Metastatic Esophageal Gastrointestinal Stromal Tumor (GIST) in a Patient with Dysphagia: A Case Report

Abstract

Purpose: Gastrointestinal stromal tumors (GISTs) have been definitively defined since 1998 with the advent of immunohistochemical staining with CD117. While most commonly seen in the stomach (60-70%), GISTs can be found as small incidental lesions in the esophagus (≤1%), and very rarely as large symptomatic lesions. A 64-year-old male presented to the ER with chest pain for 2 days. His medical history was significant for coronary artery disease, status-post stent placement 1 year ago. On review of symptoms he admitted to progressively worsening dysphagia to solids, then liquids, for 3 months with an associated 15lb. weight loss. His social history was positive for a 42-year pack history. In the ER, the patient also complained of RUQ pain for a few weeks, which prompted a Computed Tomography (CT) of the abdomen and pelvis. The CT scan revealed multiple hypodense areas seen within the left lobe of the liver, concerning for neoplasm. Notable laboratory results on admission revealed an iron deficient microcytic anemia (Hemoglobin-8.7 g/dL, MCV-64fL, Iron-22 μg/dL). He was admitted to the medical floor for further workup and GI was consulted. Esophagogastroduodenoscopy (EGD) revealed a large submucosal tumor measuring ˜10cm in length, which occupied ˜90% of the circumference of the distal esophagus and extended into the cardia of the stomach. While the tumor was not noted to be bleeding, it was ulcerated and friable. The remainder of the exam was normal. Pathologic examination of the biopsies revealed a single cellular focus of spindle cells, with immunohistochemical staining strongly positive for CD117, supporting a diagnosis of GIST. Subsequent CT guided biopsy of a liver lesion was also positive for spindle cells with a similar profile. While rare (≤1%), esophageal GISTs can be found incidentally on EGD as small lesions. Rarer still, they can present as large symptomatic lesions that have already metastasized, as was the case with our patient.Figure: [574] Retroflexed view of esophageal GIST protruding into the cardia.