The Study Of Imaging Features Of The Breast Phyllodes Tumor And Correlations Between The Imaging Features And Pathologic Grade

Purpose:To characterize the Mammography?Ultrasound and MRI features of breast phyllodes tumor,the correlation between imaging findings and pathologic grade was further studied,In order to improve the preoperative diagnostic accuracy and provide reliable imaging information for appropriate operation selection and prognosis of this disease.Methods:The subjects of this study were patients who were admitted to the Tianjin tumor hospital and confirmed by pathology as phyllodes tumor of the breast.Data of 69 cases of phyllodes tumor had preoperative Mammography and 121 cases had preoperative Ultrasound from May,2013 to December,2016 were collected,and data of 40 cases of phyllodes tumor had preoperative MRI from December,2006 to April,2017 were collected.All of the images were analyzed according to the lexicon of BI-RADS designed by ACR in 2013.Mammography findings including tumor morphology,margin,density and"lucent halo"of the lesions were analyzed.Ultrasound findings including tumor morphology,border,internal echo,posterior echo,CDFI and elastic characteristics of the lesions were analyzed.MRI findings including morphology,plain MRI,dynamic contrast-enhanced MRI and ADC value were analyzed.These imaging features were compared in different pathologic grade by Fisher exact test;The ADC value and pathologic grade were statistically analyzed by Kruskall-Wallis.P<0.05 were considered statistically significant.Results:Sixty-nine patients had preoperative mammography,including 25 benign,17borderline and 27 malignant.On mammography,phyllodes tumors always represent a high density lobular mass with circumscribed margins;some masses represent"lucent halo",the tumor"lucent halo"accounted for 18?72%?,6?35.3%?and 9?33.3%?respectively,the difference was statistically significant?P=0.011?.One hundred and twenty-one patients had preoperative ultrasound,including 43benign,36 borderline and 42 malignant.The irregular shape on ultrasound were accounting for 7?16.3%?,26?72.2%?,and 33?78.6%?respectively.They always showed hypoechoic mass and enhanced posterior acoustic.The not-circumscribed margin of the tumor were accounting for 2?4.7%?,13?36.1%?and 28?66.7%?respectively.The heterogeneous internal echo were accounting for 30?69.8%?,31?86.1%?and 41?97.6%?respectively.The irregular echo free zone were accounting for 1?2.3%?,8?22.2%?and 26?62.0%?respectively.All of the above features are significant between benign,borderline and malignant phyllodes tumor?P<0.05?,the borderline or malignant phyllodes tumor was suggested.Forty patients?41 lesions?had preoperative MRI,including 22 benign,11borderline and 8 malignant.They always showed a mass on MRI.The hyper-intense signal on T₁WI were accounting for 1?4.5%?,2?18.2%?and 4?50%?respectively.The heterogeneous signal on T₂WI were accounting for 7?31.8%?,6?54.5%?and7?87.5%?respectively.The heterogeneous enhancement were accounting for 3?13.6%?,6?54.5%?and 8?100%?respectively.The irregular non-enhancement region were accounting for 1?4.5%?,2?18.2%?and 7?87.5%?respectively.The time-signal intensity curve showed type?or type?were accounting for 9?40.9%?,11?100%?and 7?87.5%?respectively.All of the above features are significant between benign,borderline and malignant phyllodes tumor?P<0.05?.Most of phyllodes tumor represent lobular shape with circumscribed margin on MRI,the ADC value was slow;however,the shape,margin and ADC value is not helpful in distinguishing benign from malignant phyllodes tumor.Conclusion:All phyllodes tumor presented as a mass with lobular shape on imaging and most of them usually showed high density.The"lucent halo"on mammography correlated with more likelihood of benign phyllodes tumor;The internal heterogeneous echo/heterogeneous signal,heterogeneous enhancement and the time-signal intensity curve showed type?or type?suggest borderline or malignant phyllodes tumor.Preoperative imaging,especially MRI and ultrasound may provide some information for preoperative diagnosis of breast phyllodes tumors and the pathologic grade can be suggested.