Donnelly has had two moles that were cancerous in the past, and he is about to get the verdict on a new one.
"Absolutely no need to do surgery, or no need to do cutting," Rao said.
No surgery, no cutting from a biopsy, thanks to the device Rao held in his had -- a Viva Scope.
"It will take just a few images, which then will be visible on a monitor and I can tell right away if it is good or not good," Rao said.
The Viva Scope is applied directly to any part of the body. It takes only 60 seconds to look beneath the skin's surface. A certain image means cancer and an operation for total removal is needed, but a different image says it's nothing and no biopsy is needed.
"I think it will become much more common. I think I know it will save lives," Donnelly said.
At 70, Donnelly can walk away knowing he won't have unnecessary scars just to be sure he is skin cancer-free.
At present, Rao said insurance usually does not pay for the use of the Viva Scope, but patients whose doctors have the device can expect to pay $250 or more out of pocket.