Solid Tumor Incidence and Patterns in Individuals With Down Syndrome: A Systematic Review and Meta-Analysis

Background: Individuals with Down syndrome (DS) exhibit a distinct pattern of solid tumor occurrence. However, the incidence of specific solid tumors remains inconsistent. We aimed to assess the burden of solid tumors in individuals with DS and compare it to the general population. Methods: We conducted a systematic literature search across PubMed, Scopus, Web of Science, and Google Scholar to identify cohort studies reporting the incidence of solid tumors in individuals with DS. Statistical analyses were performed using random-effects model, along with subgroup analyses, heterogeneity evaluation, publication bias, and sensitivity analyses. Results: The systematic search identified 8049 records. Fourteen studies were included, representing 34,561 individuals with 452,409.72 person-years of follow-up. The pooled incidence rate of solid tumors in individuals with DS was 95 cases per 100,000 person-years (95% confidence interval [CI]: 42–170). Compared to the general population, individuals with DS exhibited a significantly lower incidence rate of solid tumors (standardized incidence ratio [SIR]: 0.69, 95% CI: 0.51–0.94), with significantly lower rates observed for female genital organ (SIR: 0.44, 95% CI: 0.20–0.99), breast (SIR: 0.35, 95% CI: 0.17–0.73), skin (SIR: 0.24, 95% CI: 0.11–0.50), and lung (SIR: 0.10, 95% CI: 0.02–0.62) cancers. In contrast, higher incidences were identified for testicular (SIR: 4.28, 95% CI: 2.61–7.03) and liver (SIR: 3.72, 95% CI: 1.09–12.75) tumors. Conclusions: This study provides a comprehensive overview of solid tumor epidemiology in individuals with DS, emphasizing the need for population-specific screening measures.