Benign Pyloric Adenomyoma Presented As Gastric Outlet Obstruction: a Case Report and Review of the Literature

Background: Gastric adenomyoma is a rare benign tumor composed of glandular structures and smooth muscle fibers. While some classify gastric adenomyoma as a hamartoma, others view it as an abortive form of heterotopic pancreas. Despite its benign nature, there is a risk of malignant transformation. Predominantly found in the antrum, gastric adenomyoma affects all ages but is most common in adults aged 40-60 years. Symptoms are nonspecific, and its similarity to other lesions complicates diagnosis. This paper aims to provide a review of medical literature on gastric adenomyoma and its diagnosis and treatment methods, along with presenting an additional case report on the same topic.

Case Presentation: We present the case of a 55-year-old Syrian man who experienced vomiting, weight loss, and chronic partial constipation. An obstructing mass in the pylorus was detected, and then an open surgery was performed to excise the lesion. A biopsy of the resected mass was obtained for histopathological examination. The final diagnosis of the lesion was pyloric-region adenomyoma with severe pyloric stenosis. After the successful surgery, the patient recovered without any recurrence or complications.

Conclusions: Several diagnostic approaches are available, including radiological studies, endoscopic examination, and fine needle aspiration guided by endoscopic ultrasonography. Treatment options involve endoscopic submucosal dissection and complete laparotomy resection. Further studies and thorough reviews are recommended to better understand the best clinical practices. Practitioners should consider gastric adenomyoma when encountering a mural gastric lesion.