title: Relationship among circulating tumor cells, CEA and overall survival in patients with metastatic colorectal cancer.
abstract: BACKGROUND
  We previously reported results of a prospective trial evaluating the significance of circulating tumor cells (CTCs) in patients with metastatic colorectal cancer (mCRC). This secondary analysis assessed the relationship of the CTC number with carcinoembryonic antigen (CEA) and overall survival.
  
  
  METHODS
  Patients with mCRC had CTCs measured at baseline and specific time points after the initiation of new therapy. Patients with a baseline CEA value ≥ 10 ng/ml and CEA measurements within ± 30 days of the CTC collection were included.
  
  
  RESULTS
  We included 217 patients with mCRC who had a CEA value of ≥ 10 ng/ml. Increased baseline CEA was associated with shorter survival (15.8 versus 20.7 months, P = 0.012). Among all patients with a baseline CEA value of ≥ 25 ng/ml, patients with low baseline CTCs (<3, n = 99) had longer survival than those with high CTCs (≥ 3, n = 58; 20.8 versus 11.7 months, P = 0.001). CTCs added prognostic information at the 3-5- and 6-12-week time points regardless of CEA. In a multivariate analysis, CTCs at baseline but not CEA independently predicted survival and both CTCs and CEA independently predicted survival at 6-12 weeks.
  
  
  CONCLUSIONS
  This study demonstrates that both CEA and CTCs contribute prognostic information for patients with mCRC.
authors.affiliation: Department of Medicine, Division of Hematology-Oncology, University of Pennsylvania, Philadelphia. Electronic address: charu.aggarwal@uphs.upenn.edu.
authors.forename: C
authors.initials: C
authors.lastname: Aggarwal
authors.affiliation: Department of Medicine, Division of Hematology-Oncology, Case Western Reserve University, Cleveland, USA.
authors.forename: N J
authors.initials: NJ
authors.lastname: Meropol
authors.affiliation: Department of Medical Oncology, Academic Medical Center, University of Amsterdam, The Netherlands.
authors.forename: C J
authors.initials: CJ
authors.lastname: Punt
authors.affiliation: Hematology Oncology Associates, Port Saint Lucie.
authors.forename: N
authors.initials: N
authors.lastname: Iannotti
authors.affiliation: Medical Oncology Associates, Kingston.
authors.forename: B H
authors.initials: BH
authors.lastname: Saidman
authors.affiliation: Medical Oncology and Hematology, PC, New Haven.
authors.forename: K D
authors.initials: KD
authors.lastname: Sabbath
authors.affiliation: Union Hospital, Canton.
authors.forename: N Y
authors.initials: NY
authors.lastname: Gabrail
authors.affiliation: Department of Medical Oncology, Washington University, St Louis.
authors.forename: J
authors.initials: J
authors.lastname: Picus
authors.affiliation: Department of Medical Oncology, Duke University Medical Center, Durham.
authors.forename: M A
authors.initials: MA
authors.lastname: Morse
authors.affiliation: Department of Medicine, Division of Hematology-Oncology, Thomas Jefferson University, Philadelphia.
authors.forename: E
authors.initials: E
authors.lastname: Mitchell
authors.affiliation: Veridex, LLC, Raritan.
authors.forename: M C
authors.initials: MC
authors.lastname: Miller
authors.affiliation: Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Cohen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood; D002272:Carcinoembryonic Antigen / Q000097:blood*; D015179:Colorectal Neoplasms / Q000097:blood / Q000188:drug therapy / Q000401:mortality; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009360:Neoplastic Cells, Circulating; D011379:Prognosis; D013534:Survival; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen