Characteristics and concomitant congenital abnormalities among newborns with cancer: A population level analysis.

10071 Background: Congenital cancers are rare, occurring in 223 per million infants annually. Neuroblastoma, leukemia, and CNS tumors are most common. Up to one-third of cases involve genetic predispositions, emphasizing the need to understand developmental abnormalities for improved surveillance, prognosis, and targeted therapies. Methods: A retrospective population-based cohort study was conducted utilizing the Texas Inpatient Public Use Data File (TIPUDF) from 2016 to 2023. The target population consisted of all hospitalizations with Newborn in the source of admission column of the TIPUDF. Hospitalizations discharged more than one year after birth were excluded from the study. The primary exposure was a diagnosis of cancer identified using International Classification of Diseases, Tenth Revisions, Clinical Modification (ICD-10-CM) codes selected from diagnosis chapter NEO: Neoplasms and beginning with C. Outcome variables were selected from diagnosis chapters MAL: Congenital Malformations, Deformations and Chromosomal Abnormalities and PNL: Certain Conditions Originating in the Perinatal Period. Continuous variables are summarized as mean and standard deviation (SD) categorical variables are summarized as counts and percentages. Fisher’s exact test and t-tests assessed group differences, with the standardized mean difference (SMD) used as an effect size. Results: Out of the 2,906,295 newborn admissions in the TIPUDF from 2016-2023, 136 had a diagnosis of cancer. Compared to newborn admission without cancer, newborn admissions with cancer were more often male (62.5% vs 51.0%). Compared to newborns without cancer, newborns with cancer were associated with higher rates of congenital malformations, deformations and chromosomal abnormalities including atrial septal defects (38.2% vs 1.7%, SMD = 1.0256, p < 0.0001), anomalies of the aorta (1.6% vs 39.7%, p < 0.0001), undescended testicles (0.5% vs 2.9%, SMD = 0.1932, p < 0.0037), ventricular septal defects (15.4% vs 0.7%, SMD = 0.5647, p < 0.0001), Atresia and stenosis of urethra and bladder neck (2.2% vs 0.0%, SMD = 0.2119, p < 0.0001), Cleft lip/palate (2.2% vs 0.1%, SMD = 0.1935, p = 0.0009), anomalies of ureter (1.5% vs 0.0%, SMD = 0.1695, p < 0.0003). Newborns with cancer were more frequently affected by maternal conditions and complications including polyhydramnios (2.9% vs 0.2 %, SMD = 0.2260, p < 0.0001) and maternal infectious and parasitic diseases (7.4% vs 2.6%, SMD = 0.2193, p = 0.0032). Conclusions: Congenital cancers are rare but closely linked to congenital abnormalities and maternal complications, emphasizing the importance of early detection and tailored care. Future studies should explore underlying mechanisms and design effective surveillance strategies to enhance early diagnosis and outcomes.