NEW YORK (CBSNewYork) -- Melissa Rivers plans to sue the doctor who performed an unscheduled biopsy on her mother.
Joan Rivers, 81, went into cardiac arrest at Yorkville Endoscopy Aug. 28 following a minor, elective vocal cord procedure.
She died a week later at Mount Sinai Hospital surrounded by family and close friends. The clinic is under investigation by the state's health department, and its medical director, Dr. Lawrence Cohen, is no longer performing procedures at Yorkville Endoscopy.
According to reports, Joan's own personal doctor performed an unplanned biopsy after another doctor at Yorkville Endoscopy noticed something on Rivers' vocal cords.
The comedian's vocal cords seized, a condition called laryngospasm, and cut off her air supply, according to reports.
Rivers' personal doctor also snapped a selfie with her while she was under anesthesia before performing the unauthorized biopsy, a source told CNN.
Stars, family and friends attended Rivers' Upper East Side funeral Sept. 7 at Temple Emanu-El.
Howard Stern delivered the eulogy, Broadway singer-actress Audra McDonald sang "Smile" and bagpipers played "New York, New York."
The lights on the Great White Way were dimmed for Rivers two days later.
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