Correlation of (18)F-FDG/PET SUV(max), SUV(mean), MTV, and TLG with HIF-1α in Patients with Colorectal Cancer

OBJECTIVES: Post-hypoxia hypoxia-inducible factor (HIF)-1α activation plays a vital role in colorectal cancer (CRC) angiogenesis. Although glucose metabolism is induced in some cancer types via HIF-1α, the prognostic significance of HIF-1α in CRC and its correlation with (18)fluorinefluorodeoxyglucose ((18)F-FDG) uptake in positron emission tomography (PET) remain controversial. This study aims to investigate the association between (18)F-FDG/PET parameters and HIF-1α expression in CRC. METHODS: Thirty-six histopathologically confirmed patients with CRC who had (18)F-FDG/PET scans before surgery were enrolled in the study. The correlations between the maximum standardized uptake value (SUV(max)), SUV(mean), metabolic tumor volume (MTV), total lesion glycolysis, HIF-1α overexpression, and histopathological features were evaluated. RESULTS: The tumor location, tumor diameter, perineural invasion, lymphovascular invasion, T and N stage were not significantly correlated with HIF-1α overexpression. In contrast, the tumor differentiation was negatively correlated with HIF-1α expression (r=-0.332, p=0.048). None of the (18)F-FDG/PET parameters was significantly correlated with HIF-1α overexpression. A significant relationship was found between tumor differentiation, tumor necrosis percentage, and MTV (p=0.030, p=0.020). CONCLUSION: The expected association between HIF-1α overexpression and (18)F-FDG/PET parameters was not found in this study. However, there was a relationship between MTV, tumor differentiation, and tumor necrosis percentage. Hence, further studies are required to predict the pathological and prognostic courses of CRC using a diagnostic (18)F-FDG/PET evaluation.