Retrospective Study
Copyright ©The Author(s) 2015.
World J Gastroenterol. Aug 14, 2015; 21(30): 9134-9141
Published online Aug 14, 2015. doi: 10.3748/wjg.v21.i30.9134
Figure 2
Figure 2 Study flow chart. CEA: Carcinoembryonic antigen.