Joan Lunden, the former Good Morning America co-host, revealed Tuesday that she’s battling breast cancer.

Joan Lunden Has Breast Cancer

Lunden, 63, announced the health news on GMA, speaking to co-anchor and breast cancer survivor Robin Roberts. Lunden, who co-hosted GMA from 1980 to 1997, told Roberts that she’d soon begin chemotherapy and other treatments to fight her cancer, which she said was “the aggressive kind.”

After stopping by the GMA studios, Lunden took to Twitter to thank Roberts and the morning show for offering their support.

Lunden also opened up on her blog about the reasoning behind making her diagnosis public.

"I have decided to talk about my breast cancer because since the moment I took the job at Good Morning America," Lunden wrote. "I have lived my life sharing my joys and my disappointments with all of you: my pregnancies, my relationships, my career… I have shared my journey. So it certainly didn’t feel right keeping this part of my journey a secret."

In addition to Lunden and Roberts, GMA news anchor Amy Robach has also been public with her battle against breast cancer. Robach, 41, recently completed chemotherapy and is in remission.

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