Prognostic value of changes in serum carcinoembryonic antigen levels for preoperative chemoradiotherapy response in locally advanced rectal cancer

Figure 1 Survival in study groups according to pre- and post-chemoradiotherapy serum levels of carcinoembryonic antigen. A: Five-year disease-free survival in the groups according to pre- and post-chemoradiotherapy (CRT) serum carcinoembryonic antigen (CEA) levels (Group A vs Group B vs Group C; P = 0.145); and B: Five-year overall survival in the groups according to pre- and post-CRT serum CEA levels (Group A vs Group B vs Group C; P = 0.005). Group A: patients with pre- and post-CRT CEA levels > 5 ng/mL; Group B: Patients with pre- and post-CRT CEA levels > 5 and ≤ 5 ng/mL, respectively; and Group C: Patients with pre- and post-CRT CEA levels < 5 ng/mL.