Clinical importance of serum CEA and CA-19-9 levels in oesophagogastric junction adenocarcinomas - Sert, Ozlem; Bozkurt, Hilmi; Olmez, Tolga; Aray, Emre; Uzun, Orhan; Gulmez, Selcuk; Senger, Aziz; Duman, Mustafa; Polat, Erdal (Gastroenterology Review/Przegląd Gastroenterologiczny, 2021)