In what officials are calling a "tragic medical error," a surgical team removed the wrong kidney from a patient with kidney cancer last week at Methodist Hospital in St. Louis Park, the hospital disclosed Monday.

Officials said the error occurred weeks before the surgery, when the kidney on the wrong side was identified on the patient's medical charts as cancerous. The patient, who was not identified, was left with the cancerous kidney when the healthy one was removed.

"We feel just profoundly responsible for this," said Dr. Samuel Carlson, chief medical officer for Park Nicollet Health Services, which owns Methodist Hospital.

Hospital officials said that they apologized to the patient and family, and "are working closely with them to support them in every way we can."

The hospital took the unusual step of announcing the mistake in a memo to Park Nicollet employees on Monday. "An error of this degree has, to the best of our knowledge, never happened at this hospital before," Carlson said.

Officials would not discuss what effect it may have on the patient's chances of recovery.

They said the family has asked for privacy, that "the patient has chosen to remain at Methodist Hospital" and that all treatment options are being discussed.

"This is a devastating tragedy for the family," officials said in Monday's staff memo. "It is also a tragedy for all of us at Park Nicollet."

They said the surgeon in this case has voluntarily stopped seeing patients until the hospital completes its inquiry of how the mistake occurred.

Statewide, a total of 24 wrong-site surgeries were reported to the Minnesota Department of Health between October 2006 and October 2007.

Two of those errors were at Methodist, but Carlson said they were relatively minor in comparison to last week's error: a needle biopsy on the wrong lung, and a diagnostic exam of the wrong bronchial tube.

He said they decided to go public in this case because of its unusual nature and severity. This time, he said, the mistake was "certainly more severe and more significant."

Kathleen Harder, a University of Minnesota researcher who studies medical errors, said mistakes of this magnitude are rare but do happen.

"They remove the wrong ovary, take off the wrong leg," she said. Many hospitals have stepped up efforts to catch errors in the operating room. But as in this case, she noted, the problem can occur long before the operation begins. "It's wrong in the chart ... and that sets it up for a train wreck."

Nationally, wrong site surgeries are proving difficult to eliminate, according to the Health Department's annual report on medical errors.

In December, the Minnesota Hospital Association started a statewide campaign to try to reduce the number of wrong-site surgeries, with such things as safety checklists and routines for marking surgical sites. Some 90 hospitals agreed to adopt those procedures.

Methodist said those procedures were used in this case. But the day after surgery, a hospital pathologist reported that the kidney that had been removed had no evidence of cancer.

Hospital officials would not talk about the next steps for this patient. But Carlson, speaking generally, said that the options would depend on individual circumstances, such as "where the cancer in the kidney was located," and whether only that part could be removed. Asked about the possibility of a kidney transplant, he said that would depend on a patient's condition, as well. In some cases, he noted, a history of cancer could make someone ineligible for a transplant.

Ultimately, the decision will be up to the patient and the patient's family.

"As you can imagine, currently they are needing a lot of support and understanding," he said, "and we're doing our very best to provide them with that."

Josephine Marcotty • 612-673-7394 • Maura Lerner • 612-673-7384 •