Diagnosis of the extent of gastric cancers by a new endoscopic ultrasonic tactile sensor.

BACKGROUND Because gastrointestinal cancers are generally firm, the presence and extent of a tumor can be assessed by touch during surgery. However, an objective scale for evaluating tissue hardness does not exist. We developed a new instrument, the endoscopic ultrasonic tactile sensor, that allows objective evaluation of hardness. In this study the usefulness of this device for diagnosis of the extent of gastric cancers was evaluated. METHODS Twenty-three patients with depressed or ulcerated early gastric cancers and 7 patients with active or healed gastric ulcers underwent endoscopic examination with the ultrasonic tactile sensor before gastrectomy. RESULTS Gastric cancers were significantly harder than normal mucosa or gastric ulcers. The histologic type of gastric cancer and the presence of ulceration did not affect tumor hardness and mucosal cancers could not be differentiated from submucosal or deeper cancers. CONCLUSIONS This new ultrasonic tactile sensor was useful for endoscopic diagnosis of the extent of gastric cancers.