesting program, but the authority said the error rate could be as low as 10 per cent.

However, Eastern Health revealed in an affidavit filed in 2007 with Newfoundland Supreme Court for a since-certified class-action lawsuit that 42 per cent of the estrogen receptor and progesterone receptor tests sent for retesting were wrong.

Hynes had some experience with the issue, having previously been executive assistant to former health minister John Ottenheimer, and testified Wednesday that he was shocked to have learned in 2005 that some breast cancer patients, who later died, could have benefited from Tamoxifen.

Meanwhile, Hynes shed more light for the inquiry on how Eastern Health's decision to withhold information at the December 2006 media briefing passed by government without any notice.

Osborne has already testified that he did not catch media reports from that day, and media summaries prepared for him did not mention a discrepancy between what he had been told in November and what Eastern Health told journalists.

As well, departmental communications director Tansy Mundon testified earlier this week that she did not realize anything had been withheld, even though several media reports highlighted the fact Eastern Health was not releasing all the data it had.

'Water on the beans has changed'

Hynes said Eastern Health sent "a fairly lengthy package of materials" that he printed and put in a file to read later.

However, Hynes said he was busy, and did not review the material until he prepared for his testimony at the inquiry. He said he was disturbed by what he had missed.

"There [were] no numbers," he said. "There was some wishy-washy answer about we're not going to get into a numbers game or something to that effect, but … they never released this information, as we expected."

Hynes said that had he been aware of that, he definitely would have "immediately" alerted Osborne.

"I would have given him strong advice that this is not what we were told three weeks ago ... that the water on the beans has changed [and that] this is not what we thought."

Osborne testified this spring that he was not aware of Eastern Health's decision, and was infuriated to learn in May 2007 that Eastern Health had even withheld important data from him during the confidential briefing in November 2006.

Cameron's inquiry is examining what went wrong with hundreds of hormone receptor tests between 1997 and 2005. She began hearing evidence in March.

The inquiry's focus has largely been on the response of Eastern Health and government officials to revelations of testing problems.

Next week, key evidence is expected on problems inside the pathology lab.