Cancer Frequencies and Screening in Individuals With Down Syndrome: A Comprehensive Nationwide Cross-Sectional...

Down syndrome (DS) (trisomy 21) presents a distinctive cancer profile requiring risk-adapted surveillance strategies. This study examined cancer prevalence and screening participation patterns in individuals with DS to inform clinical care protocols.

This large-scale retrospective cross-sectional study analyzed German nationwide statutory health insurance outpatient data, comparing 46,362 individuals with DS (International Classification of Diseases [ICD]-10: Q90) with 463,620 matched controls without intellectual disability (including DS), stratified by age, sex, and residential district. Logistic regression analysis evaluated cancer occurrence and screening program participation between groups.

Cancer prevalence was lower in the DS group compared with the matched control group (2.4% v 2.8%; odds ratios [OR], 0.85 [95% CI, 0.80 to 0.91]; P < .00001; corrected: P = .00002) and occurred at younger age. However, individuals with DS demonstrated markedly elevated odds for hematologic malignancies: unspecified cell type leukemia (OR, 10.32), lymphatic leukemia (OR, 6.12), and myeloid leukemia (OR, 6.32), and testicular cancer (OR, 4.25). Conversely, breast cancer (OR, 0.36), digestive system tumors (OR, 0.39), and malignant melanomas (OR, 0.52) were significantly less frequent. Notably, individuals with DS participated less frequently in cancer screening programs (17.03% v 26.17%; OR, 0.58 [95% CI, 0.56 to 0.59]).

The distinctive cancer profile in DS reflects elevated leukemia and testicular cancer risks alongside protection against solid malignancies, consistent with the chromosomal biology of trisomy 21. Reduced screening participation may partially explain lower overall cancer prevalence and warrants future research. These findings underscore the need for syndrome-specific surveillance protocols targeting high-risk malignancies and further molecular characterization of cancer predisposition and protection mechanisms.