Management of local recurrence of colorectal cancer: the role of PET/CT

Abstract

The aim was to examine the clinical applicability of positron-emission tomography/computed tomography (PET/CT) for diagnosing local recurrence of colorectal cancer. From August 2003 to August 2008, 256 patients with colorectal cancer underwent PET/CT scanning for staging or restaging. Local recurrence was detected in 22 patients (18 men, 4 women) postsurgically. Of the 22 patients, 21 (95.5%) underwent positive 2-[fluorine-18]-fluoro-2-deoxy-D: -glucose uptake and were diagnosed with local recurrence by PET/CT; the results were negative in one case (4.5%). The sensitivity, specificity, positive predictive value, and negative predictive value for local recurrence were 95.5%, 100%, 100%, and 99.6%, respectively. CT/MRI scans yielded the following results: positive, 10 cases (45.5%); suspected positive, 11 cases (50.0%); negative, 1 case (4.5%). In the suspected positive cases, not only imaging but also colonoscopy and tumor markers among other techniques were used for definitive diagnosis. PET/CT has high sensitivity and specificity for diagnosing local recurrence of colorectal cancer and would be useful especially in the case of locally recurrent colorectal cancer suspected to be positive by CT/MRI.