Clinical and Laboratory Findings in Dogs Undergoing Adjuvant Chemotherapy with Gemcitabine/Carboplatin Combination for Mammary Neoplasia

Adjuvant chemotherapy might be indicated in some canine mammary cancer cases due to metastatic potential. In this regard, studies to determine adverse events following chemotherapy protocols are valuable. The purpose of this prospective clinical trial was to evaluate the safety and tolerability of gemcitabine and carboplatin combination in dogs with malignant mammary tumors. For this prospective clinical trial, 21 female dogs mastectomized due to malignant mammary neoplasia underwent adjuvant chemotherapy with gemcitabine (3 mg/kg, 60-minute IV infusion) and carboplatin (10 mg/kg, 20-minute IV infusion) based protocol every 21 days for three cycles. They were monitored periodically for treatment-related adverse events by clinical and laboratory evaluations. A total of 17 (80.9%) dogs developed leukopenia, 10 (47.6%) neutropenia, and 15 (71.4%) thrombocytopenia at least once along with the three chemotherapy cycles. All these hematologic toxicities were grade 1, 2, or 3. Two (9.5%) animals had evidence of gastrointestinal toxicity; however, clinical signs were mild to moderate (grades 1 and 2). No dog had life-threatening adverse events (grade 4) or even died (grade 5) of treatment-related complications. The adjuvant chemotherapy protocol with gemcitabine and carboplatin was well-tolerated and safe in female dogs for mammary cancer treatment with self-limiting hematological and gastrointestinal adverse events.

Consensus Regarding the Diagnosis, Prognosis and Treatment of Canine and Feline Mammary Tumors - 2019

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.

Relationship of obesity with clinical and laboratory changes in female dogs with mammary neoplasia

ABSTRACT: Obesity may be associated with the onset of mammary tumors in women. In companion animals, these data are still scarce, mainly associating the clinic of the patient with laboratory and histological findings. This study aimed to evaluate the clinical and laboratory aspects of female dogs with mammary neoplasia, investigating whether they are related to obesity. Four groups of spayed or non-spayed female dogs were studied, divided into (G1) female dogs without mammary tumor and normal body condition score (BCS), (G2) female dogs without mammary tumor and obese, (G3) female dogs with mammary tumor and normal BCS and (G4) female dogs with mammary tumor and obese. BCS, canine body mass index (CBMI), blood count, glucose, total cholesterol, triglycerides and cytopathological and histopathological examinations were evaluated. Mixed-breed animals were the most prevalent in this study (67.5%). There was a limitation regarding the use of CBMI related to body proportionality. Considering the 28 tumors evaluated, carcinoma in mixed tumor was the most prevalent malignant histological type, while adenomyoepithelioma was the most prevalent benign histological type. It was possible to conclude that obesity was not related to clinical and laboratory changes in the female dogs affected with mammary neoplasias. In addition, no relationship was noted between BCS and CBMI with the histological type or malignancy of mammary neoplasia, since the malignant histological types were the most prevalent tumors in both the ideal score group and the overweight to obese group.

Relationship Between the Immunodetection of Alpha-Smooth Muscle Actin and the Aggressiveness of Mammary Papillar Tumors in Female Dog

Papillary carcinoma is a mammary neoplasia of women and female dogs characterized by papillary fibrovascular projections lined by epithelial cells. Evaluation on the biology of these tumors can be done by immunohistochemistry through detection of alpha-smooth muscle actin protein in the papillary myoepithelium, which lacks such a molecule during malignant proliferations. Thus, this study aimed at determining the malignancy degree of papillary mammary tumors of female dogs by immunohistochemistry. Twenty samples of mammary neoplastic tissues collected from female dogs treated in the Veterinary Hospital at FCAV were evaluated by Hematoxylin and Eosin staining (H&E) and tumor cells were immunolabelled with monoclonal antibody to alpha-smooth muscle actin (α-SMA). Five out of 20 cases showed positive immunolabeling greater than 10% of the total immunolabeling. The remaining fourteen cases presented immunostaining lesser than 10% showing decrease or absence of α-SMA labeling in the myoepithelium of the papilla tumors. All those cases in which immunostained cell was over 10% of the neoplasm (5 immunostains of 20 total cases) were classified as benign whereas those below 10% of immunostained in the slid were considered as malignant. Therefore, immunohistochemistry played an essential role in differentiating benign and malignant papillary tumors of bitches as already described for female. Tumor classification by conventional methods, such as H&E staining, can lead to erroneous interpretations on the real biological behavior of the papillary mammary tumor.

Tubulopapillary Carcinoma of the Mammary Gland in a Mare

Background: Mammary gland neoplasia are often observed in bitches and cats, rarely in cows, goats, sheep, sows, and mares. Among the neoplasia that affect mares, breast tumors are rare, as they occur more frequently in older animals. In horses, mammary gland tumors occur more frequently in older animals. In this species there are reports of cases describing carcinomas and adenocarcinomas and several subtypes. Mammary neoplasms in equines tend to be locally aggressive and promote metastases to the regional lymph nodes and other organs, including the lungs, and may cause pleural effusion. The aim objective of the present case report was to describe the clinical-pathological and immunohistochemical findings of a tubulopapillary carcinoma of the mammary gland in mare.Case: Was received a biopsy of a tumor mass of the mammary gland of a 15-year-old Quarter Horse mare. According to the veterinarian, the mare presented an increase in volume with ulceration of the mammary gland three months before the biopsy. Macroscopically, the mass was firm to the cut with white surface measuring 12x12 cm. The fragment was fixed in 10% formalin, routinely processed for histology, paraffin embedded, and stained with hematoxylin and eosin. Microscopically, we observed proliferation of epithelial neoplastic cells arranged in tubules and papillary projections, some with two to three layers of cells. Neoplastic cells had oval, moderate and distinct cytoplasm. The nuclei were rounded with dense chromatin and an apparent nucleolus. There were two figures of mitosis per field of high magnification. Proliferation of neoplastic cells invaded adjacent tissues, and in lymph vessels of the region, neoplastic cells were observed as well as inflammation in adjacent tissue. In addition, the breast fragment was submitted to the immunohistochemistry technique using anti-pancytokeratin and anti-vimentin antibody. In immunohistochemistry for pancytokeratin, there was immunoreactivity with marked cytoplasm in neoplastic epithelial cells. In immunohistochemistry for vimentin, there was cytoplasmic labeling in cells of the supporting tissue (fibroblasts and endothelial cells). After approximately six months of the initial diagnosis, the mare died.Discussion: The diagnosis of tubulopapillary carcinoma of the mammary gland in a mare was based on the clinical-pathological and immunohistochemical findings. In mares, descriptions of breasts neoplasia are uncommon and found in animals aged over 12 years. In a study carried out in slaughterhouses in France, with approximately 40,000 horses slaughtered, only 45 breast neoplasms (0.11%) were observed, most of them consisting of carcinomas. In these equines, the absolute incidence of neoplasia of the reproductive system increases with age and tumors generally appear as deep, multifocal, and ulcerating skin nodules. Thus, important differential diagnoses include chronic mastitis and prepartum breast edema. In mares with neoplasia of the mammary gland, unilateral or bilateral volume increase, pain, warm area, redness and suppurative serous discharge are frequently observed. There are also reports of skin ulceration or necrosis. In the present report, the mare showed increased volume of the mammary gland, with focal hyperthermia, fistulated area and serum-blood secretion. The literature suggests a reserved prognosis for any mare presenting mammary neoplasia. Histopathology and immunohistochemistry were fundamental for the diagnosis of tubulopapillary carcinoma of the mammary gland in the present study. Mammary neoplasiss in mares are rare, but should be considered in the diagnosis of mammary pathologies in this species.