Abstract
Naturally occurring mammary tumours are uncommon in prosimians. A 20-year-old female ring-tailed lemur (Lemur catta) developed bilateral enlargement of the mammary glands. Surgical removal revealed that both masses were comprised of multiple nodules and cystic areas that entirely replaced the normal glands. Histologically, a benign neoplastic biphasic cellular proliferation, composed of luminal-epithelial and basal-myoepithelial components, was identified. Immunohistochemical analysis for expression of cytokeratin (CK) AE1/AE3, CK7, CK5+8, CK14, vimentin, p63 and 14-3-3σ highlighted the biphasic nature of the neoplasm. A low mitotic count, low Ki67 labelling index, expression of oestrogen receptor-α, lack of expression of human epidermal growth factor receptor and a 3-year disease-free period without recurrence supported the benign nature of the tumour. Macroscopically, histologically and immunohistochemically this neoplasm resembled benign adenomyoepithelioma of the breast in women. This is the first complete report of a naturally occurring mammary tumour in a ring-tailed lemur.
Highlights
The first population were cuboidal to columnar luminal epithelial cells, with poorly-demarcated borders, moderate amounts of eosinophilic cytoplasm, an oval nucleus, in a central to basal position, and finely stippled chromatin with a single basophilic nucleolus
Similar features were present in this case, in which neoplastic nodules effaced the mammary gland and compressed a regional lymph node
The immunohistochemical profile described for human AME includes positivity of the luminal epithelium for pan-CK, CK7, CK8 and for CK5, CK14, vimentin, 14-3-3σ and p63 in the myoepithelium
Summary
The first population were cuboidal to columnar luminal epithelial cells, with poorly-demarcated borders, moderate amounts of eosinophilic cytoplasm, an oval nucleus, in a central to basal position, and finely stippled chromatin with a single basophilic nucleolus. The histological and immunohistochemical findings of the tumour in the present case fulfilled the diagnostic criteria for AME of the breast in women.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
