Former NBC Nightly News anchor and Yankton native Tom Brokaw announced Tuesday that he has been diagnosed with cancer. In a statement posted on NBCNews.com, Brokaw said he has multiple myeloma, a cancer affecting blood cells in the bone marrow. Brokaw, who turned 74 last Thursday, said doctors are optimistic about his prognosis. There is no cure for multiple myeloma, but treatments are available that slow its progression. Diagnosed in August, Brokaw has continued to do work for NBC, including contributing to the coverage of the Winter Olympic Games. Sanford Health oncologist Dr.