Inherited Syndromes Causing Gastric Polyps

Adenomatous Polyposis Syndromes with Gastric Involvement

The American Gastroenterological Association recommends that patients with Familial Adenomatous Polyposis (FAP) be screened for gastric adenomatous polyps and cystic fundic gland polyps, which are associated with hundreds to thousands of colorectal polyps 1, 3
The American College of Gastroenterology states that FAP is caused by germline mutations in the APC gene, leading to autosomal dominant inheritance, and is associated with gastric polyps, duodenal adenomatous polyps, and extracolonic features such as CHRPE, osteomas, and desmoid tumors 1, 3
The National Comprehensive Cancer Network guidelines indicate that Attenuated Familial Adenomatous Polyposis (AFAP) presents with gastric AP and cystic fundic gland polyps similar to classic FAP, but with fewer colorectal polyps, and is also caused by APC gene mutations 1, 2, 3

The International Cancer Genome Consortium reports that Peutz-Jeghers Syndrome (PJS) causes hamartomatous polyps in the stomach and throughout the GI tract, due to germline mutations in the STK11 gene, and is associated with distinctive mucocutaneous hyperpigmentation and an increased risk of gastric cancer 1, 2, 3, 4
The American Cancer Society states that Juvenile Polyposis Syndrome (JPS) produces juvenile hamartomatous polyps in the stomach, in addition to colorectal involvement, and is caused by mutations in the BMPR1A or SMAD4 genes, with a 21% risk of gastric cancer in those with gastric polyps 1, 2, 3, 5, 6

The European Journal of Human Genetics notes that PTEN Hamartoma Tumor Syndrome (PHTS) includes gastric juvenile polyposis-type polyps, along with hyperplastic and adenomatous polyps, due to PTEN gene mutations, and is associated with trichilemmomas, ganglioneuromas, and macrocephaly 1, 2, 3
The National Institute of Health guidelines indicate that Hereditary Mixed Polyposis Syndrome (HMPS) may involve gastric polyps, though specific gastric involvement is less well-characterized, and is caused by GREM1 or BMPR1A gene mutations 1, 2, 3

The American Gastroenterological Association recommends that FAP/AFAP patients with gastric polyps be recognized by the hallmark gastric finding of cystic fundic gland polyps alongside adenomatous polyps 1, 2, 3
The International Cancer Genome Consortium reports that PJS mucocutaneous pigmentation may fade with age and be absent in adults, so absence does not exclude diagnosis 6, 8, 4
The American Cancer Society states that JPS gastric polyps specifically confer a 21% gastric cancer risk, making surveillance critical 5, 6, 7
The European Journal of Human Genetics notes that solitary juvenile polyps in children are common and not associated with cancer risk, unlike syndromic juvenile polyposis 5, 6, 8
The National Institute of Health guidelines indicate that SMAD4 mutations in JPS require evaluation for HHT-related vascular malformations 1, 2