Multiparametric evaluation by simultaneous PET-MRI examination in patients with histologically proven laryngeal cancer

Abstract

Objectives: To evaluate the relationship between metabolic 18Fluoro-Deoxyglucose-Positron Emission Tomography (18FDG/PET) and morpho-functional parameters derived by Magnetic Resonance Imaging (MRI) in patients with histologically proven laryngeal cancer. To assess the clinical impact of PET/MRI examination on patient's staging and treatment planning.

Methods: 16 patients with histologically proven laryngeal cancer were enrolled and underwent whole body PET/CT followed by a dedicated PET/MRI of the head/neck region. Data were separately evaluated by two blinded groups: metabolic (SUV and MTV), diffusion (ADC) and perfusion (K_trans, V_e, k_ep and iAUC) maps were obtained by positioning regions of interest (ROIs). Tumoral local extension assessed on PET/MRI was compared to endoscopic findings.

Results: A good inter-observer agreement was found in anatomical location and local extension of PET/MRI lesions (Cohen's kappa 0.9). PET/CT SUV measures highly correlate with ones derived by PET/MRI (e.g., p=0.96 for measures on VOI). Significant correlations among metabolic, diffusion and perfusion parameters have been detected. PET/MRI had a relevant clinical impact, confirming endoscopic findings (6 cases), helping treatment planning (9 cases), and modifying endoscopic primary staging (1 case).

Conclusions: PET/MRI is useful for primary staging of laryngeal cancer, allowing simultaneous collection of metabolic and functional data and conditioning the therapeutic strategies.

Keywords: Laryngeal cancer; Magnetic resonance imaging; PET/MRI; Positron emission tomography.