The Princess Margaret Cancer Centre, previously called Princess Margaret Hospital, is a scientific research centre and a teaching hospital in Toronto, Ontario, Canada, affiliated with the University of Toronto Faculty of Medicine as part of the University Health Network. The hospital now stands as the largest cancer centre in Canada and one of the five largest cancer centres in the world. Along with the Odette Cancer Centre, which is also associated with University of Toronto Faculty of Medicine and is independently the sixth largest cancer centre in North America, it forms one of the largest cluster of cancer hospitals in the world.