title: Pronounced tumour regression after radiotherapy is associated with negative/weak glucose transporter-1 expression in rectal cancer.
abstract: The aim of this study was to assess glucose transporter-1 (GLUT-1) expression as a predictor of disease outcome in rectal cancer treated by preoperative radio- or chemoradiotherapy.
  
  
  METHODS
  Operative samples from 175 rectal cancer patients and 78 preoperative biopsies were analysed for GLUT-1 expression using immunohistochemistry. Forty-six patients received long-course radiotherapy, with/without chemotherapy and tumour regression grade was analysed in these specimens.
  
  
  RESULTS
  Negative GLUT-1 expression was seen in 25/78 (32%) of the preoperative biopsies and in 38/78 (49%) of the operative samples. There was no significant correlation of GLUT-1 with common clinicopathological factors. A trend towards longer disease-free survival (DFS) for the long-course radiotherapy group patients was seen with negative/weak GLUT-1 staining intensity (p=0.066) and excellent tumour regression grade (p=0.068) in operative samples. Disease-free survival (p=0.068) and disease-specific survival (p=0.024) of the patients with excellent tumour regression were longer than among the patients with moderate or less regression.
  
  
  CONCLUSIONS
  A trend towards longer DFS among patients in favour of negative/weak GLUT-1 staining in the operative samples after long-course radiotherapy is demonstrated.
authors.affiliation: Department of Oncology and Radiotherapy, Turku University Hospital, Turku, Finland. eija.korkeila@tyks.fi
authors.forename: E
authors.initials: E
authors.lastname: Korkeila
authors.forename: P M
authors.initials: PM
authors.lastname: Jaakkola
authors.forename: K
authors.initials: K
authors.lastname: Syrjänen
authors.forename: S
authors.initials: S
authors.lastname: Pyrhönen
authors.forename: J
authors.initials: J
authors.lastname: Sundström
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D002288:Adenocarcinoma, Mucinous / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D051272:Glucose Transporter Type 1 / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D009367:Neoplasm Staging; D018714:Radiotherapy, Adjuvant; D012004:Rectal Neoplasms / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D051272:Glucose Transporter Type 1; C495677:SLC2A1 protein, human