title: Circulating tumor cells count predicts survival in colorectal cancer patients.
abstract: OBJECTIVE
  Data on the potential of circulating tumor cells (CTC) count in predicting overall survival (OS) in patients with colorectal cancer are timely and worthy of interest. This study aimed to evaluate the prognostic role of CTC count in both localized and metastatic colorectal cancer patients.
  
  
  METHODS
  Consecutive patients with histological diagnosis of colorectal cancer were enrolled. CTC count was performed, by using a quantitative immunofluorescence method, at baseline (T0) and 1 month following start of chemotherapy (T1). A CTC count <2 was considered negative, whilst a CTC level >/= 2 was positive. Overall survival was calculated accordingly.
  
  
  RESULTS
  A total of 75 colorectal cancer patients were enrolled, including 54 stages I-III and 21 stage IV patients. Overall, 21 (28%) patients had a positive CTC count at baseline, and it was significantly associated with a worse prognosis as compared to a negative status (OS: 36.2 vs. 61.6 months; P = 0.002). CTC count remained positive after chemotherapy in 22.4% of the patients and it was an independent prognostic factor of OS (P = 0.03; Hazard Ratio: 3.55; 95% CI: 1.1-11.5).
  
  
  CONCLUSIONS
  This study found that the presence of CTCs is associated with a reduced survival in colorectal cancer patients. Further studies aimed at testing such a predictive value in early stage colorectal cancer are awaited.
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy. adriana.romiti@tin.it.
authors.forename: Adriana
authors.initials: A
authors.lastname: Romiti
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Raffa
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Di Rocco
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Roberto
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Milano
authors.affiliation: Gastroenterology and Digestive Endoscopy, Nuovo Regina Margherita Hospital, Italy.
authors.forename: Angelo
authors.initials: A
authors.lastname: Zullo
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Leone
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Danilo
authors.initials: D
authors.lastname: Ranieri
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Mazzetta
authors.affiliation: Genetic Epidemiology Unit, National Centre for Epidemiology, Surveillance and Health Promotion, Istituto Superiore di Sanità, Italy.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Medda
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Ida
authors.initials: I
authors.lastname: Sarcina
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Viola
authors.initials: V
authors.lastname: Barucca
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: D'Antonio
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Durante
authors.affiliation: Surgical and Medical Department of Clinical Sciences, Biomedical Technologies and Translational Medicine Sant'Andrea Hospital Rome, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Ferri
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Torrisi
authors.affiliation: Clinical and Molecular Medicine Department, Sapienza University, Sant'Andrea Hospital, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Marchetti
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002452:Cell Count; D015179:Colorectal Neoplasms / Q000097:blood / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome