Study Of The Relationship Between Mammaglobin、ETV6-NTRK3 Fusion Genes And Mammary Analogue Secretory Carcinoma

[Background]MASC(mammary analogue secretory carcinoma of salivary glands,MASC)is a rare malignant tumor,it occurs in the salivary gland with morphological and genetic features of secretory carcinoma of the breast,which was first reported by Skalova and has not yet been separated division from salivary gland tumors by WHO.MASC was invasive,the local recurrence rate was 15%,the lymph node metastasis rate was up to 20%,and the local metastasis rate was up to 5%.However,the morphology and histological structure of the tumor are very similar to those of acinar cell carcinoma and some other malignancies.At present,there is no definite criteria for pathological diagnosis,and the diagnosis often requires genetic examination.The tumor has a characteristic translocation of the ETV6-TRK3 gene,but not all MASC have gene translocation.Therefore,the correct diagnosis of MASC is difficult,and there are no effective measures to prevent local recurrence and metastasis after operation.Therefore,the study of the target genes of MASC diagnosis、recurrence and metastasis is of great significance.[Methods]Select 26 group were diagnosed as AciCC(acinic cell carcinoma)salivary gland specimens,according to the classification of head and neck cancer by WHO in 2005 year and literature review,we selected 14 cases of MSAC;Observing the clinical samples of mammaglobin,S-100,P63,Ki-67 expression by immunohistochemical SP method;To detection of ETV6 gene breaking cases of tumor cells were observed by ETV6 dual color break apart probe FISH assay which cases’ mammaglobin were positive expression;The link between tumor cells in tumor specimens was observed under transmission electron microscope.[Results]①The chosen fourteen cases of mammary analogue secretory carcinoma of salivary gland showed positive expression of mammaglobin,S-100 and Ki-67,and negative expression of P63.②Eight of fourteen mammary analogue secretory carcinomas of salivary gland with positive expression of mammaglobin also tested positive for the ETV6-NTRK3 translocation.③Transmission electron microscopy revealed a decrease in microvilli and abnormal cell junctions in the tumor specimens.[conclusion]Mammaglobin and ETV6-NTRK3 fusion gene detection could help to distinguish mammary analogue secretory carcinoma of salivary gland.And apical junctional complexes were observed in the loosely connected tumor cells,which might be closely related with the development and malignant transformation of MASC.