'Pre-cancerous lesion': Clinical immunologist puts clues together on Trump's new rash

Donald Trump was spotted in public with a nasty new rash on his neck, and one clinical immunologist believes a pre-cancerous lesion could potentially be the culprit.

The 79-year-old president on Monday awarded the Medal of Honor at the White House to Vietnam veteran Terry P. Richardson, who is credited with saving the lives of 85 soldiers during a 1968 battle, and eagle-eyed observers noted that photos showed a heavy rash on the right side of Trump's neck at the event.

"Whoa -- this...