Efficacy of 6‐mm diameter fully covered self‐expandable metallic stents in preoperative biliary drainage for pancreatic ductal adenocarcinoma oleh Fumiya Kataoka, Dai Inoue, Masato Watanabe, Keita Fukuda, Tsubasa Nobusawa, Kayo Umemura, Natsuki Miura, Takuya Yokota, Astushi Yoshioka, Kohei Shimoji, Ayano Nakazono, Hideyuki Horike, Yuki Ogura, Tatsuya Hayashi, Yasuhiro Morita, Shin Namiki