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 (18)F-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 (18)F-FDG-PET/MRI including DWI and T1w-DCE. SUV(max), SUV(mean), ADC(mean), ADC(min) and K (trans), k (ep) and v (e) were measured for each tumour and correlated using Spearman’s ρ. RESULTS: Significant correlations were observed between SUV(mean) and K (trans) (ρ = 0.43; p ≤ 0.05); SUV(mean) and k (ep) (ρ = 0.44; p ≤ 0.05); K (trans) and k (ep) (ρ = 0.53; p ≤ 0.05); and between k (ep) and v (e) (ρ = -0.74; p ≤ 0.01). There was a trend towards statistical significance when correlating SUV(max) and ADC(min) (ρ = -0.35; p = 0.08); SUV(max) and K (trans) (ρ = 0.37; p = 0.07); SUV(max) and k (ep) (ρ = 0.39; p = 0.06); and ADC(mean) and v (e) (ρ = 0.4; p = 0.06). CONCLUSION: Simultaneous (18)F-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.