Good Morning America: Robin Roberts reveals diagnosis that requires bone marrow transplant

NEW YORK - On Good Morning America Monday, Robin Roberts announced another medical battle in her life after beating breast cancer five years ago.

A tearful Roberts said she was diagnosed with MDS or myelodysplastic syndrome, a disease of the blood and bone marrow.

Roberts told the national TV audience that she was beginning pretreatment Monday, chemotherapy leading up to a bone marrow transplant later in the year. She said her sister will be her donor and will be an excellent match, which will help her chances.

"It's about focusing on the fight and not the fright," Roberts said.

Roberts’ GMA co-hosts and "family," George Stephanopoulos, Josh Elliott, Lara Spencer and Sam Champion, offered their support on the show.

“We want you to know we love you and we know you’re going to beat this,” Stephanopoulos said.

“It is our fight, not yours,” Elliott said.

Roberts said she was diagnosed several weeks ago.

"I am going to beat this," Roberts said.

She said she may miss a day occasionally but will continue to anchor GMA until she needs to miss a larger chunk of time for the transplant.

To read a letter Roberts wrote describing what's ahead, click here: http://on.wews.com/MBMAnG