title: Carcinoembryonic antigen (CEA) level, CEA ratio, and treatment outcome of rectal cancer patients receiving pre-operative chemoradiation and surgery.
abstract: BACKGROUND
  To investigate serum carcinoembryonic antigen (CEA) as a prognostic factor for rectal cancer patients receiving pre-operative chemoradiotherapy (CRT).
  
  
  METHODS
  Between 2000 and 2009, 138 patients with advanced rectal cancer receiving CRT before surgery at our hospital were retrospectively classified into 3 groups: pre-CRT CEA <6 ng/ml (group L; n = 87); pre-CRT CEA ≥ 6 ng/ml and post-CRT CEA <6 ng/ml (group H-L; n = 32); and both pre- and post-CRT CEA ≥ 6 ng/ml (group H-H; n = 19). CEA ratio (defined as post-CRT CEA divided by pre-CRT CEA), post-CRT CEA level and other factors were reviewed for prediction of pathologic complete response (pCR).
  
  
  RESULTS
  Five-year disease-free survival (DFS) was better in groups L (69.0%) and H-L (74.5%) than in group H-H (44.9%) (p = 0.024). Pathologic complete response was observed in 19.5%, 21.9% and 5.3% of groups L, H-L and H-H respectively (p = 0.281). Multivariate analysis showed that ypN stage and pCR were independent prognostic factors for DFS and that post-CRT CEA level was independently predictive of pCR. As a whole, post-CRT CEA <2.61 ng/ml predicted pCR (sensitivity 76.0%; specificity 58.4%). For those with pre-CRT CEA ≥6 ng/ml, post-CRT CEA and CEA ratio both predicted pCR (sensitivity 87.5%, specificity 76.7%).
  
  
  CONCLUSIONS
  In patients with pre-CRT serum CEA ≥6 ng/ml, those with "normalized" CEA levels after CRT may have similar DFS to those with "normal" (<6 ng/ml) pre-CRT values. Post-CRT CEA level is a predictor for pCR, especially in those with pre-CRT CEA ≥6 ng/ml.
authors: Cancer Center, Taipei Veterans General Hospital, No, 201, Sec, 2, Shih-Pai Road, Taipei 112, Taiwan.
authors: Kai-Lin
authors: KL
authors: Yang
authors: Shung-Haur
authors: SH
authors: Yang
authors: Wen-Yih
authors: WY
authors: Liang
authors: Ying-Ju
authors: YJ
authors: Kuo
authors: Jen-Kou
authors: JK
authors: Lin
authors: Tzu-Chen
authors: TC
authors: Lin
authors: Wei-Shone
authors: WS
authors: Chen
authors: Jeng-Kae
authors: JK
authors: Jiang
authors: Huann-Sheng
authors: HS
authors: Wang
authors: Shih-Ching
authors: SC
authors: Chang
authors: Lee-Shing
authors: LS
authors: Chu
authors: Ling-Wei
authors: LW
authors: Wang
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000401:mortality / Q000628:therapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000097:blood*; D002272:Carcinoembryonic Antigen / Q000097:blood*; D059248:Chemoradiotherapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011300:Preoperative Care; D011379:Prognosis; D012004:Rectal Neoplasms / Q000097:blood / Q000401:mortality / Q000628:therapy*; D012074:Remission Induction; D012189:Retrospective Studies; D015996:Survival Rate; D005641:Tegafur / Q000008:administration & dosage; D014498:Uracil / Q000008:administration & dosage
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D005641:Tegafur; D014498:Uracil; D002955:Leucovorin