( ( ( ( ( Leukemia , ) or ) ( cancer ( of ( the blood ) ) ) ) , ) ( ( is ( ( the ( ( most common ) type ) ) ( in children ) ) ) . ) )
(ROOT (S (NP (NP (NNP Leukemia)) (, ,) (CC or) (NP (NP (NN cancer)) (PP (IN of) (NP (DT the) (NN blood)))) (, ,)) (VP (VBZ is) (NP (NP (DT the) (ADJP (RBS most) (JJ common)) (NN type)) (PP (IN in) (NP (NNS children))))) (. .)))
Leukemia, or cancer of the blood, is the most common type in children.
(ROOT (S (NP (NNP Leukemia)) (VP (VBZ is) (NP (NP (DT the) (ADJP (RBS most) (JJ common)) (NN type)) (PP (IN of) (NP (NP (NN cancer)) (VP (VBN developed) (PP (IN in) (NP (NNS children)))))))) (. .)))