Synchronous Ampullary Adenocarcinoma and Renal Cell Carcinoma: A Rare Case Report and Literature Review. - Hoang, Thang Manh; Bui, Noi Xuan; Nghiem, Viet Xuan; Nguyen, Tung Van; Phan, Linh Van; Nguyen, Vinh Ngoc (Case Reports in Oncology, 2026)