Canine mastopathy (Overview)

Keywords: dogs; cystic fibrosis; prognostic markers; obesity; hormonal imbalance


The etiological factors, pathogenesis and clinical and pathomorphological features of mastitis in dogs remain poorly understood, due to isolated, multidirectional studies on a small number of animals. Fibrocystic disease is diagnosed in different species of animals – small domestic, productive and laboratory animals. The clinical signs are not pathognomonic and an atypical course of the disease is possible. The potential role of mastopathy in the development of cancer has been proven, but the pathogenesis of functional dysplasia of mammary tissue, and the internal and external factors that may initiate further neoplastic transformation, remain poorly understood. Mastopathy in bitches is widespread and accounts for 8 to 30% of benign mammary gland neoplasms. Susceptibility varies considerably according to the distribution of breeds in the region. Compared to neoplasms (where the highest incidence is in animals over 7 years of age), mastitis peaks in 5-6-year-old dogs. A hormonal imbalance has been shown to be a direct cause of fibrocystic disease in bitches, and this has been experimentally confirmed in rats. The prognostic significance of estrogen and progesterone receptor expression was clarified. The importance of chronic inflammation in the pathogenesis of fibrocystic disease was shown. A high risk of mastopathy in overweight bitches has been established. Diabetes is a potential risk factor for fibrocystic disease, but further research is needed to clarify the patterns. The prospect for further research is to identify prognostic factors and key biological mechanisms to predict the course of the disease and to develop pathogenetically sound treatment protocols.


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Bilyi, D. D., & Khomutenko, V. L. (2022). Canine mastopathy (Overview). Theoretical and Applied Veterinary Medicine, 10(4), 3-11.