Correlation between tumor glucose metabolism and multiparametric functional MRI (IVIM and R2*) metrics in cervical carcinoma: Evidence from integrated 18 F-FDG PET/MR.

Abstract

Multiparameter, multimodality 18 F-FDG PET/MRI holds great potential for the diagnosis of cervical cancer based on the correlation between tumor glucose metabolism and imaging parameters. To characterize the heterogeneity of tumor glucose metabolism by evaluating the correlation between 18 F-FDG uptake parameters and multiparametric functional MRI metrics in cervical carcinoma. Retrospective. Fifty-four patients with cervical carcinoma. Hybrid PET/MR (3T), multi-b DWI, and R2* mapping. The maximum and mean standardized uptake values (SUVmax and SUVmean , respectively) from PET and functional MRI metrics (D, D*, f, and R2*) were obtained. Cervical carcinoma tissues also underwent HIF-1α, VEGF, and GLUT-1 immunohistochemical staining. Single-factor Spearman rank and Pearson correlation analysis and multiple linear regression (MLR) analysis were applied. R2*, D, and f have different degrees of correlation (moderate, weak, moderately strong correlation, respectively) with SUVmax and SUVmean (r = 0.530 and 0.527, and P < 0.001 for R2*; r = -0.292 and -0.291, and P < 0.05 for D; r = 0.539 and 0.520, and P < 0.001 for f, respectively). Immunohistochemical staining showed that HIF-1α expression has a moderate degree of correlation with R2* (r = 0.491; P < 0.001); GLUT-1 expression was significantly correlated with SUVmax and SUVmean (r = 0.633 and 0.622; P < 0.001), and VEGF expression had a moderately strong correlation with f (r = 0.457; P = 0.001). If SUVmax is the dependent variable, MLR yields an R-squared value after adjustment (adjusted R-squared) = 0.358, and F = 10.833 (P < 0.001), and the fitting linear equation is Y (SUVmax ) = 9.184 + 0.161X1 (R2*)+50.343X2 (f)-4.780 (D). Otherwise, MLR yields the adjusted R-squared = 0.342, and F = 10.187 (P < 0.001), and the linear regression equation is Y (SUVmean ) = 5.925 + 0.102X1 (R2*)+28.029X2 (f)-2.907X3 (D). The functional MRI sequence parameters R2*, f, and D can provide information on the hypoxic condition, blood perfusion, and molecular diffusion of the tumor. 18 F-FDG PET/MR multi-imaging technique can be adopted to evaluate the heterogeneity of glucose metabolism in cervical carcinoma. 3 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:1704-1712.