Joan Lunden has been diagnosed with breast cancer.

The former “Good Morning America” host, 63, shared the news Tuesday.

“I have covered many stories about breast cancer over the years but I never actually thought this would happen to me,” she said in a statement. “I have shaped my career around health and wellness advocacy so it seemed natural to share my story. I’ve started chemotherapy and while I don’t know how I’ll look and feel down the road, I am assuming the best because that is how I live my life.”

Lunden says she received the news after a routine mammogram and ultrasound, which revealed a tumor in her right breast.

“After a core biopsy was performed, I heard those words that every woman fears and that I never thought I’d hear: ‘you have breast cancer,’” wrote Lunden in a blog post.

Although she thought to keep it secret, Lunden decided to share the news with the world because it’s what she’s always done.

“I have shared my journey. So it certainly didn’t feel right keeping this part of my journey a secret.”

The former “GMA” anchor’s course of treatment will include a lumpectomy, chemotherapy and radiation. She is expected to make a full recovery.