CREB1 and digestive system neoplasm: We examined specific gene rearrangements including Ewing sarcoma breakpoint region 1 (EWSR1), EWSR‐1 activating factor 1 (ATF1), and cAMP response element‐binding protein (CREB1) of the tumors to eliminate a possibility of clear cell sarcoma (CCS) and clear cell sarcoma‐like gastrointestinal tumor (CCSLGT).