Joan Rivers' daughter, actress and television producer Melissa Rivers, has claimed her mother's death was "100% preventable". 47-year-old Melissa was a guest on the Today show on Monday (24th May). Whilst appearing on the show, Melissa revealed there were aspects of Joan's hospital treatment which she felt contributed to her mother's "preventable" death.

Melissa and Joan RiversMelissa Rivers (L) with her mother Joan Rivers, photographed together in 2013.

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Joan died in September 2014 at the age of 81. The comedienne was undergoing throat surgery at a Manhattan clinic, Yorkville Endoscopy, when she stopped breathing. She was rushed to hospital and immediately placed in a medically induced coma but she died a week later. Melissa revealed details of her terrible experience seeing her mother in the hospital and in a coma during the interview. 

"I couldn't believe what I was seeing. It becomes very surreal and there's my mum and machines and doctors and I think at that point it started to dawn on me a little the craziness that would ensue," Melissa said.

Read More: Melissa Rivers To Release The Book of Joan: Tales of Mirth, Mischief And Manipulation Honouring Late Mother.

Melissa filed a malpractice lawsuit against the clinic where Rivers stopped breathing in January and the legal proceedings are ongoing. Melissa, in this latest interview, once again restated her claim that there were serious failings with the clinic. Although what initially happened to Joan was an accident, the constant failings were a factor in Joan's death, Melissa argued. These failings included the clinic's staff allegedly taking photographs of themselves and Joan during her surgery, not paying attention to vital signs and providing a properly equipped crash cart.

"Yes, it was a tragic accident," Melisa said. "If something happens, and everyone does everything properly, things happen. You live with it. When it's error after error, after error, after error, after behaviours that you cannot even begin to get your head around - you get mad."

Melissa was also on the show in order to promote her memoir, The Book of Joan: Tales of Mirth, Mischief and Manipulation, which primarily centres on her relationship with her late mother. The book is released worldwide on 5th May. 

Watch Melissa Rivers' Interview On The Today Show: