Case Report: A rare presentation of gastrointestinal amyloidosis: unmasking the hidden culprit of chronic epigastric pain and weight loss. - Veena, FNU; Akram, Muhammad Rizwan; Farag, Mohamed; Lajara Hallal, Priscilla; Shehi, Elona (Frontiers in Gastroenterology (Frontiers Media S.A.), 2026)