Navigating the Jejunal Junction: Surgical Management of a Proximal Jejunal GIST Involving the Transverse Mesocolon - A Technical Challenge

Abstract

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. Although the stomach is the predominant site, 20–30% arise in the small intestine, with proximal jejunal GISTs being particularly rare. Their location near the duodenojejunal (DJ) flexure and proximity to major mesenteric vessels pose significant operative challenges. Complete surgical excision with negative margins (R0) remains the cornerstone of treatment. Case Reported-We report the case of a middle aged male presenting with a one year history of intermittent upper abdominal pain. Imaging revealed a large enhancing lesion arising from the proximal jejunum. Image guided biopsy confirmed a spindle cell GIST. Intraoperatively, a 10 × 8 cm mass located 5 cm distal to the DJ flexure was found to infiltrate the distal transverse mesocolon and was closely related to the inferior mesenteric vein (IMV). A multivisceral en bloc resection was performed, including 30 cm of proximal jejunum and 7 cm of distal transverse colon, with vascular control achieved through meticulous identification and ligation of feeding vessels. Reconstruction was completed using stapled side to side duodenojejunal and transverse colonic anastomoses. The postoperative course was uneventful. Histopathology confirmed a malignant spindle cell GIST with negative margins; the patient was commenced on adjuvant imatinib based on risk stratification. Learning Point- This case highlights the unique technical considerations in managing proximal jejunal GISTs, emphasising the importance of meticulous dissection, preservation of vascular supply, and strategic operative planning to achieve R0 resection and optimal outcomes.