Correlation between 18F-FDG PET/MR parameters with the expression level of epidermal growth factor receptor and the diagnostic value of PET/MR in head and neck squamous cell carcinoma

Objective: To investigate the correlation between parameters of PET/MR and the expression level of epidermal growth factor receptor (EGFR) in head and neck squamous cell carcinoma (HNSCC) and to evaluate diagnostic efficacy of independent and combined PET/MR parameters for the expression level of EGFR. Materials and methods: 21 patients who had undergone PET/MR and been proven HNSCC pathologically were included in this retrospective study. The PET/MR sequences included 18-flurodeoxyglucose (18F-FDG) PET, T1, T2-weighted imaging, DWI, ADC and DCE. Parameters including ADCmean from DWI, Ktrans, Ve, Kep from DCE, and SUVmean, SUVmax from PET were obtained. Immunohistochemical method was used to detect the expression level of EGFR. The associations between parameters of PET/MR and EGFR expression level were analyzed by Spearman's analysis. Logistic regression was utilized to establish the diagnostic model of EGFR expression level with PET/MR parameters. The efficacy of the independent and combined diagnostic model for EGFR expression level in HNSCC was analyzed by ROC curve. P value ≤ 0.05 was considered statistically significant. Results: (1) Expression level of EGFR was correlated to SUVmean with correlation coefficient of 0.47 (p = 0.05). (2) There was significant difference of SUVmean between the EGFR high- and low-expression groups (p = 0.02). (3) Combination of PET/MR improved the diagnostic efficacy for expression level of EGFR, with AUC = 0.93. Conclusion: There were different degrees of correlation between PET/MR parameters and EGFR expression level in HNSCC. Combination of PET/MR might improve diagnostic efficacy of EGFR expression level.