Prognostic Value Of Vascular Invasion In Breast Tumours In She-Dogs (Pilot Study)

Breast tumours are the most common neoplasm in intact she-dogs. However, breast tumours in she-dogs differ significantly in morphological features and biological behaviour, so the definition of prognostic factors is relevant. A study on tumour cell dissemination in breast tumours in she-dogs by migration of these cells into blood and lymphatic vessels depending on their histological characteristics and disease stage was conducted. The study of the problem was performed on the basis of the clinic of modern veterinary medicine “Best” in Zaporizhzhia. She-dogs with breast neoplasms of different ages and breeds were used as objects in the proven absence of signs of metastatic lesions of other organs and tissues, including lungs, abdominal organs and bones. The presence of cancer cells in the vessels was determined by the tumour clots formed by them, fixed to the endothelium. The study revealed the presence of angioinvasion regardless of the clinical stage of the tumour process. In this case, the dissemination of tumour cells by migration into lymphatic vessels was observed only in the second clinical stage of breast tumours. In patients with stage 1 breast cancer in the vast majority of cases (66.7% of patients) angioinvasion is registered in the micropapillary invasive carcinomas (ICD-O code 8507/2). Tumour cells in blood vessels were verified in simple cribriform carcinoma (ICD-O code 8201/3) in more than 80% of she-dogs with stage 3 breast cancer. In contrast to the above groups, in patients with stage 2 cancer, migration of tumour cells into both blood and lymphatic vessels was found. Most often the signs of angio- and lymphoinvasion were found in invasive carcinoma mixed type (ICD-O code 8562/3), tubulopapillary carcinoma (ICD-O code 8503/3), and tubular carcinoma (ICD-O code 8211/3) ‒ in 34.1% and 36.8%, 19.3% and 26.3%, 17.0% and 10.5% of cases, respectively. The obtained results allow predicting the probability of penetration of tumour cells into blood and lymphatic vessels with a high degree of reliability, which in the future can better predict the biological behaviour of breast tumours