Archbishop Desmond Tutu is shown at an event in St. Paul, Minn., on July 20. South African retired Archbishop Desmond Tutu has cancelled travel plans for the rest of the year so he can undergo new treatment for prostate cancer, a foundation said. The Desmond and Leah Tutu Legacy Foundation said in a statement Tuesday that the Nobel Peace Prize laureate is starting a new course of medication to manage “the prostate cancer he’s been living with for the past 15 years.”