Endoscopic ultrasound-guided fine-needle aspiration was useful for definite diagnosis of advanced gastric cancer resembling a submucosal tumor. Report of a case

摘要

A 73-year-old man was referred to our hospital for further examination and treatment for hematemesis. Upper gastrointestinal endoscopy revealed a submucosal elevated lesion covered with normal mucosa on the posterior wall of the prepyloric region with pyloric ring stenosis. The pyloric ring was barely visible in the frontal view, but an endoscope could not pass through the pyloric ring. We were unable to detect erosions and ulcers. Histological examination of the specimen obtained from the pyloric region by forceps biopsy could not confirm malignancy. The tumor was detected by computed tomography (CT) as a low density area with ring-like enhancement on the gastric wall, and it was accompanied with multiple liver metastases. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was performed for the definite diagnosis. Histological examination of the biopsied specimen revealed adenocarcinoma. Subtotal gastrectomy was performed because the patient was unable to take by mouth. Histological examination of the resected specimen revealed moderately differentiated adenocarcinoma infiltrating into the serosa and forming a tumor with marked stromal fibrosis. The cancer cells were located mainly under the mucosa, and a small part of the tumor was exposed. Therefore, histological examination of the specimen obtained by forceps biopsy could not confirm malignancy. Histological diagnosis is critically important for determining the therapeutic strategy and for the patient to provide an informed consent. Our experience suggests that EUS-FNA was useful for the histological diagnosis of advanced gastric cancer resembling a submucosal tumor.