PROBLEM TO BE SOLVED: To provide a similar case retrieval device capable of retrieving a similar case by paying attention to respective feature amounts of plural interest areas.SOLUTION: A similar case retrieval server 17 comprises: a feature amount calculation part 62； an individual similarity calculation part 65； and a similar case retrieval part 67. The feature amount calculation part 62 acquires a feature amount for every interest area ROI, related to plural interest areas ROI which are designated by inspection data 21 including one or more inspection images 19 and designated to include object lesions OL which are lesions existing in the inspection images 19, and respectively include one or more different object lesions OL. The individual similarity calculation part 65 compares the feature amount for every interest area ROI and a feature amount of a case lesion CL which is a lesion in a case image 22 registered in the case, and calculates individual similarity for every interest area ROI. The similar case retrieval part 67 retrieves similar case based on the calculated plural pieces of individual similarity.【課題】複数の関心領域のそれぞれの特徴量に着目した類似症例検索が可能な類似症例検索装置を提供する。【解決手段】 類似症例検索サーバ１７は、特徴量算出部６２、個別類似度算出部６５、類似症例検索部６７を備える。特徴量算出部６２は、検査画像１９を１枚以上含む検査データ２１において指定され、検査画像１９内に存在する病変である対象病変ＯＬを含むように指定される関心領域ＲＯＩであり、異なる対象病変ＯＬをそれぞれ１つ以上含む複数の関心領域ＲＯＩに関して、関心領域ＲＯＩ毎の特徴量を取得する。個別類似度算出部６５は、関心領域ＲＯＩ毎の特徴量と、症例に登録された、症例画像２２内の病変である症例病変ＣＬの特徴量とを比較して、関心領域ＲＯＩ毎の個別類似度を算出する。類似症例検索部６７は、算出した複数の個別類似度に基づいて、類似症例を検索する。【選択図】図１１
