On Tuesday, former Good Morning America host Joan Lunden revealed that she has been diagnosed with breast cancer. Lunden wrote a letter to her fans, which she posted on her website.

She appeared on Good Morning America on Tuesday to share her experience. “In the beginning, it’s such a shock, it’s a stunner, and you think, ‘I do everything right!’” she said. At first, Lunden was questioning what she did wrong, but she said that she is now in “warrior mode.”

She said that she has been getting mammograms and ultrasounds regularly, and according to her, nothing showed up in this year’s mammogram results. Her ultrasound, however, was a different story.

.@JoanLunden opens up to @RobinRoberts about her breast cancer diagnosis: pic.twitter.com/KVnnaD6sTO

— Good Morning America (@GMA) June 24, 2014

After a post-biopsy appointment with her doctor, she learned about her breast cancer. “The words are almost surreal, when you hear, ‘You have breast cancer,’” she said.

When she first heard of the news, Lunden, 63, initially considered keeping her condition a secret from the public. However, after thinking it through, she decided to share the news to the public.

“I have decided to talk about my breast cancer because since the moment I took the job at Good Morning America I have lived my life sharing my joys and my disappointments with all of you: my pregnancies, my relationships, my career,” she said. Lunden was one of the hosts of Good Morning America from 1980 up to 1997.

She continued to say that her cancer is part of her journey and she was not planning to keep it from everyone.

Reports state that Lunden has already started her chemotherapy sessions. Although she said that she does not know how she will feel in the future, she is “assuming the best because that is how I live my life.” Her rep also said that she is sceduled to undergo radiation and lumpectomy and is expected to make a full recovery.

To my friend and colleague @katiecouric, thank you so much for your support

— Joan Lunden (@JoanLunden) June 24, 2014

Image via YouTube