It was suspected that a 75-year-old woman had advanced infiltrative gastric cancer. However, endoscopic forceps biopsy specimens did not reveal adenocarcinoma.

She was referred to our institute for further examination and treatment. To obtain sufficient submucosal specimens, underwater EMR was performed. Histological examination of 3 of the 6 specimens revealed a poorly differentiated adenocarcinoma in the deep lamina propria and submucosa. Laparoscopy histologically confirmed peritoneal dissemination, and chemotherapy was performed.

The underwater EMR technique enables resection of sufficient deep submucosal tissue, yielding a high en bloc resection rate for colorectal polyps. EUS-guided FNA is often performed to acquire deep submucosal tissue for diagnosis when neoplastic tissues exist beyond the mucosa, and pathological diagnosis using endoscopic forceps biopsy is difficult.

With the use of EUS-guided FNA for both the gastric wall and lymph nodes, overall diagnostic yield could reach 87.5% to 93.7%, but EUS-guided FNA poses a certain risk of seeding. In this case, no enlarged lymph nodes were detected on a CT scan. Thus, we performed underwater EMR instead of EUS-guided FNA.

Conventional EMR has reportedly been shown to be useful for diagnosing infiltrative gastric cancer. However, needle injection for a lift into the hard tumor tissue is often difficult, and inappropriate injection makes subsequent snaring of the tissue challenging. Using underwater EMR, adequate submucosal tissue could be obtained without needle injection, providing an accurate pathological diagnosis.

This video will help readers understand the usefulness of underwater EMR for infiltrative gastric cancer. 

Abnormally thickened folds with poor extension of the gastric body.