The aim of this paper is to discuss and update criteria that can guide the diagnosis, prognosis and treatment of canine and feline mammary neoplasms. It was elaborated during the IV Mammary Pathology Meeting: Diagnosis, Prognosis and Treatment of the Canine and Feline Mammary Neoplasia, held on April 29th and 30th, 2019 in Belo Horizonte – MG, Brazil, sponsored by the Laboratory of Comparative Pathology of the Federal University of Minas Gerais (UFMG), with the support of the Brazilian Association of Veterinary Pathology (ABPV) and Brazilian Association of Veterinary Oncology (ABROVET). Academics from several regions of Brazil were present and contributed to this work.

No abstract

No abstract

BackgroundThe antibody Ki-67 is a reliable and easy tool to accurately assess the growth fraction of neoplasms in humans and animals, and it has been used to predict the clinical outcome. Therefore, the aim of the present study was to investigate the immunohistochemical expression pattern of Ki-67 in normal and neoplastic perianal glands of dogs to evaluate the possible use of this proliferation marker as an ancillary method of perianal tumor diagnosis. We studied 42 cases of perianal gland neoplasms including adenomas (n = 15), epitheliomas (n = 15), and carcinomas (n = 12). As controls, 13 tissue samples from normal perianal glands were used. A Ki-67 index was established by a computer-assisted image analysis and compared with manual counting.ResultsOut of the 42 cases of perianal gland neoplasms, 34 were from males and eight from females. Recurrence was reported in 14 cases, being higher (8/12) in carcinomas. Immunostaining for Ki-67 revealed that the carcinomas showed a higher proliferation rate (9.87%) compared to groups of epitheliomas (2.66%) and adenomas (0.36%). For adenomas and epitheliomas of the perianal glands the computer-assisted counting and the manual counting gave similar results; however, only the computer-assisted image analysis was efficient to predict the perianal gland carcinoma recurrence.ConclusionSince there were significant differences in the number of Ki-67-positive nuclei, this marker proved to be effective in helping the classification of perianal gland neoplasms and to refine the diagnosis criteria, especially in those samples with high variation in morphology/area. Also, higher Ki-67 index is related to recurrence in cases of perianal gland carcinomas. Further, the computer-assisted image analysis proved to be a fast and reliable method to assess the Ki-67 index in perianal gland neoplasms.

A apoptose e a proliferação celular possuem uma participação importante na tumorigênese, determinando o crescimento tumoral e consequentemente sua agressividade. O presente estudo teve como objetivo avaliar a ocorrência da apoptose associada a proliferação celular em neoplasias mamárias em cadelas e a elas a evolução clínica do paciente. Setenta animais foram submetidos à exérese cirúrgica do tumor, sendo este submetido ao diagnóstico histopatológico e marcação imuno-histoquímica para caspase-3 e Ki-67. Estes marcadores de apoptose e proliferação celular demonstraram grande expressão nas neoplasias malignas, principalmente nos carcinomas, considerado o mais maligno dos tumores. Estes resultados corroboram os dados da literatura e contribuem para um prognóstico tumoral criterioso que complementa a classificação tumoral existente proporcionando uma melhor e maior sobrevida devido a uma adequação do procedimento terapêutico de cada paciente.

Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma in dogs. We evaluated Ki67 immunoexpression and mitotic index (MI) in dogs diagnosed with DLBCL and treated with a 19-wk CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) protocol. Twenty-nine lymph node samples from dogs diagnosed with DLBCL were analyzed for Ki67 immunostaining, and positive cells present in 1 cm were counted in a grid reticle for comparison of survival times above and below the means. The Ki67 mean was 107, and the MI mean was 21. There was a significant ( p < 0.05) difference in median survival time between Ki67 immunostaining above and below the mean, with no difference in MI groups. Ki67 values >107 positive cells per 5 HPF counted in a grid reticle were associated with shorter survival times in dogs with DLBCL treated with a 19-wk CHOP-based protocol.

No abstract

Mast cell tumors (MCTs) are hematopoietic neoplasms composed of mast cells. It is highly common in dogs and is extremely important in the veterinary oncology field. It represents the third most common tumor subtype, and is the most common malignant skin tumor in dogs, corresponding to 11% of skin cancer cases. The objective of this critical review was to present the report of the 2nd Consensus meeting on the Diagnosis, Prognosis, and Treatment of Canine Cutaneous and Subcutaneous Mast Cell Tumors, which was organized by the Brazilian Association of Veterinary Oncology (ABROVET) in August 2021. The most recent information on cutaneous and subcutaneous mast cell tumors in dogs is presented and discussed.