title: Combined preoperative CEA and CD44v6 improves prognostic value in patients with stage I and stage II colorectal cancer.
abstract: OBJECTIVE
  Combination of biomarkers may improve diagnosis and have better prognostic value than single markers. The purpose of this study was to investigate whether combined CEA and CD44v6 improves prognostic value in stage I and stage II (stage I/II) colorectal cancer (CRC).
  
  
  METHODS
  Preoperative serum CEA level and the expression of CD44v6 in CRC tissues were examined by electrochemiluminescence immunoassay and immunohistochemistry, respectively. The association of CEA and CD44v6 with clinicopathological features and their possible prognostic values was analyzed.
  
  
  RESULTS
  The preoperative elevated serum CEA level and positive CD44v6 expression were detected in 30.1 % (52/173) serum samples and 60.5 % (101/167) CRC tissues, respectively. Patients with an elevated-CEA level or a CD44v6-negative tumor had a worse disease-specific survival (DSS) than those with a normal-CEA level or CD44v6-positive tumor (P = 0.024, P = 0.012, respectively). Moreover, CD44v6 expression could be used in discriminating patients from good to poor prognosis in normal-CEA subgroup (P = 0.043), but not in elevated-CEA subgroup (P = 0.563). Multivariate analysis revealed that combined CEA and CD44v6 was an independent prognostic factor for patients with stage I/II CRC (P = 0.023). However, serum CEA level only retained a borderline significance for correlation with a worse DSS (P = 0.059), and CD44v6 expression alone was not an independent prognostic factor for DSS in multivariate analysis (P = 0.123).
  
  
  CONCLUSIONS
  These results suggested that combined CEA/CD44v6 had better prognostic value than CEA or CD44v6 alone for patients with stage I/II CRC.
authors.affiliation: Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Minimally Invasive Gastrointestinal Surgery, Peking University Cancer Hospital & Institute, 52 Fucheng Road, Haidian District, Beijing, 100142, China.
authors.forename: L
authors.initials: L
authors.lastname: Chen
authors.forename: B
authors.initials: B
authors.lastname: Jiang
authors.forename: Z
authors.initials: Z
authors.lastname: Wang
authors.forename: M
authors.initials: M
authors.lastname: Liu
authors.forename: H
authors.initials: H
authors.lastname: Yang
authors.forename: J
authors.initials: J
authors.lastname: Xing
authors.forename: C
authors.initials: C
authors.lastname: Zhang
authors.forename: Z
authors.initials: Z
authors.lastname: Yao
authors.forename: N
authors.initials: N
authors.lastname: Zhang
authors.forename: M
authors.initials: M
authors.lastname: Cui
authors.forename: X
authors.initials: X
authors.lastname: Su
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D002272:Carcinoembryonic Antigen / Q000032:analysis* / Q000096:biosynthesis; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D005260:Female; D006801:Humans; D018960:Hyaluronan Receptors / Q000032:analysis* / Q000096:biosynthesis; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models
chemical_list: D014408:Biomarkers, Tumor; C112697:CD44v6 antigen; D002272:Carcinoembryonic Antigen; D018960:Hyaluronan Receptors