robin roberts*Wow, Robin Roberts is dealing with another medical setback

The “Good Morning America” anchor announced on the ABC show Monday morning that she has been diagnosed with myelodysplastic syndrome, a blood and bone marrow disease once known as preleukemia.

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It will require her to start chemotherapy and get a bone marrow transplant.

She says she will undergo chemo and a bone marrow transplant this year as “pretreatment” for the disease, which she says she has known about for several weeks. She says her sister is a great match for her. While she says she’ll miss a day here and there, she’ll remain on the air.

Roberts battled breast cancer five years ago.

Watch as an emotional Robin explain her condition:

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