104: Neoadjuvant Imatinib Permits Robotic Duodenal Sleeve Resection for Gastrointestinal Stromal Tumor

Introduction: Gastrointestinal stromal tumors (GISTs) are most commonly found in the stomach (60%) and small intestine (30%). However, 5% present in the duodenum, which can be a challenging location for surgical resection. While surgery is the mainstay of treatment, patients with high tumor burden or metastatic disease can be treated with Imatinib, a tyrosine kinase inhibitor. This video presents the case of a 73-year-old male presenting with symptomatic anemia who was found to have a duodenal GIST.
 


Methods: CT imaging revealed a 3.3 by 2.9 cm mass in the second portion of the duodenum which was later confirmed to be a GIST on FNA via EUS. Given the location and size of the mass, the patient was likely to require a pancreaticoduodenectomy if resection was pursued at presentation. After discussion with the patient, neoadjuvant Imatinib was initiated with the goal of allowing a less morbid resection.
 


Results: Repeat imaging after 3 and 6 months of Imatinib showed an 18% and 30%, respectively, reduction in tumor size. Given this reduction, the patient was taken to the operating room for surgical resection. Diagnostic laparoscopy confirmed no evidence of metastases. After a generous Kocher maneuver, the mass could be visualized arising from the 2^nd and 3^rd portions of the duodenum. The proximal duodenum and distal jejunum were divided with a stapler, allowing for removal of the mass. A Fogarty catheter was then inserted through the cystic duct and observed within the duodenum, confirming the ampulla of Vater remained intact following resection. Reconstruction with a stapled lateral duodenojejunostomy was then performed and a drain left in place. The patient recovered well without apparent complications and was discharged on post-operative day 5. At 1.5 year follow up, the patient had no evidence of recurrence.
 


Conclusions: Neoadjuvant imatinib may provide significant tumor reduction, sparing the need for a Whipple for duodenal GIST.