Longtime Arizona senator and former Republican presidential candidate John McCain has been diagnosed with primary glioblastoma, a malignant form of brain cancer. Sen. McCain’s office said Wednesday the diagnosis came after McCain had surgery last week to remove a blood clot above his left eye. McCain is reportedly weighing whether to undergo an aggressive treatment of radiation and chemotherapy, and has not said when he might return to Capitol Hill. McCain’s cancer is the same form that claimed the lives of Senator Ted Kennedy and Vice President Joe Biden’s son, Beau Biden. McCain’s departure last week left Republicans with a narrow, 51-vote majority in the Senate as President Trump pushes for votes on healthcare and tax cuts.