Gastrointestinal Stromal Tumor in the Excluded Gastric Remnant After Roux-en-Y Gastric Bypass.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the GI tract. Despite this, they rarely occur, accounting for only 1% to 3% of all gastrointestinal tumors. This report describes a 53-year-old female patient with surgical history of Roux-en-Y gastric bypass (RYGB) who presented with right upper quadrant abdominal pain. CT imaging revealed a large 20 × 12 × 16 cm mass in the excluded stomach remnant. Ultrasound-guided biopsy confirmed this mass to be a GIST. The patient was treated surgically with exploratory laparotomy with distal pancreatectomy, partial colectomy, partial gastrectomy, and splenectomy. There are currently only 3 known reported cases of GISTs after RYGB.