Until now, the 84-year old's biggest affliction appeared to be sciatica, a chronic nerve condition that causes back, hip and leg pain and has occasionally forced him to cancel official events. He has dubbed the condition "a troublesome guest".
Francis almost died when he was 21 after developing pleurisy -- an inflammation of the tissues that surround the lung -- according to biographer Austen Ivereigh. He had part of one of his lungs removed in October 1957.