Familial adenomatous polyposis: an adolescent with refractory iron deficiency anemia and a mandibular mass.

Familial adenomatous polyposis is an autosomal dominant disease that results in numerous colonic polyps resulting in malignancy if left untreated. We report a case of a 15-year-old male with a strong family history of colon cancer who presented with refractory iron deficiency anemia and a mandibular mass. Colonoscopy revealed extensive large lobulated polyps and genetic testing confirmed familial adenomatous polyposis, while computed tomography scan revealed his mass to be a mandibular osteoma, a known extracolonic manifestation of familial adenomatous polyposis. The combination of colorectal and extracolonic manifestations is known as Gardner syndrome. In an adolescent with iron deficiency anemia refractory to adequate supplementation and a strong family history, the diagnosis of familial adenomatous polyposis should be considered. [ABSTRACT FROM AUTHOR]