so is this there something wrong with the senate chamber
He's 80 years old, he was around for a time when the causes of cancer were not well known yet. When he was a child he could have encountered an x-ray machine in a shoe store, among other places. At the time it wasn't known that radiation causes cancer, so x-ray machines were used quite a bit and weren't designed to use short bursts of x-ray like current machines use to minimize radiation exposure.
In other words, he probably was exposed to lots of cancer causing things while he was growing up. It's really not surprising when people around that age get cancer.