After undergoing surgery in May to remove a "very aggressive" cancerous tumor, Elvis Costello is ending his European summer tour early. "The spirit has been more than willing but I have to now accept it is going to take longer than I would have wished for me to recover my full strength," the 63-year-old singer-songwriter says in a Friday statement. He said the decision to cancel six remaining dates in England, Croatia, and Sweden was "strongly advised" by his doctor. Costello did not specify what type of cancer it is, though he said the surgery was successful, notes Billboard. Despite the cancellation, the singer is still expected to release his 31st studio album in October, per the BBC. (More Elvis Costello stories.)