Groundbreaking comedienne Joan Rivers is on life support, according to TMZ: "[S]ources close to the legendary comedian tell TMZ she is completely reliant on machines to stay alive."

Rivers has been hospitalized at Mount Sinai since last Thursday, after going into cardiac arrest during an endoscopic procedure. She was stabilized and placed into a medically-induced coma afterwards. Her daughter Melissa Rivers said last week, "I want to thank everyone for the overwhelming love and support for my mother. She is resting comfortably and is with our family. We ask that you continue to keep her in your thoughts and prayers."

TMZ reports, "According to our sources, the family will have to decide in the next couple of days whether to keep the 81-year-old on life support. We're told the family remains hopeful that if they do decide to turn off the machines, she will make a turn for the better and fight through it."

The Daily News' sources say that Melissa Rivers is "'in denial' over her mother’s condition."

“She still thinks everything is going to be OK. She is refusing to admit that a world might exist without her mother in it,” said a source close to the Rivers family.

“Others that are close to Joan are starting to realize that the outcome they want is very unlikely.”...

Sources have told The News that Rivers would not want to live unless she could enjoy “a full and active life....(She) would never want to be a burden on anyone.”

Rivers had been performing the night before being hospitalized—she told the audience, "I’m 81 — I could go at any moment."