An immunotherapy harnessing the immune system's "natural killer" cells has proven effective in treating acute myeloid leukemia (AML) in some adults whose cancers return. Now, researchers at Washington University School of Medicine in St. Louis have shown, in a small clinical trial, that the same natural killer cells also can help some children and young adults with recurrent AML and few other treatment options. Results from the phase 1 trial, which included eight patients ages 1 to 30 years, are published online in the journal Blood. "All of the patients enrolled in this study had very aggressive AML," said first...