Post-Operative Follow-up of Colorectal Cancer: Computed Tomography or F-18 Positron Emission Computed Tomography? That is the Question

Abstract
Backgroud: In Egypt, the Colorectal cancer is considered the 7th commonest cancer, local recurrence, distant metastasis or both occurs in 30-50% of patients after operations. Both Computed Tomography (CT) and Positron Emission Tomog-raphy (PET) are well established in the diagnosis of Colorectal Cancer Recurrence (CRCR).
Aim of Study: In this study, we aimed to evaluate the diagnostic performance of 18F-FDG PET/CT in postoperative follow-up of CRC patients and the detection of local recurrence and distant metastasis as compared with CT.
Patients and Methods: 62 post-operative patients with colorectal carcinoma underwent whole body FDG PET/CT. The final histopathological and formal clinical follow-up findings were used as gold standard to determine the sensitivity and specificity of FDG PET/CT and enhanced CT of the same periods.
Results: The sensitivity, specificity and accuracy of PET/CT in diagnosis of local recurrence was 92%, 91.89% and 94.44% respectively. The sensitivity, specificity and accuracy of contract enhanced CT in diagnosis of local recur-rence was 72%, 89.19% and 82.5% respectively. The sensi-tivity, specificity and accuracy of PET/CT in diagnosis of distant metastasis was 91.12%, 81.08% and 88.64% respec-tively. The sensitivity, specificity and accuracy of contrast enhansed CT in diagnosis of local recurrence was 72.55%, 86.49% and 78.41% respectively.
Conclusion: In patients with suspected CRCR, FDG-PET/CT appears to be a significantly more accurate method than CT alone for detection of local recurrence and distant metastasis, FDG-PET/CT is sufficiently accurate to become a routine follow-up of patients after colorectal resection.