Robin is 51. But her age, her health and her sister will all play a key role in helping her battle this disorder.
"I have always been a fighter," she said on this morning's broadcast.
Robin Roberts announced this morning she is facing another medical battle, this time against myelodysplastic syndrome or MDS.
It is a rare disorder of the bone marrow, which produces red blood cells.
MDS can affect red blood cells, white blood cells and platelets.
It can cause fatigue, persistent infections and bruising or bleeding. It can also progress to acute leukemia. Roberts got blood tests after feeling more fatigued than usual.
Robin beat breast cancer five years ago. Chemotherapy and radiation increased her odds for MDS. But even so, it is rare.
Dr. Margaret Kasner of the Kimmel Cancer Center at Jefferson University Hospital says, "Huge numbers of women undergo therapy for breast cancer and the number of women who go on to get MDS or acute leukemia is relatively small."
Dr. Kasnerl says the only cure is a bone marrow transplant.
Robin's sister is a perfect match, which is also rare but very fortunate.
Dr. Kasner says with bone marrow transplants, the patient's own bone marrow cells are wiped out, then replaced with healthy cells from a donor.That should restore blood cell growth, and also immunity.
"So when you get someone else's immune system it will recognize cancer cells and get rid of them," she says.
She says it doesn't always work, but the younger someone is. and the closer the match, the better the chances of success.
And being the strong woman she is, Robin is optimistic.
She told her GMA colleagues, "And to use your phrase George, bottom line, I am going to beat this and my doctors say it to me and my faith says it to me."
Dr. Kasner says typically a bone marrow transplant takes about a month in the hospital, with pre-treatment and then recovery.
After that, even if it works, a person's immune system is still suppressed so they can be at risk for infection. Some get through that period quickly, while for others it can take several months.