Pleomorphic lobular carcinoma of the canine mammary gland: histopathologic and immunohistochemical features

Abstract

This report describes the morphological and immunohistochemical findings of a case of mammary gland pleomorphic lobular carcinoma occurring in the canine species. Histologically, it was characterized by the presence of tumor cells loosely dispersed in the stroma or arranged in a linear pattern showing relatively abundant eosinophilic cytoplasm with an eccentric nuclei. These morphological features, characteristic of pleomorphic mammary gland lobular carcinoma in woman, were not previously described in dogs.

Comparative epidemiological study of breast cancer in humans and canine mammary tumors: insights from Portugal

“…Another aspect that needs to be noteworthy is that the morphological types of infiltrating duct and lobular carcinoma are not documented in VET-ICD-O-canine-1, preventing their comparison with human counterparts. Although pleomorphic lobular carcinomas were previously described in canine mammary tumors ( 72 – 74 ), they were not included in the first edition of VET-ICD-O-canine-1, highlighting the need for their inclusion in a future update of this classification system.…”

Clinicopathological and immunohistochemical features of pleomorphic lobular mammary carcinoma in a female dog

“…It is characterised as an aggressive tumour with poor prognosis, with the first case described within a female dog published in 2002 (4). The study compared the cytomorphological and immunohistochemical findings of mammary neoplasm in female dogs and women, showing similarities between species (1,2,4).…”

“…Pleomorphic lobular carcinoma (PLC) is an uncommon and special type of malignant mammary neoplasia that corresponds to a variant of invasive lobular carcinomas (ILC) in women (3). It is characterised as an aggressive tumour with poor prognosis, with the first case described within a female dog published in 2002 (4). The study compared the cytomorphological and immunohistochemical findings of mammary neoplasm in female dogs and women, showing similarities between species (1,2,4).…”

“…PLCs are known to be immunohistochemically positive for hormone receptors, in addition to having a high proliferation rate represented by the Ki-67 positive cells percentage, and positive expression of human epidermal growth factor receptor 2 (HER-2) (2,5). The absence of E-cadherin (E-cad) and β-catenin membranous staining is characteristic of PLC for women and female dogs, and it has been suggested that loss of these markers 34 can help the diagnose PLC in both species (2)(3)(4)(5)(6). Strong immunostaining of cytoplasmic cells to cytokeratins can define the epithelial origin of PLC (2,7).…”

Avaliação da superexpressão da proteína p53 e das mutações no éxon 8 do gene TP53 em carcinomas mamários caninos e glândulas normais

“…O uso da técni-ca de imuno-histoquímica em Patologia Veterinária tem sido limitado devido à falta de anticorpos para os tecidos animais, no entanto podem ser utilizados os anticorpos que apresentam reatividade cruzada entre antígenos humanos e animais (Keller et al 2007) e, juntamente com outros exames (citologia e histologia), contribuem para o diagnóstico definitivo e preciso desses tumores (Cassali et al 2002). Análises imuno-histoquímicas para descoberta de receptores de estrógeno, progesterona, fator de crescimento epidermal, oncogenes, supressores de tumor como o gene p53 (Tp53) entre outros, são de grande valor para fornecer um prognóstico mais acurado para cães com neoplasmas mamários (Hellmén 2005).…”