Melissa Rivers Says Joan Rivers's Death 'Was 100 Percent Preventable'

In her first formal interview since her mother's death, Melissa Rivers tell Today's Matt Lauer that Joan Rivers's death "was 100 percent preventable."

Today has only released a short clip from the interview, which airs in full on Monday morning. In it, Rivers talks about the malpractice suit she's filed against Yorkvile Endoscopy, the clinic where Joan went in for a routine surgery in August 2014 from which she would never wake up. Rivers claims the clinic could have taken any number of steps to prevent her mother's death.

"How about paying attention to the vital signs," Rivers tells Lauer. "How about having a properly equipped crash cart?"

Related: Joan Rivers Leaves Money to Several Worthy Causes in Her Will

In the initial malpractice suit filing in January, Rivers's lawyer claimed that the doctors performing Rivers's endoscopy failed to recognize she wasn't getting enough oxygen, which ultimately led to her death. The suit also claims the doctors performed an unplanned biopsy and, most shockingly, took selfies with Rivers while she was under anesthesia.

In a federal investigation, the Centers for Medicare and Medicaid found that Yorkville Endoscopy made several errors, and threatened to revoke the clinic's accreditation unless it cleaned up its act by March 2. Yahoo made a call to the clinic Friday morning and though they had no comment on Rivers's claims, they were still open.

Related: Melissa Rivers Tearfully Accepts Posthumous Grammy for Joan Rivers

In memory of her glass-ceiling-shattering mother, Melissa Rivers has written a book, The Book of Joan: Tales of Mirth, Mischief, and Manipulation, due out May 5.