Detecting Bone Invasion of the Maxilla by Oral Squamous Cell Carcinoma: Diagnostic Accuracy of Preoperative Computed Tomography Versus Magnetic Resonance Imaging

Purpose: For planning of the surgical resection, computed tomography (CT) and magnetic resonance imaging (MRI) are commonly used for the preoperative assessment of bone invasion of the maxilla. The purpose of this study was to compare the diagnostic test accuracy of CT and MRI for detecting bone invasion of the maxilla in patients with squamous cell carcinoma of the maxilla (MSCC). Materials and Methods: We conducted a retrospective cross-sectional study and enrolled a consecutive number of patients with primary MSCC between 2000 and 2017 who underwent either preoperative CT or MRI scans. The outcome variable was the absence or presence of bone invasion, with histopathologic examination of the resection specimen as the gold standard. The predictor variable was the imaging technique (CT and MRI). The imaging results on bone invasion were compared with the histopathologic results. Sensitivity and specificity were calculated, and the 2-sided Fisher exact test was used to calculate statistically significant differences between the unpaired CT and MRI results. Receiver operating characteristic curves were computed, and the area under the curve (AUC) was calculated. Results: The study included 72 patients (29 male and 43 female patients) with a mean age of 72 years. A total of 41 CT scans and 31 MRI scans were available. Histopathologic examination showed bone invasion in 45 cases: 26 of 41 patients with CT scans (63%) and 19 of 31 patients with MRI scans (61%). CT yielded 2 false-positive and 2 false-negative results, with a sensitivity of 92%, specificity of 87%, and AUC of 0.895. MRI yielded 5 false-positive and 2 false-negative results, with a sensitivity of 89%, specificity of 58%, and AUC of 0.739. No significant differences were observed for sensitivity (P >.999) and specificity (P =.185). Conclusions: In the absence of metallic dental restorations, CT could detect bone invasion more accurately than MRI in this study; however, the difference was not statistically significant. The imaging method of choice may depend on other situational factors.