Four persons of a family, including a cancer patient they were shifting to a different hospital, were killed and another injured when a truck hit their car in Odisha's Dhenkanal district on Monday, police said.The accident occurred on the National Highway-55 near Nadhara.While one woman and three men were killed, one was injured, said police, adding the injured has been admitted to a community health centre at Hindol.The family were shifting a cancer patient undergoing treatment at SCB Medical College and Hospital, Cuttack, to Veer Surendra Sai Institute of Medical Sciences and Research (VIMSAR), Burla when the accident took place.All were residents of Landijhari village in Deogarh district, police added.