Most common cancer in children is

Acute lymphoblastic leukemia/lymphomas (ALLs) are neoplasms composed of immature B (pre-B) or T (pre-T) cells, which are referred to as lymphoblasts. About 85% are B-ALLs, which typically manifest as childhood acute "leukemias."ALL is the most common cancer in children.Ref: Robbins and Cotran Pathologic Basis of Disease; 9th edition; Chapter 11; Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus; Page no: 590