GOALS: Tumour hypoxia has been shown to be a predictor of early distant relapse in node-negative breast and cervical cancer. The purpose of the present study was to determine the role of hypoxia in predicting patients who are at high risk of disease recurrence in Dukes B colorectal cancers. MATERIALS AND METHODS: Archival tissue was retrieved from 52 patients who had undergone surgical resection for primary colorectal cancer. Tissue micro-arrays were constructed using tissue from the margin and the centre of the tumour. Hypoxia markers hypoxia-inducible factor (Hif)-1alpha, vascular endothelial growth factor (VEGF), carbonic anhydrase (CA)-9 and glucose transporter (Glut)-1 were visualised using immunohistochemical detection and quantified using semi-quantitative analysis of the digitised images. Clinical details and outcome data were retrieved by case note review and collated with hypoxia markers data in a statistical database. RESULTS: Primary colorectal cancers with a high Hif-1alpha expression tended to have a significantly worse disease-free survival (log rank p