The bump on the back of the mouse is the size of a Tic Tac breath mint, or, possibly, a small pea. But for Matt Freedman, a New York artist grappling with a rare and deadly neck cancer, the tiny tumor - his tumor - represents a last-ditch hope for a healthy future.

(CNN) -- Spanish art dealer Jose Carlos Bergantiños Diaz helped persuade wealthy buyers to shell out millions of dollars for works he claimed famous masters of modern art had painted. But in reality, U.S. authorities allege, the works he sold as Rothkos and Pollocks were fakes painted by an artist he met on a Manhattan street corner.