Coexistence of gastrointestinal stromal tumor (GIST) and colorectal adenocarcinoma: A case report oleh Evangelos Felekouras, Sotirios Georgopoulos, Frangisca Sigala, Alexandros Papalambros, Papaconstantinou Ioannis, Athanasios Petrou, Efstathios Papalambros, Athanasios Giannopoulos