title: Clinical significance of serial serum carcinoembryonic antigen values for treating rectal cancer with preoperative chemoradiotherapy.
abstract: OBJECTIVE
  Preoperative chemoradiotherapy is now widely accepted to treat rectal cancer; however, the prognosis for rectal cancer patients during and after chemoradiotherapy must be determined. The aim of this study was to evaluate the serial serum carcinoembryonic antigen (s-CEA) samples in patients with rectal cancer who underwent radical surgery after concurrent chemoradiotherapy (CRT).
  
  
  METHODS
  This study evaluated 236 patients with rectal cancer who received preoperative CRT followed by curative surgery between June 2005 and June 2010. We measured the patient's s-CEA levels pre-CRT, post-CRT and post-surgery. Patients were classified into four groups according to their s-CEA concentrations (group 1, high, high, high; group 2, high, high, normal; group 3, high, normal, normal; group 4, normal, normal, normal). We analyzed the clinicopathologic factors and the outcomes among these groups.
  
  
  RESULTS
  Of the 236 patients, 12 were in group 1, 31 were in group 2, 67 were in group 3, and 126 were in group 4. The 3-year disease-free survival rate in group 1 was poorer than those in group 3 (P = 0.007) and group 4 (P < 0.001). In a univariate analysis, type of surgery, clinical N stage, pathologic T or N stage, lymphovascular invasion, perineural invasion, and CEA group were prognostic factors. A multivariate analysis revealed that type of surgery, pathologic T stage, and lymphovascular invasion were independent prognostic factors; however, no statistical significance was associated with the CEA group.
  
  
  CONCLUSIONS
  High pre-CRT, post-CRT, and post-surgery s-CEA levels in patients with rectal cancer were associated with high rates of systemic recurrence and poor survival. Therefore, patients with sustained high s-CEA levels during CRT require careful monitoring after surgery.
authors.affiliation: Division of Colorectal Surgery, Department of Surgery, Chonnam National University Medical School, Gwangju, Korea.
authors.forename: Young Jae
authors.initials: YJ
authors.lastname: Ryu
authors.forename: Chang Hyun
authors.initials: CH
authors.lastname: Kim
authors.forename: Hun Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Hyo
authors.initials: H
authors.lastname: Kang
authors.forename: Sang Woo
authors.initials: SW
authors.lastname: Lim
authors.forename: Jung Wook
authors.initials: JW
authors.lastname: Huh
authors.forename: Jae Kyun
authors.initials: JK
authors.lastname: Ju
authors.forename: Young Jin
authors.initials: YJ
authors.lastname: Kim
authors.forename: Hyeong Rok
authors.initials: HR
authors.lastname: Kim