Controversies in the management of colorectal liver metastases: role of PET and PET/CT.

Positron emission tomography (PET) using [F-18]-2-deoxy-2-fluoro-D-glucose (FDG) has emerged as a promising diagnostic modality in recurrent colorectal cancer. Data in the literature show that the addition of FDG-PET changes patient management in up to 30% of patients with potentially resectable liver metastases, mainly by detecting previously unknown extrahepatic disease. Furthermore, FDG-PET is useful in the follow-up of patients who underwent surgical procedures of the liver, since it is sensitive in detecting residual or relapse malignancy in scarred liver tissue following both resection and local ablative techniques. For follow-up during systemic therapy, early FDG-PET appears predictive for response to therapy. FDG-PET, computerized tomography and magnetic resonance imaging are complementary techniques in staging and restaging patients with advanced colorectal cancer. A combination of FDG-PET and CT scanning characteristics seems promising, and integrated PET/ CT is becoming more widely available, although the exact clinical value and efficacy is not yet fully established. In addition, assessment of these modalities in joint reading sessions with radiologist, nuclear medicine physician, medical and surgical oncologists significantly impacts upon patient management. This review evaluates the potential of FDG-PET and combined PET/CT in patients with colorectal liver metastases and discusses potential future possibilities.