A four-year-old boy has been successfully treated for an acute form of leukemia via the use of immune-system cells that were genetically manipulated to make them capable of identifying and attacking the cancer, doctors at Rome's Bambino Gesù pediatric hospital said on Thursday.

The child is the first Italian patient to benefit from this revolutionary therapy. The condition was resistant to conventional therapies. The child is well and left the hospital a month after being treated with the reprogramed cells. Leukemia cells are no longer present in his bone marrow, the doctors said.