title: Normalization of CEA Levels Post-Neoadjuvant Therapy is a Strong Predictor of Pathologic Complete Response in Rectal Cancer.
abstract: BACKGROUND
  Recent attention has been focused on the relationship between carcinoembryonic antigen (CEA) and pathological complete response (pCR), without consensus regarding its predictive value. This study aims to examine the association between CEA and pCR.
  
  
  METHODS
  We conducted a retrospective review of a prospectively maintained database of all patients who underwent primary rectal cancer resection after neo-adjuvant chemoradiotherapy (nCRT). Patients were divided into two groups, pCR or no-pCR, based on final pathology. CEA levels were measured at the initial visit with the surgeon/oncologist and post-completion of nCRT.
  
  
  RESULTS
  One hundred and forty-one patients underwent primary rectal cancer resections after nCRT. Nineteen patients (13.5 %) achieved pCR, while 122 (86.5 %) had no-pCR. Pre-nCRT CEA levels were not significantly different between groups (2.75 vs 4.5 μg/L, p = 0.65). However, post-nCRT CEA levels were significantly lower in patients with pCR (1.7 vs 2.4 μg/L, p < 0.01). On multivariate logistic regression analyses, low post-nCRT CEA level was an independent predictor of pCR (OR 1.74, CI 1.06, 3.81) and normalization of CEA from an initially elevated level was a highly significant predictor of pCR (OR 64.8, CI 2.53, 18,371).
  
  
  CONCLUSIONS
  Low post-nCRT CEA is an independent predictor of pCR, and normalization of CEA post-nCRT is a strong predictor of pCR.
authors: Division of Colorectal Surgery, Jewish General Hospital, Montreal, QC, Canada.
authors: Ariella
authors: A
authors: Kleiman
authors: Ahmed
authors: A
authors: Al-Khamis
authors: Ali
authors: A
authors: Farsi
authors: Abbas
authors: A
authors: Kezouh
authors: Te
authors: T
authors: Vuong
authors: Philip H
authors: PH
authors: Gordon
authors: Carol-Ann
authors: CA
authors: Vasilevsky
authors: Nancy
authors: N
authors: Morin
authors: Julio
authors: J
authors: Faria
authors: Gabriela
authors: G
authors: Ghitulescu
authors: Marylise
authors: M
authors: Boutros
mesh_terms: D000230:Adenocarcinoma / Q000097:blood* / Q000473:pathology / Q000628:therapy; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood; D002272:Carcinoembryonic Antigen / Q000097:blood*; D059186:Chemoradiotherapy, Adjuvant; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012004:Rectal Neoplasms / Q000097:blood* / Q000473:pathology / Q000628:therapy; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen