Alessandra Estrela-Lima

Histopathological and immunohistochemical assessment of invasive micropapillary mammary carcinoma in dogs: A retrospective study

Invasive micropapillary carcinoma (IMPC) of the mammary gland, despite its rare occurrence in humans and dogs, is an important neoplasm due to its aggressive behaviour. The aim of this study was to evaluate the clinicopathological and immunophenotypical characteristics of IMPC and to determine the overall survival of dogs with this tumour. Of the selected cases, the majority had >3 cm neoplasms (15/19, 78.95%) and lymph node metastases (16/16, 100%), but only two cases (2/9, 22.2%) had distant metastases. The IMPCs were classified as either pure (15/22, 68.18%) or mixed (7/22, 31.82%) types. There was a predominance of moderate histological grade tumours (16 grade II) and the average overall survival was 120 days. Positive immunohistochemical staining for epithelial membrane antigen and negative staining for CD-31, p63 and cytokeratin (CK) AE1AE3 in cystic formations confirmed the micropapillary nature of these neoplasms. A proportion of cases exhibited positive epithelial staining for p63 (4/20, 20%) and CK34βE12 (20/22, 90.9%). Most cases were positive for oestrogen (19/20, 95%) and progesterone (19/20, 95%) receptors, but lacked HER-2 (16/22, 72.72%) and epidermal growth factor receptor (15/22, 68.18%) over-expression. The mean proliferation index was 14.8%. The findings demonstrate that, similar to humans, canine IMPCs behave aggressively with high rates of metastasis to regional lymph nodes and short overall survival times.

Versican expression in canine carcinomas in benign mixed tumours: is there an association with clinical pathological factors, invasion and overall survival?

BackgroundComponents of the extracellular matrix have been studied in an attempt to elucidate the mechanisms involved in the biological behaviour of tumours. The presence of the proteoglycan versican has been strongly associated with cancer development and progression. However, relationship between versican expression and clinical pathological factors and overall survival has not been previously studied in veterinary medicine. Carcinomas in benign mixed tumours (CBMTs) are one of the most common malignant tumours in female canines and can serve as models for studies of tumour progression. The aim of this study was to evaluate the expression of versican in in situ and invasive carcinomatous areas of canine CBMTs and to evaluate possible associations of versican expression with other classic prognostic factors and overall survival.ResultsClinical staging; histological grade determination; immunohistochemical staining for versican, E-cadherin and Ki-67; and confirmation of invasion areas by staining for p63 and smooth muscle α-actin (α-SMA) were performed on 49 canine cases of CBMT. Tumour invasion was considered when suspicious Haematoxylin-Eosin (HE)-stained areas showed a total loss of α-SMA and p63 immunoreactivity. Versican immunoreactivity was less intense in the areas adjacent to the in situ carcinomatous regions, compared to invasive regions, which showed extensive and strong staining.ConclusionsOur data reveal that in canine CBMTs, versican expression differs significantly between invasive and in situ areas, suggesting a role for this molecule in tumour progression. Although a direct relationship exists between versican and invasiveness, our results indicate that the isolated evaluation of this proteoglycan does not represent an independent prognostic factor in canine CBMTs.

Tear production, intraocular pressure and conjunctival microbiota, cytology and histology of New Zealand rabbits (Oryctolagus cuniculus)

The purpose of this study was to establish reference values for selected ophthalmic diagnostic tests in New Zealand rabbits (Oryctolagus cuniculus). A total of 22 adult male rabbits were used. The ophthalmic tests included evaluation of tear production with Schirmer tear test 1(STT1) and Endodontic absorbent paper point tear test (EAPPTT) using two different commercial brand materials. Applanation tonometry, Culture of the conjunctival bacterial flora, , conjunctival cytology and conjunctival histology were also performed. Mean (±SD) for STT1, EAPPTTa, EAPPTTb and IOP was 7.27±2.51mm/min, 12.43±1.69mm/min, 15.24±2.07mm/min, 12.89±2.80mm Hg, respectively. Staphylococcus epidermidis, Staphylococcus sp. and Bacillus sp. were predominant. The cytological evaluation revealed the presence columnar epithelial cells, superficial squamous keratinized cells, lymphocytes, heterophils, red blood cells, mucus and bacteria. The histological analysis revealed a stratified epithelium, characterized by the presence of columnar epithelial cells with a large number of goblet cells. The reported data can be used for therapeutic or experimental purposes.

HER-2 and EGFR mRNA expression and its relationship with versican in malignant matrix-producing tumors of the canine mammary gland

Versican expression promotes tumor growth by destabilizing focal cell contacts, thus impeding cell adhesion and facilitating cell migration. It not only presents or recruits molecules to the cell surface, but also modulates gene expression levels and coordinates complex signal pathways. Previously, we suggested that the interaction between versican and human epidermal growth factor receptors may be directly associated with tumor aggressiveness. Thus, the expression of EGFR and HER-2 in these neoplasms may contribute to a better understanding of the progression mechanisms in malignant mammary tumors. The purpose of this study was to correlate the gene and protein expressions of EGFR and HER2 by RNA In Situ Hybridization (ISH) and immunohistochemistry (IHC), respectively, and their relationship with the versican expression in carcinomas in mixed tumors and carcinosarcomas of the canine mammary gland. The results revealed that EGFR mRNA expression showed a significant difference between in situ and invasive carcinomatous areas in low and high versican expression groups. Identical results were observed in HER-2 mRNA expression. In immunohistochemistry analysis, neoplasms with low versican expression showed greater EGFR immunostaining in the in situ areas than in invasive areas, even as the group presenting high versican expression displayed greater EGFR and HER-2 staining in in situ areas. Significant EGFR and HER-2 mRNA and protein expressions in in situ carcinomatous sites relative to invasive areas suggest that these molecules play a role during the early stages of tumor progression.

Versican expression in myoepithelial cells from carcinomas in canine mixed mammary tumors

The matrix of canine mixed mammary tumors (CMMTs) consists of proliferating spindle cells of possible myoepithelial origin, as well as myxomatous tissue, cartilage matrix and/or bone. Among the multiple components of this tumor extracellular matrix, versican probably plays a prominent role due to its importance in tumor progression, cell proliferation and differentiation. However, there are few data related to a possible association between versican expression and the state of myoepithelial cell differentiation in CMMTs. Using immunohistochemistry and histochemistry, the objective of this study was to evaluate the expression of versican, sulfated proteoglycans and mucopolysaccharides in myoepithelial cells at different stages of differentiation and to explore a potential relationship with p63 and α-smooth muscle actin (SMA) expression. A significant difference in versican expression was observed among the different stages of myoepithelial cell differentiation with an inverse correlation between versican and p63/SMA expression. These results suggest that at an early stage of proliferation, myoepithelial cells acquire a phenotype consistent with a role in chondrogenesis. Moreover, myoepithelial cells showed an affinity for safranin and periodic acid-Schiff staining at different stages of proliferation supporting the myoepithelial origin of spindle cells from CMMTs.

Exophthalmos due to odontogenic intraorbital abscess in Cebus apella

The accumulation of pus in the orbit originating from an infected dental root is classified as odontogenic intraorbital abscess.

Colopexia e deferentopexia associadas à omentopexia no tratamento da hérnia perineal em cães: um estudo de trinta casos

Several surgical techniques have been proposed for perineal hernia correction in dogs and regardless of the used method the surgical risk related to clinical status and animal age should always be considered, since the involvement of the urinary tract and/or digestive tract is frequent and the geriatric patient can present multiple problems that significantly affect their tolerance to anesthesia, surgery and infections. In this context, this study aimed to evaluate the use of colopexy and deferentopexy associated with omentopexy as surgical alternative in 30 elderly dogs, systemically compromised, which had perineal hernia and concomitant rectal anomaly. The cases analysis showed that the proposed surgical technique allowed the inspection and evaluation of abdominal organs, particularly those with hernial content involved; the distal colon linear format restoration, reducing its diameter and encouraging a normal function return, effective setting and secure cranial prostate and urinary bladder repositioning, avoiding further caudal displacement; satisfactory tissue repair and defect occlusion of the pelvic diaphragm. Thus, it was concluded that the proposed procedure has therapeutic value for dogs with perineal hernia and concomitant rectal sacculation.

Invasive micropapillary carcinoma of the mammary gland in humans and canines: Clinicopathological, immunophenotypical and survival approaches

Invasive micropapillary carcinoma (IMPC) is a breast cancer with a proclivity for lymph node metastasis that affects women. In canines, this carcinoma has only recently been reported and appears to have similar histological aspects as its human counterpart. Thus, the aim of the present study was to compare clinicopathological, immunohistochemical and prognostic characteristics of mammary IMPC between humans and canines. In canines, regional metastasis was more frequently observed. Histopathologically, humans and canines predominantly showed a moderate histological grade. The pure subtype and neoplastic emboli were more frequently observed in canines. Regarding immunohistochemical evaluation, most canine and human IMPCs were positive for the estrogen and progesterone receptors. A reversed pattern of epithelial membrane antigen expression and a high proliferation index predominated in both species. The mortality due to the neoplastic disease was more frequently observed in canines (94%) than in humans (4%). Thus, canine IMPCs show a larger tumor size and higher rates of the pure subtype, regional metastasis and mortality than their human counterparts and appear to provide a good spontaneous model for achieving a better understanding of the biological behavior of human IMPCs.

Ophthalmic parameters of Blue-and-yellow Macaws ( Ara ararauna ) and Lear's Macaws ( Anodorhynchus leari )

Our aim was to determine the ophthalmic parameters and describe the eye histology of Blue-and-yellow Macaws (Ara ararauna) and Lears Macaws (Anodorhynchus leari) kept at the Triage Center for Wild Animals (CETAS) and in Getulio Vargas Zoobotanic Park (Salvador, northeastern Brazil), respectively. Thirty four clinically healthy macaws (28 Blue-and-yellow Macaws and six Lears Macaws) were studied. The investigation included culture of the conjunctival bacterial flora, evaluation of tear production by endodontic absorbent paper point tear test (EAPPTT) and phenol red thread test (PRTT), measurement of palpebral fissure length (PFL), corneal touch threshold (CTT) and intraocular pressure (IOP), as well as characterisation of conjunctival cytology samples, B-mode ultrasonography, and eye histology of one Blue-and-yellow Macaw. There was a predominance of Gram-positive bacteria in the samples analysed and the microorganism colonies were resistant to tetracycline and oxacillin. Blue-and-yellow Macaws had significantly higher EAPPTT than Lears Macaws, but there were no differences in PFL and IOP. Conjunctival cytology revealed predominance of squamous and columnar epithelial cells. The pecten, a pleated structure located on the optic nerve and projecting into the vitreous, was composed of several large blood vessels and capillaries. The ophthalmic parameters determined in this study may help in the diagnosis of ocular diseases in Blue-and-yellow and Lears Macaws.

The effect of naltrexone as a carboplatin chemotherapy-associated drug on the immune response, quality of life and survival of dogs with mammary carcinoma

The objective of this study was to evaluate the effect of low-dose naltrexone (LDN) as a carboplatin chemotherapy-associated drug in female dogs with mammary carcinoma in benign mixed tumors (MC-BMT) after mastectomy and to assess its association with quality of life and survival rates. Sixty female dogs were included in this study, all of which had histopathological diagnosis of MC-BMT and were divided into three groups: G1 (control), consisting of animals submitted only to mastectomy with or without regional metastasis; G2, composed of treated animals that did not present with metastasis; and G3, treated dogs that presented with metastasis. G2 and G3 were also subdivided according to the treatment administered: chemotherapy alone (MC-BMT(-) C/MC-BMT(+) C) or LDN and chemotherapy (MC-BMT(-) C+LDN/MC-BMT(+) C+LDN). All animals were subjected to clinical evaluation, mastectomy, peripheral blood lymphocyte immunophenotyping, beta-endorphin and met-enkephalin quantification, and evaluation of survival rates and quality of life scores. The results showed higher serum concentrations of beta-endorphin and met-enkephalin, fewer chemotherapy-related side effects, and better quality of life and survival rates in the LDN-treated groups than in LDN-untreated groups (P < 0.05). Evaluation of clinical and pathological parameters indicated a significant association between the use of LDN and both prolonged survival and enhanced quality of life. These results indicate that LDN is a viable chemotherapy-associated treatment in female dogs with MC-BMT, maintaining their quality of life and prolonging survival rates.