US QUIZ MARCH 2021
Case Report A 48-year-old asymptomatic female underwent an abdominal ultrasound due to liver enzymes elevation (AST 45 U/L, ALT 77 U/L) detected on routine evaluation. Abdominal ultrasound revealed an incidental gastric wall lesion that was misinterpreted as A cyst of the pancreatic body measuring 68x45mm. Additional abdominal computed tomography (CT) was performed showing a well-defined, hypodense gastric mass with calcifications, measuring 65mm, on the posterior wall of the distal body, compressing the transverse colon; no lesions were visible on the pancreas or liver. Upper gastrointestinal endoscopy demonstrated a 6cm rounded subepithelial lesion (SEL), with a central depression, on the posterior face of the distal body of the stomach (Fig. 1). On the endoscopic ultrasound (EUS) examination, the gastric lesion corresponded to a well-defined heterogeneous lesion, with solid iso/hypoechoic areas, necrotic/cystic (anechoic) areas and calcifications, located on the fourth layer (muscularis propria) (Fig. 2). Additionally, rounded and hypoechoic perilesional lymph nodes (maximum diameter 14mm) were identified. EUS-guided fine needle biopsy (FNB) using a 22G needle was performed (two needle passes; AcquireTM Endoscopic Ultrasound FNB Device, Boston Scientific) and the histopathological analyses revealed rare spindle cell tissue fragments, with a fascicular arrangement, without nuclear atypia nor mitosis. Immunohistochemistry staining was positive to S100 and negative to CD117, CD34, DOG 1 and smooth muscle actine (Fig. 3A and 3B). Quiz Discussion The histopathological features and immunohistochemical staining pattern were consistent with the diagnosis of gastric schwannoma. After multidisciplinary discussion, the patient was submitted to a laparoscopic partial gastrectomy with Roux-en-Y reconstruction, and the histopathological examination of […]