Joan Lunden Joan Lunden

Former Good Morning America anchor Joan Lunden returned to the morning show Tuesday to reveal that she was recently diagnosed with breast cancer.

Lunden, who hosted GMA from 1980 to 1997, spoke with current co-host Robin Roberts, who survived breast cancer. She also published a blog post on her website Tuesday discussing her diagnosis, which she received after getting an ultrasound in addition to her annual mammogram.

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Lunden, 63, says she initially considered trying to keep her cancer private, but opted to share the news. "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 wrote in her post. "I have shared my journey. So it certainly didn't feel right keeping this part of my journey a secret."

The former anchor says she was inspired by her late father, who was a cancer surgeon. "I knew that he would want me to use this experience as an opportunity to spread the word about how important it is to get screened for all types of cancers and for women to do self-breast exams," she writes. "I know I have a challenge ahead of me in this journey, however I have chosen to take it as an opportunity to fulfill my father's legacy and try to inspire others to protect their health."  

Lunden's treatment will consist of a lumpectomy and radiation, she told Roberts, and she describes her prognosis as "promising."