2769 Large Gastric Gastrointestinal Stromal Tumor With Spontaneous Rupture of Necrotic Fluid Collection

Abstract

INTRODUCTION: Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumor of the gastrointestinal tract. Fluid collection within GISTs is very rare with only several case reports documented. We present the first case of spontaneous rupture from a large gastric GIST with necrotic fluid collection which has been documented on endoscopic exam. CASE DESCRIPTION/METHODS: A 91 year-old Caucasian female with a 3 month history of weight loss and progressive dysphagia to solids presented for evaluation. She was afebrile and hemodynamically stable with mild tachycardia. Initial labs revealed mild leukocytosis and low protein/albumin. Computer tomography demonstrated large 12 × 11 cm gastric mass with air-fluid level. Follow-up diagnostic esophagogastroduodenoscopy (EGD) showed a large fundic mass with two large cratered ulcerations with bridging mass in the proximal stomach with unremarkable histology on biopsy. Follow-up EGD with endoscopic ultrasound (EUS) demonstrated similar visualization with now small collection of purulent fluid though no fistula was appreciated. On EUS there was a larger heterogeneous hypoechoic mass bridging across all echo layers and a fluid echogenicity without doppler flow contained within the mass. Fine needle aspiration showed spindle cell neoplasm (CD117 +, DOG1 +) compatible with GIST. Given comorbidity and advanced age, she was not considered a surgical candidate. After starting Imatinib, she was offered therapeutic EGD was for possible decompression of the fluid collection within the tumor, to relieve mass effect for palliation. On visual exam there was again evidence of more purulent material that was extruding from a small opening in the center of the mass. The endoscope was advanced into the small opening and revealed a large fluid filled cavity within the mass. After copious irrigation with suction the majority of the cystic fluid was removed and two plastic double pigtail stents were placed to allow full decompression of the cystic cavity. On follow-up exam, she reported improvement of her pain. DISCUSSION: GIST are most often found in the stomach but overall account for 3% of all gastric malignancies. The initial presentation is often asymptomatic but there are many cases of highly variable symptomatic presentations of larger GIST. GIST with cystic changes are considered rare, with only 11 cases reported to date. This case is the first documentation of a cystic GIST that spontaneously ruptured, forming a fistulous tract between the cavity and the stomach.