ASO Author Reflections: Unexpected Intraoperative Positive Ductal Margin in Pancreaticoduodenectomy for Distal Cholangiocarcinoma: Is Hepatopancreatoduodenectomy Always Necessary? - Umino R; Esaki M; Mizui T; Miyata A; Nara S; Hiraoka N (Annals of surgical oncology, 2026)