Selective Use of 18F-Fluorodeoxyglucose-Positron Emission Tomography and Computed Tomography in the Management of Metastatic Disease from Colorectal Cancer : Results from a regional centre

Abstract

Objectives: Computed tomography (CT) scans are routinely used for primary staging and disease surveillance in patients with colorectal cancer. However, these scans have limited sensitivity in some organs and can only detect lesions with morphological changes, whereas ¹⁸F-fluorodeoxyglucose-positron emission tomography (¹⁸F-FDG-PET) scans are able to detect areas of metabolic change before morphological changes appear. The aim of this study was to evaluate the impact of ¹⁸F-FDG-PET/CT scans over conventional imaging during preoperative work-ups or follow-ups in a selected group of patients. Methods: This retrospective cohort study, which took place between July 2009 and May 2011, assessed 1,043 patient records from the South East Scotland Cancer Network colorectal cancer database. A total of 102 patients who underwent ¹⁸F-FDG-PET/CT scans in addition to conventional imaging were included in the study. These patients had potentially resectable metastases, equivocal findings on CT scans and elevated carcinoembryonic antigen levels with negative conventional imaging. Results: Of the 102 patients included in the study, 22 underwent a preoperative ¹⁸F-FDG-PET/CT scan and 80 underwent a follow-up ¹⁸F-FDG-PET/CT scan. In the preoperative scan group, the ¹⁸F-FDG-PET/CT scan had a major impact on 16 patients (72.75%) and no impact on six patients (27.25%). In the follow-up scan group, the ¹⁸F-FDG-PET/CT scan had a major impact on 51 (63.75%), a minor impact on four (5%), no impact on 22 (27.5%) and a negative impact on three (3.75%) patients. Conclusion: The results of this study demonstrated that ¹⁸F-FDGPET/ CT scans have a considerable effect on disease management when undertaken among indicated colorectal cancer patients.