Unusual location of gastrointestinal stromal tumor (GIST): A case report and literature review of greater omentum location.

INTRODUCTION

Gastrointestinal stromal tumors (GISTs) represent a unique subset of neoplasms within the digestive tract. They can manifest in various organs throughout the digestive tract, ranging from the oral cavity to the anus, with a predilection for the stomach and small intestine. A distinct subtype of GISTs, known as Extra-gastrointestinal stromal tumors (EGISTs), originate outside the typical GIST organs such as the mesentery, retroperitoneum, and occasionally the omentum. EGISTs are relatively rare, accounting for <5 % of all GIST cases.

PRESENTATION OF CASE: We present the case of a 30-year-old female patient who presented with an upper abdominal mass associated with anorexia, fever, and weakness. Radiographic imaging revealed a cystic mass beneath the left hypochondrium. Exploratory laparoscopy confirmed the presence of an isolated mass adherent to the gastrocolic ligament and greater omentum. Histopathological examination confirmed GIST, characterized by spindle-shaped cells with DOG1 and CD117/C-kit expression. The patient underwent successful tumor resection and was discharged home with postoperative imatinib therapy. Follow-up at 14 months showed no recurrence.

DISCUSSION: The rarity of Gastrointestinal Stromal Tumors (GISTs) in the Greater Omentum highlights diagnostic challenges and underscores the need for further research. Immunohistochemical analysis aids in diagnosis, with Ki-67 staining indicating a high-risk classification. Surgery remains the primary treatment, with potential adjuvant therapy utilizing Imatinib mesylate.

CONCLUSION

Our case underscores the rare occurrence of GIST in the Greater Omentum. Despite their infrequency, EGISTs should be considered in intra-abdominal masses, emphasizing accurate diagnosis for appropriate management and the need for further research.