Features of adenomyoepithelioma of breast:a clinicopathological analysis and review of literature

QI Wenjuan; XU Junqing

doi:10.3969/j.issn.1007-8096.2025.10.006

Abstract：Objective To investigate the clinicopathological features,diagnosis,differential diagnosis,treatment,and prognosis of adenomyoepithelioma(AME).Methods The clinical manifestations,pathological features,immunohistochemical phenotypes,and treatment regimens of 4 patients with breast AME were retrospectively analyzed,and relevant literature was reviewed.Results All the 4 cases were female,with a mean age of 52 years(range:32-81 years).Microscopically,the tumors showed proliferation of glandular epithelium and myoepithelium.The glandular epithelium was located on the inner side of the glandular lumens,appearing as cuboidal or low columnar cells with eosinophilic cytoplasm,and secretions were visible.The myoepithelium was situated on the outer side of the glandular lumens,presenting as fusiform,polygonal,or clear cells.No cellular atypia or mitotic activity was observed in these cells.Immunohistochemically,the glandular epithelium was positive for CK7;the myoepithelium was positive for Calponin,CK5/6,p63,and SMA;the Ki-67 proliferation index was lower than 10%;HER2 expression was 0 in all cases;ER,PR,CEA,and S-100 were expressed to varying degrees,with positive rates of<5%.Conclusion Breast adenomyoepithelioma is a rare benign tumor.It is easily misdiagnosed as breast cancer in clinical practice due to its complex features and morphology variability.The diagnosis depends on the combination of morphological observations and immunohistochemical results.Local surgical resection is the main treatment modality,and the prognosis is favorable.