[en] BACKGROUND: Positron emission tomography (PET) has been shown useful for the staging of patients with various carcinomas. METHODS: We have applied this technique to 54 cases of colorectal carcinoma and compared it to conventional imaging techniques. RESULTS: PET had moderately higher sensitivity and specificity than conventional techniques to detect individual lesion sites (75% vs 70.8% and 63% vs 21% respectively). It detected the same number of patients with recurrences (35/39) but overestimated disease less frequently (5 cases vs 12). PET favorably influenced therapeutic management in 17 patients, indicating different or additional surgery in 9 while avoiding surgery with curative intent or unnecessary surgery in 8. In 5 cases, erroneous information provided by PET could be corrected by conventional imaging techniques. CONCLUSION: We conclude that PET appears to provide complementary information useful for staging patients with colorectal carcinomas. It can significantly modify patients management. These data should be confirmed by a prospective study.