The Children’s Oncology Group Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent, and Young Adult Cancers: A Review Abstract Importance Since 2003, the Children’s Oncology Group (COG) has developed and disseminated the Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent, and Young Adult Cancers. These guidelines have benchmarked the standard of care for long-term survivors of childhood cancer in North America and beyond.