Application Study Of Multi-slice CT In Distinguishing Between Benign Parotid Tumors And Malignant Parotid Tumors

Background and purpose:Parotid gland is rich in fat and has obvious contrast with bone and muscle in CT image. The preoperative examination of CT could help to evaluate the scale of tumor invasion and the relationship between tumor and normal tissues so that the proper therapy could be properly designed. The purpose of this study was to explore the clinical value of multi-slice CT in distinguishing between benign parotid tumors and malignant parotid tumors and to improve the diagnostic accuracy.Methods:CT scanning images of72parotid tumor patients were analyzed. The location, shape, density, edge, cystic necrosis and degree of enhancement of the tumors were analyzed, degree of cervical lymph node swelling were analyzed, and all the analysis results were compared to pathological results.Results:80lesions were diagnosed in tumors, among which59(73.8%)lesions were benign tumors and21(26.2%) lesions were malignant tumors. The CT images of benign tumors showed that42(71.2%) of them were located in the superficial lobe and with regular shape and uniform density,62.7%of them had clear edge,57.6%of them showed mild or moderate enhancement.2cases of benign tumors presented cervical lymph node swelling, which were proved to be pathological inflammatory mass after operation. Whereas in the CT images of malignant tumors12(57.1%) of them were located in the deep lobe or in both of the superficial lobe and the deep lobe.15(71.4%) of them had irregular shape and uneven density.81%of them had unclear edge.71.4%of malignant tumors were significantly enhanced.9cases of malignant tumor were with cervical lymph node metastasis.4cases of malignant tumor were with the damage symptoms of nerve and vein. There was statistical difference between the shape, edge, density, cystic necrosis and cervical lymph node metastasis of the two groups of tumors(P<0.05), while the location and the degree of enhancement of the two groups of tumors showed no statistical difference(P>0.05).Conclusion:Most of benign and malignant parotid tumors can be correctly diagnosed by analyzing multi-slice CT images. Parotid tumor had clear edge,with regular shape and uniform density, showed mild or moderate enhancement, is more likely to be a benign tumor. Otherwise,it might be a malignant tumor. Increscent lymph node and the invasion of nerve and vein by tumor are the diagnostic features of malignant parotid tumor.