According to The Associated Press, the ABC morning show anchor is temporarily leaving the show to undergo a bone marrow transplant to treat MDS or myelodsyplastic syndrome -- a blood and bone marrow disease she was diagnosed with earlier this year.
During her absence, Roberts, 51, said some of her "wonderful" friends like Barbara Walters, Diane Sawyer and Katie Couric will serve as a guest host.
At the Television Critics Association conference in Beverly Hills on Thursday, Roberts said, "It’s fascinating-slash-scary how to prepare yourself for something like this."
While she did admit, "I do go through moments of fatigue," Roberts added that GMA's big ratings has kept her in good spirits. "The run that we've had has truly energized me," she said. "It's pretty good medicine, I gotta say, to be taking!"
Five years after she battled breast cancer, Roberts announced to her GMA viewers she was diagnosed with MDS on June 11. "My doctors tell me I'm going to beat this -- and I know it's true," Roberts wrote on GMA's website. "They say I'm younger and fitter than most people who confront this disease and will be cured."