Dr. Gershon Ejeckam worked at the St. John's pathology lab from 2002 to 2006. (CBC)

A pathologist who identified serious problems in a St. John's laboratory has outlined for a public inquiry a litany of problems that he observed while he worked there.

Dr. Gershon Ejeckam wrote a memo in 2003 that has been referred to frequently at the Cameron inquiry, which is examining how the lab produced hundreds of inaccurate results for particular hormone receptor tests over an eight-year period.

Ejeckam, who flew to St. John's from Nigeria to testify, said he was troubled by the inconsistent results on tests of breast cancer tumor samples soon after he started working at the lab in 2002.

"The stains were not crisp enough, or they were not immediately interpretable," said Ejeckam.

"Sometimes, you know, you get a good stain today, and tomorrow the same block may not show the same thing. So we thought we needed to look at it and be sure what we're dealing with."

By April 2003, Ejeckam would write a memo outlining serious problems in the lab. While he appeared satisfied a month later, he wrote a followup memo in June that outlined a series of problems, ranging from what he called "grossly inadequate" staffing levels to a poor physical layout of the lab.

Ejeckam even warned his superiors that inaccurate lab results put the former St. John's Health Corp. — one of the authorities merged into Eastern Health in 2005 — at risk for lawsuits.

That warning, though, brought little reaction.

Inquiry co-counsel asked Ejeckam, who retired from Eastern Health in 2006, whether he took his concerns to executives at the health authority.

"I didn't think it was necessary," Ejeckam said. "I don't report to them directly, so I made my memo to the authorities looking after the laboratory.

"If they needed to go to the VP, it's their decision to make, not mine."

Several officials, including former chief executive officer George Tilley and former vice-president Dr. Robert Williams, have said they had not been aware of Ejeckam's concerns until the memo became public in 2007.

Ejeckam will return to the stand on Wednesday to outline in more detail some of the problems inside the pathology lab.

Eastern Health did not learn until the spring of 2005 that it had serious problems with estrogen receptor and progesterone receptor testing. The authority temporarily suspended its own tests while overhauling the lab, and sent samples to Mount Sinai Hospital in Toronto for retesting.