Inflammatory Myofibroblastic Tumor Treated with Laparoscopic Proximal Gastrectomy and Double-Tract Anastomosis

Inflammatory myofibroblastic tumors (IMTs) of the stomach are extremely rare in adults, and their oncologic prognosis is not well understood. We present a 28-year-old man with a proximal gastric IMT. The patient visited the emergency department of Yeouido St. Mary's Hospital with syncope and hematemesis. Hemoglobin levels were <5.5 g/dl. Gastric fibroscopy showed a protruding mass $4{\times}4cm$ in size, with central ulceration on the posterior wall of the fundus and diffuse wall thickening throughout the cardia and anterior wall of the upper body. Endoscopic biopsy revealed indeterminate spindle cells, along with inflammation. Given the risk of rebleeding, an operation was performed despite the uncertain diagnosis. Because the mass was circumferential, laparoscopic proximal gastrectomy and double-tract anastomosis were performed to ensure a safe resection margin. The pathological diagnosis was consistent with an IMT originating from the stomach, although the tumor was negative for anaplastic lymphoma kinase gene mutation.