In Vivo Correlation of Glucose Metabolism, Cell Density and Microcirculatory Parameters in Patients with Head and Neck Cancer: Initial Results Using Simultaneous PET/MRI

Objective To demonstrate the feasibility of simultaneous acquisition of F-18-FDG-PET, diffusion-weighted imaging (DWI) and T1-weighted dynamic contrast-enhanced MRI (T1w-DCE) in an integrated simultaneous PET/MRI in patients with head and neck squamous cell cancer (HNSCC) and to investigate possible correlations between these parameters. Methods 17 patients that had given informed consent (15 male, 2 female) with biopsy-proven HNSCC underwent simultaneous F-18-FDG-PET/MRI including DWI and T1w-DCE. SUVmax, SUVmean, ADC(mean), ADC(min) and K-trans, k(ep) and v(e) were measured for each tumour and correlated using Spearman's rho. Results Significant correlations were observed between SUVmean and K-trans (rho = 0.43; p <= 0.05); SUVmean and kep (rho = 0.44; p <= 0.05); K-trans and kep (rho = 0.53; p <= 0.05); and between kep and v(e) (rho = -0.74; p <= 0.01). There was a trend towards statistical significance when correlating SUVmax and ADC(min) (rho = -0.35; p = 0.08); SUVmax and K-trans (rho = 0.37; p = 0.07); SUVmax and kep (rho = 0.39; p = 0.06); and ADC(mean) and v(e) (rho = 0.4; p = 0.06). Conclusion Simultaneous F-18-FDG-PET/MRI including DWI and T1w-DCE in patients with HNSCC is feasible and allows depiction of complex interactions between glucose metabolism, microcirculatory parameters and cellular density.