Joan Lunden has been diagnosed with breast cancer, the former "Good Morning America" host announced on the program Tuesday.Lunden, 63, said the diagnosis came after an ultrasound after her yearly mammogram.Celebrities who have battled cancer"I knew the minute the doctor came in the door. I could tell by her demeanor. 'You have breast cancer.' The words are so surreal," she told "GMA"'s Robin Roberts.Lunden said her cancer is a more aggressive form, and she has already started chemotherapy. She will also undergo surgery and radiation treatments."You can't be afraid. That is what can really cause problems," she said.Lunden said her husband and seven children have been by her side through the process.Lunden co-hosted "GMA" from 1980 until 1997.

Joan Lunden has been diagnosed with breast cancer, the former "Good Morning America" host announced on the program Tuesday.

Lunden, 63, said the diagnosis came after an ultrasound after her yearly mammogram.


Celebrities who have battled cancer

"I knew the minute the doctor came in the door. I could tell by her demeanor. 'You have breast cancer.' The words are so surreal," she told "GMA"'s Robin Roberts.

Lunden said her cancer is a more aggressive form, and she has already started chemotherapy. She will also undergo surgery and radiation treatments.

"You can't be afraid. That is what can really cause problems," she said.

Lunden said her husband and seven children have been by her side through the process.

Lunden co-hosted "GMA" from 1980 until 1997.