title: Telomerase activity is a prognostic factor for recurrence and survival in rectal cancer.
abstract: OBJECTIVE
  This study was designed to determine whether telomerase activity measured in samples of tumoral tissue, transitional mucosa, and normal mucosa from patients with sporadic colorectal cancer is a prognostic factor for recurrence and overall survival.
  
  
  METHODS
  Telomerase activity was determined by fluorescence-based telomeric repeat amplification in tissue samples from 108 patients with sporadic colorectal cancer. A telomerase index was determined by using the formula log (telomerase activity of cancer tissue - telomerase activity of normal mucosa).
  
  
  RESULTS
  Mean telomerase activity in tumoral tissue was 11.49 (total product generated), in transitional mucosa it was 1.51, and in normal mucosa it was 1.09 (P < 0.001). Telomerase activity and telomerase index were not correlated with clinicopathologic factors. Rectal cancer patients' recurrence-free survival was related to N classification (P = 0.004) and to tumor-node-metastases stage classification (P = 0.023) and telomerase index 0.85 (P = 0.023). Overall survival was associated with N classification (positive/negative) and telomerase index (</=0.85 or >0.85; P = 0.018 and P = 0.011, respectively).
  
  
  CONCLUSIONS
  Measurement of telomerase activity has a diagnostic value in colorectal patients. In rectal cancer, telomerase index is an independent prognostic factor for disease progression. A telomerase index</=0.85 and negative nodes can be used to predict disease progression.
authors.affiliation: Department of Medicine, Medical School, Lleida University, Lleida, Spain.
authors.forename: Cristina Valls
authors.initials: CV
authors.lastname: Bautista
authors.forename: Carme Piñol
authors.initials: CP
authors.lastname: Felis
authors.forename: Josep M Reñé
authors.initials: JM
authors.lastname: Espinet
authors.forename: Juan Buenestado
authors.initials: JB
authors.lastname: García
authors.forename: Joan Viñas
authors.initials: JV
authors.lastname: Salas
mesh_terms: D000368:Aged; D016009:Chi-Square Distribution; D015179:Colorectal Neoplasms / Q000201:enzymology* / Q000473:pathology / Q000601:surgery; D018450:Disease Progression; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000201:enzymology; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D016016:Proportional Hazards Models; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D019098:Telomerase / Q000378:metabolism*
chemical_list: D019098:Telomerase