Prevalence of malignant neoplastic oral lesions among children and adolescents: A systematic review and meta-analysis

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 (R) 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.