Differential diagnostic value of diffusion-weighted and dynamic contrast-enhanced MR imaging in non-cystic lesions in floor of the mouth.

METHODS:: A total of 82 patients were included in this study. The apparent diffusion coefficient (ADC) values and time-signal intensity curves (TICs) were measured. Clinical characteristics, ADC value, and TIC pattern were compared between benign and malignant FOM lesions. Receiver operating characteristic curve and logistic regression analyses were performed to evaluate respective and combined value of ADC value and TIC pattern for differential diagnosis. The retrospective study was approved by our institutional review board, and the need for informed consent was waived.

RESULTS:: The area under the curve ADC value and TIC pattern were 0.71 and 0.73, respectively. The combined use of ADC value and TIC pattern increased the area under the curve value to 0.81 [95% confidence interval (CI), (0.66-0.97)]. ADC < 1.23 × 10-3 mm2 s-1 (odds ratio, 45.8; 95% CI, 2.8-737.9) and both the plateau and washout TIC patterns (OR, 6.8; 95% CI, 1.8-24.8) were significantly associated with malignancy of FOM lesions.

CONCLUSIONS:: Our results suggest that both diffusion-weighted imaging and DCE-MRI could contribute to the differential diagnosis of non-cystic FOM lesions, especially when used in combination.