Magnifying pharmacoendoscopy: response of microvessels to epinephrine stimulation in differentiated early gastric cancers

BackgroundMagnifying endoscopy is a promising modality for fine observation of minute surface structures and microvessel architecture in gastric lesions.ObjectiveTo observe the response of microvessels to epinephrine stimulation in early gastric cancer tissues and to assess the usefulness of magnifying pharmacoendoscopy for histologic diagnosis.DesignThis was a prospective pilot study.SettingThis study was conducted at an academic hospital.PatientsTwenty-nine patients with differentiated early gastric cancer were enrolled.InterventionsMicrovessels in both the cancerous lesion and its adjacent non-neoplastic gastric mucosa were observed by magnifying endoscopy before and after focal spray with epinephrine solution (0.05 mg/mL).Main Outcome Measurements and ResultsAfter epinephrine stimulation, noncancerous gastric mucosa surrounding the cancerous lesion showed a change in color from red to white; no microvessels were evident. On the other hand, all the cancerous lesions examined clearly showed enhancement of tumor microvessels. The rate of detection of tumor microvessels by magnifying pharmacoendoscopy (100%) was significantly higher than that by magnifying endoscopy alone (41.3%).LimitationsThis was small pilot study.ConclusionsMagnifying pharmacoendoscopy with epinephrine is a powerful tool for assessing tumor vascularity and may contribute to the histologic diagnosis of differentiated early gastric cancers before endoscopic treatment.