This July 2, 2013 photo released by ABC shows co-host Amy Robach the set of "Good Morning America," in New York. A month after undergoing a mammogram on "Good Morning America," ABC's Amy Robach said Monday, Nov. 11, she has breast cancer and will have a double mastectomy and reconstructive surgery this week. (AP Photo/ABC, Ida Mae Astute) Amy Robach on “Good Morning America,” in New York. (Ida Mae Astute/ABC/AP)

Amy Robach, the ABC News correspondent diagnosed with breast cancer last month after her on-air mammogram for “Good Morning America,” told viewers Friday that her prognosis is “good.” However, while Robach was undergoing a double mastectomy on Nov. 14, her surgeon detected a second malignant tumor and discovered the cancer has spread to a lymph node. “I will have more treatments ahead of me, but none that will take me out of work,” Robach, 40, wrote in an open letter, adding that she plans to be back at work the first week of December. “It brought so many tears of joy to my eyes and warmed my heart more than you’ll ever know to see what my ABC family did for me and for my entire family,” she wrote.

Earlier: Reliable Source: Amy Robach’s breast cancer diagnosis proves on-air medical tests are no laughing matter

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