RESUMO
BACKGROUND: Malignant neoplasms that affect children and adolescents are predominantly embryonic and generally affect blood system cells and supporting tissues. AIM: This study aimed to summarize the scientific evidence about the prevalence of malignant lesions in the oral cavity of children and adolescents. DESIGN: In this systematic review and meta-analysis (PROSPERO CRD42020158338), data were obtained from seven databases and the gray literature. Cross-sectional observational studies on the prevalence of biopsied oral pediatric malignancies were included. The Newcastle-Ottawa Scale assessed the quality of the included studies, and the GRADE approach evaluated the evidence certainty. The meta-analysis prevalence was calculated using MedCalc® software, adopting a 95% confidence level (CI; random-effect model). RESULTS: Forty-two studies were included in the meta-analysis. Of the 64,522 biopsies, the prevalence of malignant lesions was 1.93% (n = 1,100; 95% CI = 1.21%-2.80%). Countries with a low socioeconomic profile showed the highest prevalence. The sample size did not influence the prevalence of oral malignancies, and unspecified lymphomas (12.08%; 95% CI = 5.73%-20.37%) and rhabdomyosarcoma (10.53%; 95% CI = 7.28%-14.30%) were the most common lesions. CONCLUSIONS: Oral malignant lesions biopsied in children and adolescents had a prevalence of <3%, and lymphomas and sarcomas were the most prevalent lesions.