Whole-tumor histogram analysis of synthetic MRI for discriminating benign from malignant sinonasal tumors: correlations with histopathologic factors.

Background: Histogram parameters from synthetic magnetic resonance imaging (SyMRI) may provide more diagnostic information than mean values in differentiating benign from malignant sinonasal tumors. The histopathologic basis of SyMRI in characterizing malignant sinonasal tumors is still unclear. This study aimed to explore the potential value of SyMRI quantitative maps with whole-lesion histogram analysis in the diagnosis of benign and malignant sinonasal tumors and the correlations between SyMRI-derived histogram metrics and histopathologic features in malignant sinonasal tumors.

Methods: A total of 76 patients (29 benign and 47 malignant) with sinonasal tumors were enrolled. Nine histogram parameters of the whole tumor were extracted from T1, T2, and proton density (PD) quantitative maps, respectively. Univariate and multivariate analyses were utilized to explore the association between benign and malignant sinonasal tumors. Models based on single, combined quantitative maps, and clinical features were established to evaluate the diagnostic performance. The Spearman correlation coefficient was used to assess the correlation between histogram quantitative metrics of SyMRI and histopathological features.

Results: For SyMRI parameters, 18 histogram metrics showed significant differences between benign and malignant sinonasal tumors (all P<0.05). The combined model based on T2 map (T2-90th percentile, Minimum, and Kurtosis) and clinical features (age and bone destruction) attained the best diagnostic performance in discrimination of benign and malignant sinonasal tumors with the highest area under the curve (AUC) of 0.908, sensitivity of 91.5%, and specificity of 82.8%. Moreover, several histogram quantitative parameters of malignancies were correlated with Ki-67 (r=-0.465 to -0.28), p53 (r=-0.476 to 0.414) and epidermal growth factor receptor (EGFR) status (r=-0.428/0.419). The T2-90th Percentile was independently associated with Ki-67 labeling index (LI) (P<0.05).

Conclusions: Whole-tumor histogram quantitative parameters of SyMRI could further improve the diagnostic performance in differentiating benign from malignant sinonasal tumors and may serve as potential biomarkers in assessing the histopathologic features.