Joan Lunden diagnosed with breast cancer - wave3.com-Louisville News, Weather & Sports

Joan Lunden diagnosed with breast cancer

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Lunden said the tumor was discovered via ultrasound and not during her annual mammogram. (Source: CNN) Lunden said the tumor was discovered via ultrasound and not during her annual mammogram. (Source: CNN)

CNN) - Former Good Morning America co-host Joan Lunden has been diagnosed with breast cancer.

Lunden revealed via Twitter and a letter on her website that the tumor was discovered via an ultrasound and not during her annual mammogram.

She told current GMA co-host and breast cancer survivor Robin Roberts that she has a particularly aggressive form of cancer.

Lunden says she is in "warrior mode" and learning everything she can about breast cancer as she undergoes chemotherapy.

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