title: Role of circulating tumour cells in predicting recurrence after excision of primary colorectal carcinoma.
abstract: BACKGROUND
  This study assessed the potential for reverse transcriptase-polymerase chain reaction (RT-PCR)-based circulating tumour cell identification to predict colorectal cancer recurrence.
  
  
  METHODS
  mRNA for carcinoembryonic antigen and cytokeratin 20 was identified by RT-PCR in blood from patients with colorectal cancer, before and after primary tumour resection. Cancer recurrence was assessed at follow-up, and the accuracy of RT-PCR and primary tumour lymph node positivity in predicting recurrence was estimated.
  
  
  RESULTS
  One hundred and ninety-six patients with colorectal cancer were studied over a median follow-up of 1393 days from surgery. Regression analysis selected 24-h post-resection RT-PCR positivity (hazard ratio for a positive test in predicting recurrence 8.66 (95 per cent confidence interval (c.i.) 3.08 to 24.33)) before lymph node involvement (hazard ratio 7.92 (95 per cent c.i. 3.26 to 19.20)). When 24-h post-resection RT-PCR was combined with lymph node positivity, the hazard ratio increased to 18.54 (95 per cent c.i. 4.01 to 85.11), attributing a 3 per cent recurrence risk to 52 per cent, and a 50 per cent recurrence risk to 48 per cent, of patients with colorectal cancer resected with curative intent.
  
  
  CONCLUSIONS
  RT-PCR positivity within 24 h of primary colorectal cancer resection is a strong predictor of colorectal cancer recurrence, and may be useful clinically.
authors.affiliation: Division of Surgery, Oncology, Reproduction and Anaesthesia, Faculty of Medicine, Imperial College, Chelsea and Westminster Hospital, London, UK. t.allenmersh@imperial.ac.uk
authors.forename: T G
authors.initials: TG
authors.lastname: Allen-Mersh
authors.forename: T K
authors.initials: TK
authors.lastname: McCullough
authors.forename: H
authors.initials: H
authors.lastname: Patel
authors.forename: R Q
authors.initials: RQ
authors.lastname: Wharton
authors.forename: C
authors.initials: C
authors.lastname: Glover
authors.forename: S K
authors.initials: SK
authors.lastname: Jonas
mesh_terms: D000368:Aged; D002272:Carcinoembryonic Antigen / Q000097:blood* / Q000235:genetics; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053554:Keratin-20 / Q000097:blood* / Q000235:genetics; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D009360:Neoplastic Cells, Circulating; D011237:Predictive Value of Tests; D012333:RNA, Messenger / Q000097:blood; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012307:Risk Factors
chemical_list: D002272:Carcinoembryonic Antigen; D053554:Keratin-20; D012333:RNA, Messenger