Department of General Surgery;
Peking Union Medical College Hospital;
Chinese Academy of Medical Sciences and Peking Union Medical College;
Beijing 100730;
China;
Clinical Immunology Center;
Chinese Academy of Medical Sciences and Peking Union Medical College;
Beijing 100730;
China;
Feasibility; minimally invasive pancreaticoduodenectomy; open pancreaticoduodenectomy; pancreatic head cancer; safety;