ENDOSCOPIC OBSERVATION METHOD AND COMPOSITION FOR IMPROVING DIAGNOSTIC PERFORMANCE INVOLVING APPLYING USEFUL WHITE OPAQUE SUBSTANCE TO DIAGNOSIS OF GASTRIC EPITHELIAL TUMORS (ADENOMA/GASTRIC CANCER)
[Problem] To develop a clinically useful composition and endoscopic observation method that utilize WOS properties. [Solution] A composition for improving diagnostic performance containing lipids as a constituent is characterized in that, by administering or loading said composition orally, by intubation or via endoscope, the lipids are absorbed by gastric tumors, facilitating the discovery of tumors and qualitative diagnoses by endoscope. Furthermore, an endoscopic observation method is characterized in that, by administering or loading the composition for improving diagnostic performance to a subject orally, by intubation or via endoscope, the lipids are absorbed by the subject's gastric tumor, facilitating the discovery of the tumor and qualitative diagnosis by endoscope. Tumors are thus whitened by administering or loading this composition for improving diagnostic performance prior to endoscopic observation, making it easier to discover and qualitatively diagnose tumors by endoscopic observation.