Discriminating between benign and malignant salivary gland tumors using diffusion-weighted imaging and intravoxel incoherent motion at 3 Tesla - 01/02/23
Highlights |
• | Diffusion-weighted MRI is of value for the diagnosis of pleomorphic adenoma, which is the most common type of salivary gland tumor. |
• | Intravoxel incoherent motion has better accuracy than diffusion-weighted MRI for discriminating between benign from malignant salivary gland tumors. |
• | High ADCmean or Dmean values and high D*mean values show best performances for pleomorphic adenoma and Warthin's tumor characterization, respectively. |
• | Clinically useful parameter thresholds can be obtained by maximizing specificity for pleomorphic adenoma and Warthin's tumor. |
Abstract |
Purpose |
The purpose of this study was to retrospectively evaluate the diagnostic performances of diffusion-weighted imaging (DWI) and intravoxel incoherent motion (IVIM) for discriminating between benign and malignant salivary gland tumors (SGTs).
Materials and methods |
Sixty-seven patients with 71 SGTs who underwent MRI examination at 3 Tesla were included. There were 34 men and 37 women with a mean age of 57 ± 17 (SD) years (age range: 20–90 years). SGTs included 21 malignant tumors (MTs) and 50 benign SGTs (33 pleomorphic adenomas [PAs] and 17 Warthin's tumors [WTs]). For each SGT, DWI and IVIM parameters, mean, skewness, and kurtosis of apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*) and perfusion volume fraction (f) were calculated and further compared between SGTs using univariable analysis. Areas under the curves (AUC) of receiver operating characteristic of significant parameters were compared using the Delong test.
Results |
Significant differences in ADCmean, Dmean and D*mean were found between SGTs (P < 0.001). The highest AUC values were obtained for ADCmean (0.949) for identifying PAs and D*mean (0.985) for identifying WTs and skewness and kurtosis did not outperform mean. To discriminate benign from malignant SGTs with thresholds set to maximize Youden index, IVIM and DWI produced accuracies of 85.9% (61/71; 95% CI: 75.6–93.0) and 77.5% (55/71; 95% CI: 66.0–86.5) but misdiagnosed MTs as benign in 28.6% (6/21) and 61.9% (13/21) of SGTs, respectively. After maximizing specificity to 100% for benign SGTs, the accuracies of IVIM and DWI decreased to 76.1% (54/71; 95% CI: 64.5–85.4) and 64.8% (46/71; 95% CI: 52.5–75.8) but no MTs were misdiagnosed as benign. IVIM and DWI correctly diagnosed 66.0% (33/50) and 50.0% (25/50) of benign SGTs and 46.5% (33/71) and 35.2% (25/71) of all SGTs, respectively.
Conclusion |
IVIM is more accurate than DWI for discriminating between benign and malignant SGTs because of its advantage in detecting WTs. Thresholds set by maximizing specificity for benign SGTs may be advantageous in a clinical setting.
Le texte complet de cet article est disponible en PDF.Keywords : Diffusion-weighted magnetic resonance imaging, Histogram analysis, Head and neck, Intravoxel incoherent motion, Salivary gland neoplasms
Abbreviations : ADC, AUC, CT, CI, D, D*, DWI, f, FP, FN, ICC, IVIM, IQR, MRI, MT, PA, SGT, SD, TP, TN, WT
Plan
Vol 104 - N° 2
P. 67-75 - février 2023 Retour au numéroBienvenue sur EM-consulte, la référence des professionnels de santé.