The Children’s Oncology Group (COG), a clinical trials group supported by the National Cancer Institute (NCI), is the world’s largest organization devoted exclusively to pediatric cancer research. The COG conducts a spectrum of clinical research and translational research trials for infants, children, adolescents, and young adults with cancer.

The cooperative group system for clinical research began in 1955 with a consortium focused on childhood cancer research.

The group, with more than 7,500 experts worldwide, has nearly 100 active clinical-translational trials open at any given time.

These trials include treatment for many types of childhood cancers, studies aimed at determining the underlying biology of these diseases, and trials involving new and emerging treatments, supportive care, and survivorship. 

The group's research studies encompass hematologic malignancies, solid tumors, central nervous system tumors, and rare cancers. More than 90% of 13,500 children and adolescents diagnosed with cancer each year in the United States are cared for at COG member institutions.

According to en.wikipedia