By Amanda Gardner
MONDAY, June 11 (HealthDay News) -- "Good Morning America" co-host Robin Roberts announced today that she is facing her second major health battle in just five years.
Roberts, 51, told viewers of the ABC show that she has been diagnosed with myelodysplastic syndrome (MDS), a rare blood disorder affecting the bone marrow and sometimes referred to as pre-leukemia.
"Myelodysplasia is a condition in which the bone marrow doesn't function properly," explained Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System in Baton Rouge, La.
Specifically, the bone marrow loses its ability to produce enough mature blood cells, such as white blood cells to fight infection and red blood cells to transport oxygen to different parts of the body.
"A percentage of people with MDS can and will develop leukemia," Brooks said.
But MDS also can be an "uncommon" albeit "significant, serious" complication of prior cancer chemotherapy, Brooks added.
And Roberts underwent chemotherapy to beat back early-stage breast cancer five years ago.
It's unclear what type of chemotherapy Roberts underwent at that time, but dose-dense chemotherapy, in which high-dose chemotherapy is given at relatively close intervals, can predispose people to MDS more than other forms of chemo, Brooks said.
According to the U.S. National Cancer Institute, MDS that is a consequence of past chemotherapy can be harder to treat than MDS unrelated to chemo.
Roberts said she would receive a bone marrow transplant from her older sister later this year, a procedure that will necessitate taking several months' leave from "Good Morning America."
Bone marrow transplantation is a risky, complicated procedure unto itself, Brooks said.
"Bone marrow transplantation at age 51 carries a certain risk of death, probably 10-15 percent and the chances of cure from this transplant are there, but perhaps only in the 30-40 percent range," he noted.
On the other hand, there are really no other treatment options for MDS, Brooks said.
Roberts said she received news of her diagnosis on the day that "Good Morning America" outperformed its archrival, the "Today" show, for the first time in 16 years.
She also underwent painful bone marrow testing the day she found out she would be interviewing President Barack Obama the next day.
"The combination of landing the biggest interview of my career and having a drill in my back reminds me that God only gives us what we can handle and that it helps to have a good sense of humor when we run smack into the absurdity of life," she wrote on ABC News' website.
Roberts remains upbeat about her diagnosis and her prognosis.
"My doctors tell me I'm going to beat this -- and I know it's true," she wrote on the website.
Find out more about MDS at the U.S. National Cancer Institute.
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