Prognostic significance of 18FDG PET/CT in colorectal cancer patients with liver metastases: A meta-analysis

Abstract

Background: The role of 18-fluorodeoxyglucose positron emission tomography CT (18FDG PET/CT), as a prognostic factor for survival in colorectal cancer patients with liver metastases, is still controversial. We sought to perform a meta-analysis of the literature to address this issue. Methods: A systematic literature search was performed to identify the studies that associated 18FDG PET/CT to clinical survival outcomes of patients with liver metastases. Methodological qualities of the included studies were also assessed. The summarized hazard ratio (HR) was estimated by using fixed- or random-effect model according to heterogeneity between trails. Results: By analyzing a total of 867 patients from 15 studies, we found that PET/CT for metabolic response to the therapy was capable of predicting event-free survival (EFS) and overall survival (OS) with statistical significance, and the HR was 0.45 (95 % confidence interval [CI], 0.26-0.78) and 0.36 (95 % CI, 0.18-0.71), respectively. Furthermore, pre-treatment 18FDG PET/CT with high standardized uptake value (SUV) was also significantly associated with poorer OS HR, 1.24; (95 % CI, 1.06-1.45). However, we did not find a statistically significant effect of post-treatment SUV for predicting OS HR, 1.68; (95 % CI, 0.63-4.52). Conclusions: The present meta-analysis confirms that 18FDG PET/CT is a useful tool to help predict survival outcomes in patients with liver metastases.