On a display processing apparatus, on a case data selection screen, display call buttons for respectively instructing the display of the case data selection screen, a listing display of red color detection bars, a listing display of average color bars, a listing display of thumbnails extracted as observation targets, a digest listing display of thumbnails extracted from a database based on a predetermined reference, and a diagnostic report are displayed at the bottom of the screen in addition to the display of a case data listing display window in which a case data number in a case data number field, and data such as the name and the ID of a patient, an examination date, etc. in an identification data field are displayed to be scrollable.