2025 Volume 11 Issue 1 Article ID: cr.24-0133
INTRODUCTION: Gastrointestinal stromal tumors (GISTs) are a relatively rare clinical entity. They usually appear as solid masses in numerous locations throughout the gastrointestinal tract, varying in size and typically exhibiting extraluminal expansion along with a range of nonspecific symptoms. The exophytic growth pattern of these tumors may occasionally complicate the differential diagnosis from other medical conditions with similar clinical and imaging findings.
CASE PRESENTATION: We describe a case of a 46-year-old male patient who presented to the emergency department with symptoms of upper gastrointestinal tract hemorrhage. Initial endoscopic findings suggested a large gastric diverticulum. Surprisingly, further investigation with computed tomography and a second endoscopy with biopsy sampling revealed that the stomach wall outpouching was actually a disguised, oversized gastric GIST. The patient underwent a posterior wall sleeve gastrectomy en bloc with the mass, the spleen, and the tail of the pancreas and recovered uneventfully. Daily administration of imatinib as adjuvant therapy was included in the treatment plan. No recurrence was observed even up to the 4-year follow-up period.
CONCLUSIONS: GISTs are uncommon tumors with the ability to masquerade as gastrointestinal tract diverticula, causing diagnostic confusion. Nevertheless, high clinical suspicion combined with a thorough clinical and imaging evaluation can ultimately lead to the correct diagnosis and an appropriate treatment plan.