title: Clinical significance of CDX2-positive circulating tumour cells in colorectal cancer patients.
abstract: BACKGROUND
  Our recent work has shown the feasibility of using a refined immunomagnetic enrichment (IE) assay to detect cytokeratin 20-positive circulating tumour cells (CK20 pCTCs) in colorectal cancer (CRC) patients. We attempted to improve the sensitivity for CRC by detecting another intestinal-type differentiation marker, CDX2 pCTCs, using the same methodology.
  
  
  METHODS
  CDX2 pCTCs were detected in patients with CRC, colorectal adenoma (CAD), benign colorectal diseases (BCD), other common cancers (OCC) and normal subjects (NS). Statistical analysis was used to correlate CDX2 pCTCs to the clinicohistopathological factors, recurrence, metastasis and survival after follow-up for 42 months in CRC patients.
  
  
  RESULTS
  CDX2 pCTCs were detected in 81% CRC patients (73 out of 90, median number=21.5 CTCs), 7.5% CAD patients (3 out of 40), 0% patients with BCD (0 out of 90), 2.5% patients with OCC (2 out of 80) and 0% NS (0 out of 40). Furthermore, statistical analysis showed that CDX2 pCTC numbers were associated with tumour- node-metastasis stage and lymph node status. Using the median CDX2 pCTC numbers as the cutoff points, stratified groups of CRC patients had significant differences in their recurrence and survival.
  
  
  CONCLUSIONS
  This study showed that the refined IE assay can detect CDX2 pCTCs with high sensitivity and that CDX2 pCTCs can generate clinically important information for CRC patients.
authors.affiliation: State Key Laboratory in Oncology in South China, Department of Clinical Oncology, Sir YK Pao Centre for Cancer, Hong Kong Cancer Institute and Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China. cesar01@netvigator.com
authors.forename: S C C
authors.initials: SC
authors.lastname: Wong
authors.forename: S S M
authors.initials: SS
authors.lastname: Ng
authors.forename: M T
authors.initials: MT
authors.lastname: Cheung
authors.forename: L Y
authors.initials: LY
authors.lastname: Luk
authors.forename: C M L
authors.initials: CM
authors.lastname: Chan
authors.forename: A H K
authors.initials: AH
authors.lastname: Cheung
authors.forename: V H M
authors.initials: VH
authors.lastname: Lee
authors.forename: P B S
authors.initials: PB
authors.lastname: Lai
authors.forename: B B Y
authors.initials: BB
authors.lastname: Ma
authors.forename: E P
authors.initials: EP
authors.lastname: Hui
authors.forename: M Y Y
authors.initials: MY
authors.lastname: Lam
authors.forename: T C C
authors.initials: TC
authors.lastname: Au
authors.forename: A T C
authors.initials: AT
authors.lastname: Chan
mesh_terms: D000236:Adenoma / Q000097:blood / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis / Q000378:metabolism; D000071616:CDX2 Transcription Factor; D002277:Carcinoma / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D015179:Colorectal Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D005260:Female; D018398:Homeodomain Proteins / Q000097:blood / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009360:Neoplastic Cells, Circulating / Q000378:metabolism* / Q000473:pathology*; D011379:Prognosis; D016019:Survival Analysis; D015534:Trans-Activators / Q000097:blood / Q000378:metabolism*; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D000071616:CDX2 Transcription Factor; D018398:Homeodomain Proteins; D015534:Trans-Activators