A Population-Based Assessment of Cancer Risk in Children With VACTERL.

Cancer risk in children with VACTERL, a nonrandom co-occurrence of ≥ 3 defects (vertebral, anal, cardiac, tracheoesophogeal fistula, renal, and limb), remains unclear. We evaluated this association in a population-based study. We analyzed data from the Genetic Overlap Between Anomalies and Cancer in Kids (GOBACK) Study, a US registry linkage cohort. VACTERL was defined as the presence of ≥ 3 associated defects. Cox regression was applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer risk before age 18 in children with VACTERL compared to children without birth defects. Kaplan-Meier analyses were used to estimate cumulative incidence of cancer in each group. Of 21,224,742 births, 2288 met VACTERL criteria; 8 developed cancer, 5 (63%) of whom were diagnosed with embryonal tumors. Children with VACTERL had a significantly increased cancer risk (HR = 3.0, 95% CI: 1.5-6.0), particularly for embryonal tumors (HR = 6.9, 95% CI: 2.9-16.5), relative to unaffected children. Cancer incidence was 421.3 (95% CI: 181.9, 830.0) per million person-years for VACTERL versus 133.4 (95% CI: 131.8-135.0) for unaffected children. Children with VACTERL may face increased cancer risk. Shared developmental or epigenetic mechanisms may underlie both conditions, highlighting efforts to identify subgroups that may benefit from targeted surveillance.