A Rare Case of Leiomyosarcoma Arising From the Stomach: A Case Report and Review of the Literature.

Leiomyosarcomas (LMSs) account for 10-20% of all soft-tissue sarcomas (STSs). Soft-tissue sarcomas, and more specifically LMS, typically originate from the uterus, extremity, retroperitoneal, or lower intraabdominal gastrointestinal organs. Due to the rarity and variability in presentation, it is difficult to describe identifiable risk factors, determine etiology, predict disease progression, and prognosticate these types of neoplasms. We present the case of a 77-year-old woman presenting to the emergency department with shortness of breath. After being diagnosed and treated for mild exacerbation of congestive heart failure, she was incidentally found to be anemic. Further workup, including an esophagogastroduodenoscopy, revealed a bleeding gastric mass, which was biopsied. Histopathology and immunohistochemistry confirmed the mass to be primary gastric LMS. Due to its rarity, an interdisciplinary approach involving clinical, histopathologic, and immunohistochemical data is necessary to successfully identify and diagnose gastrointestinal LMS. This case report aims to contribute to the paucity of information available in the literature regarding gastric LMS so that it may be better understood.