Atypical presentation of myoepithelial hamartoma in the antrum of the stomach, mimicking a gastrointestinal stromal tumor: a case report

INTRODUCTION: A myoepithelial hamartoma is a very uncommon submucosal tumor of the stomach. In an atypical presentation in our case, it mimicked the clinical presentation of a gastrointestinal stromal tumor. To the best of our knowledge, it is the first case of a hamartoma of the stomach reported from Bangladesh and one of few cases described in the literature. CASE PRESENTATION: We describe the case of a 35-year-old Bengali man with recurrent epigastric pain and occasional vomiting with radiographic findings of a gut mass. An upper gastrointestinal endoscopy revealed a healed duodenal ulcer, deformed ‘D’ bulb and a submucosal swelling in his antrum. Ultrasonography and a contrast-enhanced computed tomography scan confirmed the presence of a well-defined, oval gut mass in his upper abdomen, compressing his duodenum. The mass had a mixed density and was considered to probably be a gastrointestinal stromal tumor. Ultrasonography-guided fine needle aspiration cytology was inconclusive. After resection at laparotomy, a histopathological examination revealed a myoepithelial hamartoma. These tumors are characterized by hypertrophic smooth muscle bands surrounding varied epithelial elements, which may be arranged in diverse patterns such as simple glandular structure, Brunner’s gland, pancreatic ducts and sometimes pancreatic acini. This case report is complemented by a literature review relating to the atypical presentation. CONCLUSION: Gut masses need to be investigated thoroughly and the possibility of rare tumors should not be excluded. Although the recommended treatment for such lesions is limited resection, radical procedures such as a pancreaticoduodenectomy are often performed when the lesion occurs in the periampullary area because of preoperative misdiagnosis as a carcinoma. Therefore, it is essential for clinicians to maintain current knowledge of the lesion to avoid inaccurate diagnosis and prevent unnecessary surgery.