The relationship between aortoiliac calcification and long-term outcome in rectal cancer resection.

705Background: The interaction between host and tumour factors is an important determinant of long-term outcome following rectal cancer resection. At cellular level, hypoxia within the tumour microenvironment stimulates neovascularisation, alters tumour metabolism and is implicated in dissemination and metastases. At host level, restricted blood flow to the tumour may play a role in tumour hypoxia. Significant calcification of the distal aortic and iliac arteries could result in impaired rectal perfusion. We aimed to investigate the relationship between aortoiliac calcification (AC) and long-term outcome following rectal cancer resection. Methods: Patients were identified from a prospectively maintained database. Recurrence and survival data were abstracted. On staging CT images, the sum of calcified quadrants of the distal aorta and iliac arteries at the level of the bifurcation was calculated. ROC analysis was used to identify the optimum threshold for determining significant calcification. Results: Bet...