Pieters R, De Lorenzo P, Ancliffe P, et al. - In the Interfant-06 study, researchers examined 18 national and international study groups to test if myeloid-style consolidation chemotherapy is superior to lymphoid style in infant acute lymphoblastic leukemia (ALL). Further, they examined the role of stem-cell transplantation and investigated the factors having independent prognostic value for these patients. They defined three risk groups: low risk = KMT2A germline; high risk = KMT2A-rearranged and older than 6 months with WBC count 300 × 10⁹/L or more or a poor prednisone response; and medium risk = all other KMT2A-rearranged cases. They evaluated 651 infants, with 6-year event-free survival (EFS) and overall survival of 46.1% and 58.2%, respectively. Observations revealed no significant improvement in outcome for infant ALL with early intensification with postinduction myeloid-type chemotherapy courses vs the lymphoid-type course IB. Infant ALL in Interfant-06 vs those in Interfant-99 displayed no improved outcome. The strongest prognostic factor for EFS was KMT2A rearrangement, followed by age, WBC count, and prednisone response.