Cancer specialists said the treatments have saved the lives of thousands of patients with blood cancers. And, he said, “I haven’t seen a single one” develop a new T cell cancer. When patients’ T cells are engineered to make proteins that attack cancer cells, a virus helps slip new genes into T cell DNA. Even without chemotherapy or radiation, Dr. Maus added, patients with blood cell cancers are especially susceptible to developing other blood cell cancers. But Dr. DiPersio said, “it is more of a smoking gun.”The F.D.A.

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Persons: Marcela V, Maus, John DiPersio, Louis, “, ”, DiPersio, —, . Maus Organizations: Massachusetts General Hospital, Washington University School of Medicine Locations: Massachusetts, St