Canine mammary cancer

Abstract

Canine mammary cancer (CMC) is one of the most common neoplasms in intact females in comparison to other species. Several risk factors have been identified, including breed, genetic predisposition, age, reproductive history, hormonal influence, diet, and body condition, in addition to previous lesions to the mammary gland, such as mammary atypical hyperplasia. An understanding of the genetic markers for the disease and a clinical approach are important for establishing a specific therapy that can allow adequate patient survivorship. Overexpression of the HER-2 gene in canines and humans is associated with a poor clinical prognosis, mainly short survivorship, although the clinical relationship is not clear. The incidence of HER-2 in female dogs can range from 29.7% to 38%. However, overexpression of HER-2 is not necessarily associated with malignancy processes of the mammary tissue, although it participates in cellular proliferation. Finally, canines remain one of the most important models for comparative oncology with humans due to the great similarity in the spontaneous presentation and development of cancer, and in the high homology in the amino acid sequence.

The Novel Diagnostic Techniques and Biomarkers of Canine Mammary Tumors

“…Human epidermal growth factor receptor 2 (HER-2, also known as HER-2 neu or ErbB-2) is also a noteworthy tumor marker [ 62 , 63 , 64 , 65 , 66 , 67 ]. It is a protooncogene that encodes a glycoprotein responsible for the stimulation of cell proliferation and differentiation.…”

“…In women, HER-2 overexpression is strongly connected with high tumor aggressiveness, lack of response to cytotoxic and endocrine therapies, and in general decreased survival [ 62 ]. However, if HER-2 is overexpressed at the early stages of the disease, it can be used as a perfect therapeutic target.…”

“…However, not all the studies agree with that statement [ 64 ]. It is suggested that HER-2 plays a role in tumor proliferation in canines, but not necessarily in malignant transformation [ 62 ]. Various studies confirmed the correlation between HER-2 expression and tumor mitotic index, high histological grade, and size [ 62 , 65 ].…”

“…It is suggested that HER-2 plays a role in tumor proliferation in canines, but not necessarily in malignant transformation [ 62 ]. Various studies confirmed the correlation between HER-2 expression and tumor mitotic index, high histological grade, and size [ 62 , 65 ]. Due to contradictory results in CMT, a recent study was made on quantitative analysis of HER-2 expression by RNA in situ hybridization showing more reliable test results in comparison to immunohistochemistry analysis [ 67 ].…”