Abstract
ABSTRACT The malignant adenomyoepithelioma is a rare mammary tumor in women and uncommon in cats with only one report in this species. In this case report, the histopathological and immunohistochemical characteristics of six cases of malignant adenomyopithelioma in the feline mammary gland are described. Microscopic evaluation of tumors showed dense cellular neoplastic proliferation, composed of malignant myoepithelial and epithelial cells, formed by varied arrangements and presenting papillary, tubular and solid nest proliferation. Immunohistochemistry was performed for markers Ki67, Cox-2, RE, RP, p63 and HER-2. All cases were positive for p63, confirming the myoepithelial nature of neoplastic cells. The diagnosis of malignant adenomyopithelioma was made possible through the association between histopathological characteristics and immunohistochemical results.
Highlights
Feline mammary tumors present the third highest incidence among feline tumors, being only behind skin and hematopoietic (Misdorp, 2002; Overley et al, 2005; Cassali et al, 2020)
The malignant adenomyoepithelioma is poorly described in cats, with only one case report in the literature (Campos et al, 2015)
The immunohistochemical results obtained in the analyzed cases are similar to those reported in the first description of malignant adenomyoepithelioma in cats, except that, in the previous report, the immunostaining for Ki67 was 3% and the HER-2 marker showed positivity (Campos et al, 2015)
Summary
Feline mammary tumors present the third highest incidence among feline tumors, being only behind skin and hematopoietic (Misdorp, 2002; Overley et al, 2005; Cassali et al, 2020). The adenomyoepithelioma is a mammary tumor characterized histologically by the proliferation of epithelial and myoepithelial cells. Most of these tumors are benign, but malignant transformation, uncommon, may occur in one or both cellular components (Howlett et al, 2003; Rosen, 2009). A more detailed description of the histopathological and immunohistochemical presentation of malignant adenomyoepitheliomas in felines can help in a more accurate diagnosis of animal mammary neoplasms, clarifying the definition of treatment for the disease. The histopathological evaluation of tumors showed densely cellular neoplastic proliferation, composed of myoepithelial and epithelial cells, formed by varied arrangements, and presenting papillary, tubular, and solid nest proliferation. Clinical information from one case showed that the patient remains alive 330 days after the diagnosis with no signs of metastasis or recurrences
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
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 call
