GARDNER SYNDROME PHENOTYPE WITHOUT GENE MUTATIONS

Gardner syndrome (GS) is a variant of familial adenomatous polyposis and is originally described by adenomatous polyposis of colon, osteomas in the skull and mandible, and epidermoid cysts. However, it may include soft tissue abnormalities, such as desmoid tumors, lipomas, and fibromas. We report a case of 61-year-old man complaining of poor oral condition, with a previous medical history of rectum adenocarcinoma (2013) and abdominal desmoid tumor (2017). During radiographic examination, multiple radiopaque lesions were observed in the body and ramus of mandible. Computed tomography of the mandible was requested, and a biopsy of 1 of the lesions was performed. Histopathologic examination was compatible with osteoma. He started genetic evaluation but APC and MUTYH genes were negative for pathogenic mutations. Although the genetics gave negative results, the clinical evaluation was very suggestive of GS. He maintained his condition in our service until he died.