Sen. John McCain, one of the toughest men in Washington, is now heading into the most difficult fight of his life.

The 80-year-old Republican from Arizona, who often jokes he is, “older than dirt,” is admired for surviving five years of torture at the infamous “Hanoi Hilton” while he was a prisoner during the Vietnam War.

Now, his survival is again in jeopardy, in the wake of the grim diagnosis of glioblastoma, a highly aggressive form of brain cancer.

McCain’s glioblastoma was discovered after he complained of double vision during a routine physical exam. An MRI indicated a mass of cells above his left eye, which was surgically removed and determined to be cancerous.  It is unknown whether McCain’s condition contributed to his somewhat confused line of questioning during fired FBI Director James Comey’s appearance on Capitol Hill in June.

Read more on the story here: John McCain diagnosed with cancer