Here's a pretty frightening assessment of McCain's skin cancer from Dr. Daniel Vlock, a former cancer researcher:

"The best case scenario is that he continues to age but effectively is able to perform the duties of the job," said Fratkin. "The worst case scenario is on January 21 2009, he has a seizure at his inauguration and is found to have multiple brain metastases. There is no way to navigate that risk assessment without those records."

2,279 physicians have signed a letter asking McCain for "full, public disclosure of all his medical records". More than 47,000 people have signed the petition. Won't you join them?