The former head pathologist at Eastern Health, who was in charge when hundreds of testing mistakes were discovered, told the Cameron Inquiry Thursday that he noticed sample quality problems in the spring of 2005.

Dr. Donald Cook continued his testimony at the inquiry into faulty hormone receptor tests Thursday in St. John's.

Cook testified that an oncologist reported to him in May 2005, that a breast cancer patient had been given one result on a test to determine which treatment she should receive, but after her test was redone, she received a different result.

"I asked her were there any other concerns that she had about any other patients and she said there were three or four she had concerns about," Cook said.

He told the inquiry that he then met with a group of oncologists and lab managers to discuss the problem. The group decided to redo a couple of dozen tests to see what would happen to the results.

Cook said most of the results changed on retesting.

On Thursday, Cook testified that a new testing system, called Ventana, had been in place in the lab for more than a year at that point. When the testing slides, which contained the breast cancer tissue, from the Ventana system and from the older equipment were compared, Cook said he spotted a difference in quality immediately.

"Overall, the quality I felt was not as good as the Ventana system was producing," Cook said of the older samples. "There was, I would say, many instances where the slides were folded, a lot of bubbling on the slides. So, overall the quality issue was there."

In external reviews of the lab performance, equipment was ruled out as a cause of poor quality of samples. Those same reviews found that lab technicians were lacking in training and tissue samples were not properly being processed.

Memos didn't alarm

Eastern Health has maintained it was not aware of problems at the lab until 2005, when samples were sent to Mount Sinai Hospital in Toronto for retesting.

However, a June 2003 memo written by former pathologist Gershon Ejeckam lays out a litany of problems with the lab, from "grossly inadequate" staffing to "persistent [and] erratic results of immunostains."

Ejeckam, who retired in 2006, wrote that the lab was doing tests in a location without proper humidity controls, which might affect results.

He also warned about an ever-increasing workload, inadequate relief staffing and concerns about obtaining "reliable, reproducible and consistent results" with samples.

Ejeckam, whose memo identified lab problems that extended beyond hormone receptor tests, clearly flagged the risks of not dealing seriously with quality issues.

Cook testified Thursday that he had no indication in 2003 that there were problems in the lab that would affect patient care.

He testified that he had seen three memos from Ejeckam in spring 2003, but didn't act until the third — which he considered to be the most startling. Cook said he got assurances from a lab administrator that the problems raised by Ejeckam's memos were being addressed.

External reviewers investigated Eastern Health's laboratories in 2005 and 2006 after the authority found some of the tests it had done for breast cancer patients were inaccurate.

Cook is on sick leave from his position as site chief of pathology with St. Clare's hospital in St. John's.