Sen. John McCain (R-AZ) spoke candidly on Sunday about his brain cancer diagnosis, saying he is optimistic but cognizant of the “vicious[ness]” of the disease. “I’m not trying to paint this as a rosy picture. This is a very virulent form of cancer. It has to be fought against,” McCain said on CNN’s State of the Union. “Every life has to end one way or another.” McCain added that the “prognosis is pretty good” and “all the results so far are excellent.” The former GOP presidential nominee said he is getting an MRI on Monday for further evaluation following rounds of chemotherapy and radiation treatment.