Metabolic syndrome in childhood, adolescent, and young adult cancer survivors: recommendations for surveillance from the International Late Effects of Childhood Cancer Guideline Harmonization Group.

Objective
Survivors of childhood, adolescent, and young adult (CAYA) cancer have an increased risk of metabolic syndrome (MetS). MetS describes the clustering of cardiovascular risk factors including overweight or obesity, hypertension, impaired glucose tolerance, and hyperlipidaemia. While associated cardiovascular sequelae can be serious, MetS is preventable, manageable and potentially reversible with the appropriate pharmacological and/or behavioral interventions. To optimise health outcomes in CAYA cancer survivors, international, harmonised surveillance recommendations are essential.Design
Systematic review and guideline development.Methods
A multidisciplinary guideline panel evaluated concordances and discordances across national guidelines for MetS surveillance and performed a systematic literature review. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to grade the available evidence and formulate recommendations considering the strength of the underlying evidence as well as potential harms and benefits associated with MetS surveillance. In case evidence was lacking, recommendations were based on expert opinion. In addition, recommendations for surveillance modalities were derived from existing guidelines for MetS components where applicable.Results
The systematic literature review included 20 studies and highlighted two high-risk groups, namely CAYA cancer survivors treated with total body irradiation and those treated with cranial or craniospinal irradiation (moderate-quality evidence). Recommendations were formulated for MetS surveillance in these risk groups, covering preferred screening modalities, age at screening initiation and surveillance frequency.Conclusions
In this international surveillance guideline for MetS in CAYA cancer survivors we provide evidence-based recommendations for clinical practice, with the aim of ensuring optimal MetS surveillance for CAYA cancer survivors.