WINNIPEG - Three people with prostate cancer may have missed receiving radiation treatment based on tests from a Manitoba pathologist whose work is under review.

The three cases were revealed Wednesday as the Winnipeg Regional Health Authority announced that 14 additional cases are being scrutinized as part of a wider investigation into more than 700 tests handled by a longtime pathologist.

"Because our review is still ongoing, we don't have the complete picture, and understandably that creates anxiety in members of the public," Dr. Brock Wright, chief medical officer for the Winnipeg Regional Health Authority, said Wednesday.

"What we've learned so far is not as alarming as I believe many people in the public fear."

Last Friday, the health authority announced that a pathologist who handles tissue samples for six Winnipeg hospitals and a number of doctor's clinics was put on leave because of errors found during a routine quality control.

As of Wednesday, 324 cases had been re-evaluated, with discrepancies confirmed in three prostate cancer cases. Another 14 cancer tests are flagged for further review, bringing to 17 the number of cases that could affect patients' treatment or diagnosis.

The health authority would not say what types of cancer are involved.

While the review is short of the halfway mark, Wright said there have been some encouraging signs.

"We're not satisfied right now to the point where we're comfortable stopping the review," he said.

"What's reassuring, though, is that there are a large number of cases... where the report was accurate."

For the three prostate cancer patients with discrepancies in their tests, the question is whether they should have received radiotherapy in addition to surgery to remove tumorous prostate glands.

The three patients were contacted and were offered appointments with their doctors the next day. All were promised "expedited" treatment if required, Wright said.

More than 150 people have contacted the health agency over concerns about their cancer tests.

All of them are receiving callbacks and their files are being reviewed as appropriate.

Health officials won't say who the pathologist is and where he worked pending a more detailed investigation into what the errors mean for cancer patients.

Wright said the health authority does not want to send a negative message to pathologists by revealing the identity of pathologists whose work is under review.

"They'll clam up and not bring concerns forward," Wright said.

Last week, a hospital in Owen Sound, Ont., announced it had a high rate of error in about 600 tests performed by one pathologist.

A similar probe of 24,000 cases is also underway in New Brunswick, and a highly publicized review in Newfoundland found more than 300 people received incorrect breast cancer results between 1997 and 2005.