Gastrointestinal Stromal Tumors (GIST): Clinical and Pathological Correlation

Abstract

Gastrointestinal Stromal Tumors (GISTs) are the most prevalent mesenchymal tumors of the gastrointestinal tract, originating from interstitial cells of Cajal. Characterized primarily by KIT or PDGFRA mutations, a subset also includes SDH-deficient GISTs, often linked to syndromic presentations. This report details a case of a 35-year-old female presenting with upper abdominal pain and swelling, diagnosed with a large gastric GIST. Clinical evaluation, including significant abdominal mass and CECT findings suggesting a gastric origin, led to an exploratory laparotomy and wedge resection. Pathological examination revealed a large, well-circumscribed gastric mass, with microscopic histopathology confirming a spindle cell neoplasm with low mitotic activity (3 mitoses per 5 mm²) and necrosis. Immunohistochemistry showed positivity for CD117 and DOG1, crucial for diagnostic confirmation and distinguishing GISTs from other mesenchymal tumors. Risk stratification based on tumor size, mitotic index, and location guided postoperative management, including adjuvant imatinib therapy for intermediate/high-risk cases. This case highlights the importance of integrating clinical presentation, imaging, histopathology, and immunohistochemistry for accurate diagnosis, risk stratification, and effective surgical and adjuvant management of GISTs.

Keywords: Gastrointestinal Stromal Tumors; GIST; KIT mutation; PDGFRA mutation; Imatinib; Clinical Correlation; Pathology; Surgical Treatment