Quantitative Analysis and Pathological Basis of Signal Intensity on T2-Weighted MR Images in Benign and Malignant Parotid Tumors

Abstract

To investigate the value of the signal intensity on T2-weighted magnetic resonance (MR) imaging using quantitative analysis in the differentiation of parotid tumors. Materials and Methods: MR data of 80 pleomorphic adenomas (PAs), 68 Warthin tumors (WTs), and 34 malignant tumors (MTs) confirmed by surgery and histology were retrospectively analyzed. The signal intensities of tumor, normal parotid gland, spinal cord, and buccal subcutaneous fat were measured, and the signal intensity ratios (SIRs) between the tumor and the three references were calculated. Receiver operating characteristic curve was used to determine the optimal threshold and diagnostic efficiency of SIR for differentiating PAs, WTs, and MTs. Results: The area under the curve (AUC) of tumor to parotid gland SIR (SIR P ), tumor to spinal cord SIR (SIR C ), and tumor to buccal subcutaneous fat SIR (SIR F ) for differentiating PAs and WTs was 0.922, 0.918, and 0.934, respectively. The sensitivity and specificity at an optimal SIR threshold were 86.3% and 91.2%, 80.0% and 97.1%, and 85.0% and 94.1%, respectively. The AUC of SIR P , SIR C , and SIR F for distinguishing PAs from MTs was 0.793, 0.802, and 0.774, respectively. The sensitivity and specificity at an optimal SIR threshold was 86.3% and 61.8%, 80.0% and 73.5%, and 82.5% and 73.5%, respectively. The AUC of SIR P , SIR C , and SIR F for distinguishing WTs from MTs was 0.716, 0.709, and 0.759, respectively. The sensitivity and specificity at an optimal SIR threshold were 61.8% and 82.4%, 55.9% and 82.4%, and 64.7% and 86.8%, respectively. Conclusion: SIR P , SIR C , and SIR F on T2-weighted MR images had high diagnostic efficiency for differentiating between PAs and WTs, while SIR P and SIR C for differentiating between PAs and MTs, and SIR F for differentiating between WTs and MTs had relatively high diagnostic efficiency.

Value of T2-weighted-based radiomics model in distinguishing Warthin tumor from pleomorphic adenoma of the parotid

“…In both the training and validation sets, the performance of our clinical model had higher AUCs of 0.923 and 0.926 than the radiomics models, which differs from previous studies [19,21], suggesting clinical models may play a more critical role than radiomics in differentiating WT from PA. In the current study, we found that SI of WT on T2WI in the training set was significantly higher than that of PA, and SI on T1WI was the opposite, which may be related to the abundance of epithelium signals [37]. We also found that some clinical features were more common in WTs than PAs, such as a predisposition in men and smokers, which is consistent with previous reports [21].…”