Newfoundland and Labrador Premier Danny Williams lashed out Monday at the province's largest health authority, accusing Eastern Health of downplaying revelations that it had missed dozens of breast cancer patients in a massive retesting exercise.

Eastern Health, meanwhile, on Monday disclosed that it had somehow missed 43 patients, up from the 38 patients the authority had revealed late Friday afternoon in a news release.

"It's disgraceful. They should be shot over there," Williams told reporters outside the legislature, attacking how Eastern Health had released information about the cancer patients whose hormone receptor tests now have to be retested.

Eastern Health issued the news in a statement late Friday afternoon, albeit under a headline that said it was updating the public on implementation of Cameron inquiry recommendations. The disclosure that patients had been missed did not appear until midway in the statement.

"They've learned absolutely nothing," said Williams.

Justice Margaret Cameron, in a report released last month, found that Eastern Health had erred by not telling the whole truth of what it knew, Williams said. The premier slammed the authority for sending out information late on a Friday and then not making anyone available to talk about it immediately. He said patients deserve full and transparent disclosure.

"This is about people's lives … They have a right to be told," Williams said. "They have a right to be told in a proper manner. There has to be proper disclosure; there has to be someone there to answer questions. It's not something you do at the tail end of a Friday afternoon."

Williams had earlier told the legislature that changes are needed at Eastern Health and that he has asked Health Minister Ross Wiseman to "get to the bottom" of the problem.

"Something like this is unnecessary and unacceptable," said Williams, who added that cabinet was briefed on the missed patients on Thursday and had asked for quick disclosure. "Something has go to happen. Something has to change."

Hours before Williams made his comments, Eastern Health's chief operating officer, Pat Pilgrim, told reporters in St. John's that the count of patients who had been missed might increase yet again, as a file-by-file review continues.

"To our patients, we know how distressful this is to them, to be hearing from us now, almost four years later, that we missed you," Pilgrim said.

"We apologize to our patients for that. We wish that we could undo that," said Pilgrim.

Peter Dawe, executive director of the Newfoundland and Labrador division of the Canadian Cancer Society, said the latest disclosure is extremely upsetting for patients, particularly after a cascade of revelations at the Cameron inquiry.

"I have no confidence whatsoever that there will ever be a final number with this whole fiasco," Dawe told reporters immediately after the Eastern Health briefing.

Of the 43 patients, at least 27 are now deceased. It's not known whether a different treatment would have affected any of the patients.

Additionally, 12 other patients do not require a change in treatment. Four patients may require a change in a treatment.

Eastern Health was the subject of a gruelling examination at the Cameron inquiry, which reported last month on how 386 patients had been given inaccurate results. It's not yet known how many of those missed patients were given wrong results, as the retesting process is now underway.

Pilgrim responded to criticism that Eastern Health has mishandled its patient notification process.

"[We are] working hard to find any appropriate balance between disclosing information directly to our patients, which is our first priority, while also informing the public of as much detail as we can, in a timely manner," Pilgrim said.

"This is a very delicate balance."