Preliminary study on biexponential diffusion-weighted imaging (dwi) for the prediction of differentiation degree of nasopharyngeal carcinoma

We discussed the value of biexponential diffusion-weighted imaging (DWI) in predicting the differentiation degree of nasopharyngeal carcinoma (NPC). Biexponential DWI was applied to 33 cases of nonkeratinizing NPC, which were classified into differentiated group (14 cases) and undifferentiated group (19 cases). The two groups were compared with respect to DWI parameters (ADCstand, ADCslow, ADCfast, Ffast). ADCstand, ADCslow, ADCfast and Ffast values of differentiated group were 0.920±0.131×10-3 mm2/s, 0.680±0.115×10-3 mm2/s, 22.3±13.9 mm2/s and 0.316±0.078, respectively; the corresponding values of undifferentiated group were 0.952±0.203×10-3 mm2/s, 0.672±0.116×10-3 mm2/s, 17.8±20.3 mm2/s and 0.299±0.120, respectively; ADCfast was significantly different between the two groups (P<0.05). The sensitivity and specificity of ADCfast in predicting the differentiation degree of NPC was 85.7% and 63.2%, respectively. ADCfast has a certain value in predicting the differentiation degree of primary NPC.