Demi Lovato cancels hours before London show

"Swollen vocal cords" forced Demi Lovato to postpone her show at the O2 in London hours before she was due to appear on stage.In a statement on social media, written through "tears of frustration and sadness", she added that her vocal cords could have been injured had she performed, potentially threatening the rest of her tour.Lovato told her supporters it broke her heart to let them down, and that she was "so so sorry to disappoint any of my fans in London that have travelled hours to be here b