An Unusual Presentation of a Pediatric Gastrointestinal Stromal Tumor (GIST) - Abstract
Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors of the gastrointestinal tract. They are rarely seen in children, and the majority of cases occur in the stomach. We report the case of a 17 years old male with a duodenal GIST. He presented with the sole symptom of acute onset fatigue and shortness of breath and on admission was found to have a severe microcytic anemia. An upper endoscopy was performed and a polypoid mass with an adherent clot was identified in the duodenum. No obvious stalk was seen and a biopsy of the mass was taken. Histological findings of the biopsy revealed a spindle cell GIST positive for C-KIT (CD117), a type III tyrosine kinase receptor. Ten days after his admission, the tumor was resected. The mitotic rate was 9/ 50 HPF with negative margins which conferred an intermediate risk according to the NIH consensus. C-KIT positivity was confirmed. Mutation analysis was performed and was positive for mutation in KIT gene exon 11. No mutation was detected in the PDGFRA exons. Typically, gastric GIST is described on endoscopy as a submucosal mass with smooth margins and a normal overlying mucosa. Endoscopic biopsies are often reported as nondiagnostic. In this case, the mass was polypoid and friable in appearance and was suspicious for a polyposis syndrome. This case substantiates the importance of including GIST in the differential diagnosis of a duodenal polypoid mass on endoscopy. Furthermore, it demonstrates the usefulness of endoscopic biopsy in confirming the diagnosis, which can help in the surgical management of these patients.