Updated

A Minnesota surgeon has agreed to stop seeing patients after he made an "unthinkable" mistake — he removed a healthy kidney, leaving the cancerous one inside a patient, KARE 11 TV reports.

"This has been a tragic event and Park Nicollet has accepted full responsibility," said Dr. Samuel Carlson, chief medical officer for Park Nicollet Health Services.

Carlson declined to name the surgeon who performed the procedure.

Although the surgery was performed last Tuesday, it wasn’t until the next day that pathology reports confirmed the wrong kidney had been taken from the patient, whose identity is not being revealed due to patient confidentiality.

Carlson said standard protocols were followed in the Methodist Hospital operating room to prevent such an occurrence, but new safety protocols have been added. Surgeons now will have to double-check MRIs and CAT scans before starting surgeries, he told the TV station.

Carlson would not comment on the patient’s prognosis, age or gender.

The patient still was receiving care at Methodist Hospital, Carlson said.

Click here to read more on this story at KARE11.com.

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