The value of MRI scoring method in the differential diagnosis of benign parotid tumors

WU Yipai; HUANG Yanfang; SHU Yanyan; HAN Zhijiang

Abstract：Objective To explore the value of MRI scoring in the differential diagnosis of benign parotid tumors.Methods The MRI images of 145 benign parotid tumors in 137 cases were retrospectively analyzed.There were 58 pleomorphic adenoma(PA)in 58 cases,62 Warthin's tumor(WT)in 54 cases and 25 basal cell adenomas(BCA)in 25 cases.The tumor was located in the caudal lobe,with regular morphology,equal low signal on T2WI,high signal on T1WI,and fast in/out enhancement mode assigned a score of zero.The tumor was located in the no ncaudal lobe,irregular morphology,high signal on T2WI,equal low signal on T1WI,and progressive enhancement modes were assigned 2 points.The value of MRI scores in distinguishing PA,WT,and BCA was evaluated using the receiver operating characteristic curve.Results The MRI scores of WT and PA were 2(0,2)points and 8(6,10)points(Z=10.0348,P＜0.05),respectively.The area under curve(AUC),optimal threshold,sensi-tivity,and specificity for distinguishing the two were 0.980,5 points,93.5%,and 86.6%,respectively;The MRI scores of WT and BCA were 2(0,2)and 4(4,6)points(Z=-3.922,P<0.05),respectively.The AUC,optimal threshold,sensitivity,and specificity for distinguishing the two were 0.866,3 points,79.0%,and 84.0%,respectively;The MRI scores of PA and BCA were 8(6,10)and 4(4,6)points(Z=3.778,P<0.05),respectively.The AUC,optimal threshold,sensitivity,and specificity for distinguishing the two were 0.866,7 points,80.0%,and 74.1%,respectively.Conclusion The MRI score is of great value in the differential diagnosis of benign parotid tumors.WT score is the lowest,PA score is the highest,and BCA is in between.