I suspect Senator Kennedy's tumor is particularly aggressive as his Left carotid surgery last October would have included diagnostic tests revealing brain pathology--and both were coincidentally on the same Left side.
Presuming Kennedy had no brain pathology in October, the tumor has advanced to causing seizures in a relatively short time. Grim prognosis for the short term.
That makes a great deal of sense.
I recently had a brain scan (MRI, for those in Loma Linda), and the waiting period until you get the radiologist’s report is agonizing.