Clinical and genetic features of pediatric hereditary polyposis syndromes in Israel: A nationwide multicenter cohort.

OBJECTIVES

Hereditary polyposis syndromes in children are rare, heterogeneous disorders associated with significant morbidity and long-term risk of malignancy. Current data on their presentation, management, and outcomes in pediatric populations remain limited.

METHODS

We conducted a nationwide, multicenter, retrospective study that included children diagnosed with polyposis syndromes in eight pediatric gastroenterology centers in Israel. Demographic, genetic, clinical, endoscopic, and outcome data were collected.

RESULTS

A total of 105 children were included: 30 with juvenile polyposis syndrome (JPS), 26 with familial adenomatous polyposis (FAP), 19 with Peutz-Jeghers syndrome, 16 with phosphatase and tensin homolog-hamartoma tumor syndrome, 8 with constitutional mismatch repair deficiency syndrome, 5 with hereditary mixed polyposis syndrome, and 1 with Lynch syndrome. The median age at diagnosis was 8 years (interquartile range 4.1-11.5). Overall, 43 (41%) were of Ashkenazi Jewish origin, and a family history of polyposis was present in 54 (51%). Genetic testing was performed in 91 (87%), identifying pathogenic variants in 77 (73%) of them. Gastrointestinal symptoms were reported in 60 (57%) and extra-intestinal manifestations in 48 (46%). Polyposis-related surgery was required in 22 (21%) children. Malignancy in eight children included two cases of colorectal carcinoma and glioblastoma multiforme, T cell lymphoma with Wilm's tumor, medulloblastoma, ganglioneuroblastoma, and abdominal adenocarcinoma. Three mortality events were recorded.

CONCLUSION

Israeli children with hereditary polyposis syndromes present with diverse clinical and genetic features. Despite increasing use of genetic testing, morbidity and malignancy risks remain substantial, highlighting the need for early recognition, surveillance, and multidisciplinary care.