Resultado da pesquisa (62)

Termo utilizado na pesquisa neoplasm

#1 - Clinical, pathological and immunohistochemical characterization of spontaneous neoplasms in pet rodents in Northeastern Brazil

Abstract in English:

In the last decade, there has been a significant increase in the demand for small rodents such as hamsters, guinea pigs, rats, and mice to be kept as pets. Consequently, the veterinary care provided to these animals has also increased. The aim of this study was to describe gross, histopathological and immunohistochemical findings of 26 spontaneous neoplasms diagnosed in 25 pet rodents in Northeastern Brazil. A retrospective study was carried out from 2014 to 2022 in two veterinary diagnostic laboratories to identify cases of tumoriform lesions in these species. Hamsters represented the most frequent species in this study (60%, 15/25), followed by rats (28%, 7/25), guinea pigs (8%, 2/25), and mice (4%, 1/25), with a mean age of 17.63 months. The anatomical regions of the face/head and thoracic region were the most affected. The most affected tissues were the skin/subcutaneous/mucosal (65%, 15/26) and mammary gland (23%, 6/26). Eighteen different types of neoplasms were diagnosed, and T-cell lymphomas and mammary adenocarcinomas were the most diagnosed tumors, each corresponding to 12% (3/26) of the cases. Leiomyosarcoma, myxosarcoma and mammary adenocarcinoma metastases were also noted. Immunohistochemistry was essential for the diagnosis of certain malignant mesenchymal and round-cell neoplasms. Pet rodent neoplasms in Northeastern Brazil are common, especially in hamsters, and immunohistochemistry can be a useful tool for the definitive diagnosis of these tumors.

Abstract in Portuguese:

In the last decade, there has been a significant increase in the demand for small rodents such as hamsters, guinea pigs, rats, and mice to be kept as pets. Consequently, the veterinary care provided to these animals has also increased. The aim of this study was to describe gross, histopathological and immunohistochemical findings of 26 spontaneous neoplasms diagnosed in 25 pet rodents in Northeastern Brazil. A retrospective study was carried out from 2014 to 2022 in two veterinary diagnostic laboratories to identify cases of tumoriform lesions in these species. Hamsters represented the most frequent species in this study (60%, 15/25), followed by rats (28%, 7/25), guinea pigs (8%, 2/25), and mice (4%, 1/25), with a mean age of 17.63 months. The anatomical regions of the face/head and thoracic region were the most affected. The most affected tissues were the skin/subcutaneous/mucosal (65%, 15/26) and mammary gland (23%, 6/26). Eighteen different types of neoplasms were diagnosed, and T-cell lymphomas and mammary adenocarcinomas were the most diagnosed tumors, each corresponding to 12% (3/26) of the cases. Leiomyosarcoma, myxosarcoma and mammary adenocarcinoma metastases were also noted. Immunohistochemistry was essential for the diagnosis of certain malignant mesenchymal and round-cell neoplasms. Pet rodent neoplasms in Northeastern Brazil are common, especially in hamsters, and immunohistochemistry can be a useful tool for the definitive diagnosis of these tumors.


#2 - Lesions of the oral cavity of dogs: 720 cases

Abstract in English:

Seven hundred twenty cases of oral cavity lesions in dogs were diagnosed from 2015 to 2020 in Distrito Federal, Brazil. Four hundred thirty-two (60%) lesions were neoplastic, and 288 (40%) were non-neoplastic. Of the neoplasms, 229 (53%) were considered malignant and 203 (47%) benign, affecting mainly males, of 43 different breeds, with an average age of 9.4 years, mainly the gum and lip. Melanoma was the most (96/432, 22.2%) commonly diagnosed neoplasm, followed by peripheral odontogenic fibroma (68/432, 15.7%), papilloma (63/432, 14.5%) and squamous cell carcinoma (SCC) (56/432, 12.9%). Non-neoplastic lesions also affected males predominantly, from 41 different breeds, with an average age of 8.9 years, mainly in the gums, lip, and tongue. These lesions were diagnosed as inflammatory (230/288, 79.8%), hyperplastic (47/288, 16.3%) and other lesions (11/288, 3.8%).

Abstract in Portuguese:

Foram estudados 720 casos de lesões na cavidade oral em cães diagnosticados entre 2015 e 2020, no Distrito Federal. Dessas alterações, 432 (60%) foram neoplásicas e 288 (40%) não neoplásicas. Dentre os neoplasmas, 229 (53%) foram consideradas malignos e 203 (47%) benignos, acometendo principalmente machos, de 43 raças diferentes, com idade média 9,4 anos, afetando principalmente gengiva e lábio. Melanoma foi o neoplasma mais comumente diagnosticado (96/432; 22,2%), seguido do fibroma odontogênico periférico (68/432; 15,7%), papiloma (63/432; 14,5%) e carcinoma de células escamosas (56/432; 12,9%). As lesões não neoplásicas também acometeram predominantemente machos, de 41 raças diferentes, com idade média 8,9 anos, afetando principalmente gengiva, lábio e língua. Essas lesões foram diagnosticadas como inflamatórias (230/288; 79,8%), hiperplásicas (47/288; 16,3%) e como outras alterações (11/288; 3,8%).


#3 - Cytological grading of canine mast cell tumors: correlation with histologic grading and survival time

Abstract in English:

Mast cell tumors are one of the most common neoplasia in dogs and cytopathology and/or histopathology examinations are used for diagnosis. Histologic grading is considered the gold standard test to predict the prognosis of this neoplasia. However, studies have been conducted using the cytological grading system to provide similar information in a faster, less invasive, and more accessible way. This study aimed to investigate cytological graduation and correlate it with histological grading and the survival time of dogs diagnosed with cutaneous mast cell tumors at the Veterinary Hospital of “Universidade Federal de Uberlândia” over five years. For that, cytological and histological slides from 72 animals were reviewed. The statistical methods used were the kappa test for agreement between grading systems, the Kaplan–Meier for survival time, Cox regression for comparison of cytological and histological grades and survival time. The cytological grading when compared to the two-tier histologic grading, high and low grades, had a moderate agreement (kappa 0.566). When the correlation between survival time and the cytological grade was evaluated, there was a higher death rate in the group with high-grade mast cell tumors compared to low grade, pointing to a correlation between survival time and cytological grade (p=0.009). In conclusion, the cytological grade is useful to treatment planning and providing prognostic information that precedes tumor removal, showing a good correlation with the two-tier histologic grading and with the survival time of the animals.

Abstract in Portuguese:

O mastocitoma é uma das neoplasias cutâneas mais comum nos cães e os exames citopatológicos e/ou histopatológicos são utilizados para diagnóstico. A graduação histológica é considerada padrão ouro para prever o prognóstico dessa neoplasia. Contudo, estudos têm sido realizados visando utilizar graduação citológica para fornecer informações semelhantes de maneira rápida, menos invasiva e mais acessível. Esse trabalho objetivou realizar graduação citológica e correlacionar com as graduações histológicas e com a sobrevida de cães diagnosticados com mastocitoma cutâneo no Hospital Veterinário da Universidade Federal de Uberlândia durante 5 anos. Para isso, lâminas de citologia e histologia de mastocitomas de 72 animais foram revisadas. Os métodos estatísticos utilizados foram teste kappa para concordância entre os sistemas de graduação, método Kaplan-Meier para tempo de sobrevida dos animais, e análise pela regressão de Cox para comparação do grau citológico e grau histológico e o tempo de sobrevida global. A graduação citológica quando comparada com a histológica de dois níveis, alto grau e baixo grau, obteve uma concordância moderada (kappa 0,566). Na avaliação da correlação entre sobrevida e grau citológico, houve maior taxa de óbito no grupo de cães com mastocitoma de alto grau, comparado aos de baixo grau, sendo observada correlação entre a sobrevida e o grau citológico (p=0,009). Esse estudo concluiu que o grau citológico é útil para o planejamento do tratamento e para fornecer informações prognósticas que antecedem a exérese do tumor, tendo boa correlação com a graduação histológica de dois níveis e com a sobrevida dos animais.


#4 - Epidemiological, clinical, and therapeutic aspects of canine transmissible venereal tumor in Rio de Janeiro, Brazil (2015-2020)

Abstract in English:

Canine transmissible venereal tumors (TVT) have a high incidence in Brazil. This is partly due to the large population of stray dogs and the ineffectiveness of epidemiological control programs. This study aimed to describe the epidemiological data, clinical manifestations, and treatments used in dogs affected by TVT. Data were retrospectively collected from the 2015-2020 records of the Veterinary Hospital of the Federal Rural University of Rio de Janeiro. A total of 252 dogs were diagnosed with TVT during the study period. Of these, 81.3% were mixed-breed, 50.4% were males, and 88.9% were young or adult animals. The genital region only was affected in 77.3% of cases. Exclusively extragenital lesions were observed in 22.6% of cases. Among the animals seen, 40.1% received no treatment. Of those treated, 99.3% underwent a vincristine sulfate protocol, and in 77.2%, the treatment resulted in total remission of the neoplasm after 4 to 6 chemotherapy sessions. It was concluded that TVT is a neoplasm most often seen in mixed-breed dogs and located in the genital region, with hemorrhagic secretion being the main clinical sign reported by owners. Vincristine sulfate is currently the most used therapy, with high efficacy. However, despite the good prognosis, there was a high rate of non-adherence or abandonment of treatment, and this is an important factor to be considered and addressed by veterinarians.

Abstract in Portuguese:

O tumor venéreo transmissível (TVT) apresenta elevada incidência no Brasil, relacionada a elevada população de caninos errantes e a ineficácia dos programas de controle epidemiológicos. O objetivo do estudo foi descrever dados epidemiológicos, manifestação clínica e o tratamento empregado em cães acometidos pelo TVT no Hospital Veterinário da Universidade Federal Rural do Rio de Janeiro entre os anos de 2015 e 2020. Foram diagnosticados 252 cães com TVT durante o período do estudo, sendo 81,3% cães sem raça definida, 50,4% machos e 49,6% fêmeas, e com 88,9% animais jovens ou adultos. A região genital foi acometida em 77,3% dos casos. Lesões exclusivamente extragenitais foram observadas em 22,6% dos casos. Quanto ao tratamento, 40,1% dos cães não receberam tratamento. Entre os animais tratados, 99,3% utilizaram protocolo com sulfato de vincristina e em 77,2% o tratamento resultou em remissão total da neoplasia, com a realização de 4 a 6 sessões do quimioterápico. Conclui-se que o TVT é uma neoplasia frequentemente relacionada a cães sem raça definida, localizados na região genital, com secreção hemorrágica sendo o principal sinal clínico reportado pelos proprietários. O sulfato de vincristina é a terapia mais empregada, com alta eficácia. Entretanto, apesar de ser uma neoplasia com bom prognóstico, o alto índice de não adesão ou abandono ao tratamento representa um importante fator a ser considerado e trabalhado pelos médicos veterinários.


#5 - Retrospective evaluation of canine anal sac carcinoma (260 cases) in Brazil: late detection and failures in lymph node evaluation

Abstract in English:

Anal sac neoplasms are common in companion animals, and the epidemiological profile has been extensively described in international studies; however, national data are still lacking. Data on the Brazilian reality of anal sac carcinoma cases’ diagnosis and treatment are also scarce. The purpose of this study was to retrospectively evaluate cases of canine anal sac carcinoma and assess the profile of involvement, tumor size, and lymphatic invasion at the time of diagnosis. Information was obtained from Vetpat laboratory database, from 260 cases spanning a 12-year period (2010-2021). In histopathological evaluation at the time of diagnosis, data on sex, age, and race were described, as well as tumor size and lymphatic invasion. The presence of metastasis was also assessed in cases where lymph nodes were sampled. Simple descriptive statistical analysis was used to evaluate the data. Adult and elderly, female, and mixed-breed animals were more involved, indicating differences from international studies that can be attributed to sociocultural factors. In terms of tumor size, it was observed that 93% of the cases had the largest diameter above 2.5cm. Only 7% of the cases had the largest diameter below 2.5cm, demonstrating the often late diagnosis and the importance of rectal palpation examination during the general physical assessment of canine patients, particularly at an advanced age. Regarding lymphatic invasion and affected lymph nodes, 50% of the cases had lymphatic invasion described in the histopathological examination. However, only 5% of the lymph nodes were sent along with the primary tumor, indicating the disease’s aggressive behavior but with possible metastases underdiagnosed.

Abstract in Portuguese:

As neoplasias de saco anal possuem incidência importante nos animais de companhia, tendo o seu perfil epidemiológico de acometimento amplamente descrito em estudos internacionais, entretanto dados nacionais ainda são escassos. De modo semelhante, dados acerca da realidade brasileira, associados ao diagnóstico e conduta desses casos, são inexistentes. O objetivo do presente trabalho foi avaliar, de forma retrospectiva, os casos de carcinoma de saco anal canino, avaliando o perfil de acometimento, o tamanho tumoral e a invasão linfática no momento do diagnóstico. Foi obtido informações de 260 casos, respectivo a um período de 12 anos (2010-2021), proveniente do banco de dados do laboratório Vetpat. Foram descritos os dados acerca do sexo, idade e raça, bem como o tamanho tumoral e presença de invasão linfática em avaliação histopatológica no momento do diagnóstico. Os casos que cursavam com envio dos linfonodos também foram avaliados quanto a presença de metástase. Os dados foram avaliados mediante análise estatística descritiva simples. Foi encontrado um maior acometimento em animais adultos a idosos, do sexo feminino e sem raça definida, evidenciando diferenças em relação a estudos internacionais, que podem ser atribuídas a fatores socioculturais. Em relação ao tamanho tumoral, observou-se que 93% dos casos apresentavam o maior diâmetro acima de 2,5cm e apenas 7% dos casos apresentavam o maior diâmetro abaixo de 2,5cm, evidenciando o diagnostico frequentemente tardio, bem como a importância do exame de palpação retal durante a avaliação física geral de pacientes caninos, principalmente em idade avançada. Quanto a avaliação da invasão linfática e linfonodos acometidos, 50% dos casos cursavam com invasão linfática descrita em exame histopatológico, entretanto em apenas 5% dos casos os linfonodos foram enviados junto ao tumor primário, evidenciando o comportamento agressivo da doença, porém com metástases possivelmente subdiagnosticadas.


#6 - A comparative analysis of anatomopathological features and COX-2 expression of mammary neoplasms with malignant mesenchymal components in female dogs

Abstract in English:

Canine mammary neoplasms with malignant mesenchymal components, such as carcinosarcomas and sarcomas, belong to an uncommon and histologically heterogeneous group. Little is known about the biological behavior of these histogenic variants. This study aimed to compare the clinicopathological characteristics and the COX-2 immunohistochemical expression of different histologic subtypes of carcinosarcomas and sarcomas. Samples of 23 carcinosarcomas and 15 sarcomas from the mammary glands of female dogs were studied. Medical records were reviewed to obtain clinical data. Subsequently, histology microscope slides were analyzed to assess for mesenchymal subtypes, necrosis, vascular invasion, histologic grades, and lymph node metastasis. Immunohistochemistry was used to assess the COX-2 expression. The malignant mesenchymal proliferation was categorized into osteosarcomas (23/40), fibrosarcomas (5/40), liposarcomas (6/40) and chondrosarcomas (4/40). The osteosarcomatous differentiation was the most predominant type among the sarcomas and carcinosarcomas and was associated with vascular invasion (P=0.010) and lymph node metastases (P=0.014). High COX-2 expression was detected in 14.3% of the carcinosarcomas (carcinoma and/or sarcoma cells) and 27.3% of the sarcomas. The carcinosarcomas and sarcomas had similar clinical and pathological characteristics and developed as large tumors, with intratumoral necrosis and a predominance of high histologic grades, although the frequency of vascular invasion and lymph node metastasis was low. Osteosarcoma subtypes presented more aggressive characteristics than non-osteosarcoma subtypes.

Abstract in Portuguese:

Neoplasias mamárias caninas com componentes mesenquimais malignos, como carcinossarcomas e sarcomas, são um grupo de neoplasias pouco frequentes e histologicamente heterogêneas e pouco se sabe sobre o comportamento biológico das variantes histogênicas. O objetivo desse estudo é comparar as características anatomopatológicas e a expressão imunoistoquímica de COX-2 de diferentes subtipos histológicos de carcinossarcomas e sarcomas. Foram estudados 23 carcinosarcomas e 17 sarcomas da glândula mamária de cadelas. Os prontuários médicos foram revisados para obtenção de dados clínicos. Posteriormente, as lâminas histológicas foram avaliadas para acessar os subtipos mesenquimais, necrose, invasão vascular, grau histológico, metástase linfonodal. A imunoistoquímica foi realizada para avaliar a expressão de COX-2. Os tipos encontrados de proliferação mesenquimal maligna foram osteossarcoma (23/40), fibrossarcoma (7/40), lipossarcoma (6/40) e condrossarcoma (4/40). A diferenciação osteossarcomatosa foi predominante entre os sarcomas e carcinossarcomas e foi associado com invasão vascular (P=0,006) e metástase linfonodal (P=0,014). Uma expressão alta de COX-2 foi detectada em 14,3% dos carcinossarcomas (células carcinomatosas e/ou sarcomatosas) e 27,3% dos sarcomas. Os carcinossarcomas e sarcomas apresentaram características clínicas e patológicas semelhantes e se desenvolveram como tumores grandes, com necrose intratumoral e predomínio de alto grau histológico, mas com baixa frequência de invasão vascular e metástase distante. Os subtipos osteossarcomatosos apresentaram características mais agressivas quando comparados com subtipos não osteossarcomatosos.


#7 - Ocurrence enzootic hematuria in buffaloes in Brazil: epidemiological, clinical, and pathological aspects

Abstract in English:

It is reported the occurrence of enzootic hematuria (EH) in buffaloes in Brazil after performing an epidemiological survey and clinicopathological analises. To date, EH caused by ingestion of Pteridium esculentum subsp. arachnoideum, a radiomimetic plant popularly known as “bracken fern”, has not been described in this species in Brazil. Bovine EH is responsible for high economic losses in Brazil’s Southeast Region not only because of the deaths it causes, but also owing to its negative effect on productivity. In São José do Barreiro County, São Paulo, some farmers in areas with a high incidence of bovine EH have been replacing cattle with buffaloes, based on the premise that the latter would be more resistant to poisoning by ingestion of Pteridium spp. However, even though initial observations indicated that buffaloes are indeed less sensitive than cattle to the toxic principle of Pteridium spp., cases of hematuria in this species have been reported. According to preliminary date, EH only occurs in buffaloes over six years of age. Macroscopic examination revealed a thickened urinary vesicle mucosa, along with multiple foci of ulcerated, exophytic, verrucous, and pedunculated lesions. In one of the buffaloes studied, the bladder wall was ruptured and exhibited marked secondary inflammation. Histologically, neoplastic and non-neoplastic changes similar to those described in cattle poisoned by Pteridium spp. were observed. The neoplasms found included papilloma, carcinoma in situ, urothelial carcinoma (low and high grade), inverted, microcystic, and trabecular variants, urothelial carcinoma with divergent differentiation (squamous and glandular), squamous cell carcinoma, lymphangioma, hemangioma, and hemangiosarcoma. There was also coexistence of epithelial and mesenchymal neoplasms. Bovine papillomavirus particles were not detected by polymerase chain reaction in the bladder samples analyzed.

Abstract in Portuguese:

Descreve-se, através de levantamento epidemiológico e avaliação clínico-patológica, a ocorrência de hematúria enzoótica (HE) em búfalos no Brasil. Essa condição, causada pela ingestão da planta radiomimética Pteridium esculentum subsp. arachnoideum, conhecida popularmente como “samambaia” ou “samambaia do campo”, até então não havia sido descrita nessa espécie no Brasil. Na Região Sudeste, a HE bovina é responsável por elevadas perdas econômicas, devidas não apenas aos óbitos, mas também em função da queda de produtividade. No município de São José do Barreiro/SP, alguns produtores de áreas com alta incidência de HE bovina, vêm substituindo os bovinos por búfalos, com base na premissa de que estes seriam mais resistentes à intoxicação. Embora, de acordo com observações iniciais, os búfalos realmente sejam menos sensíveis que os bovinos ao princípio tóxico de Pteridium spp., ainda assim, tem-se verificado a ocorrência de casos de hematúria nessa espécie. De acordo com o levantamento inicial, a HE só ocorre em búfalos com idade a partir de seis anos. Ao exame macroscópico, verificou-se a mucosa da bexiga espessa, com múltiplos focos de lesões ulceradas, exofíticas, papiliformes, verrucosas, pedunculadas. Histologicamente, foram observadas alterações neoplásicas e não neoplásicas semelhantes às descritas nos bovinos com HE. Entre as neoplasias foram encontrados papiloma, carcinoma in situ, carcinoma urotelial (baixo e alto grau), variantes invertida, microcística e trabecular, carcinoma urotelial com diferenciação divergente (escamosa e glandular), carcinoma de células escamosas, linfangioma, hemangioma e hemangiossarcoma. Ocorreu também coexistência entre neoplasias epiteliais e mesenquimais. Não foram detectadas partículas de papilomavírus bovino pelo teste PCR nas amostras de bexiga analisadas.


#8 - Complications after cerebrospinal fluid collection in dogs with brain neoplasm

Abstract in English:

Cerebrospinal fluid (CSF) collection in dogs with brain neoplasms (BN) may be associated with complications owing to increased intracranial pressure caused by expansive lesions. Although this procedure has been performed in dogs with BN, no data regarding complications after CSF tap in these animals is available. Thus, this retrospective study aimed to identify the rate and types of complications observed after CSF taps in dogs with BN. Thirty dogs with BN were included in the study. In 83% (25/30) of the cases, clinical recovery after CSF tap was considered normal, and in 17% (5/30) the recovery was abnormal. The main clinical and neurological signs observed in dogs with abnormal clinical recovery were apnea (5/5), absence of pupillary photomotor reflex (3/5), coma (2/5), and stupor (1/5). In 40% (2/5) of the dogs, herniation of the cerebellum through the foramen magnum was observed on necropsy. In conclusion, the rate of complications after CSF taps was 17%, and was characterized by apnea, absent pupillary photomotor reflex, altered level of consciousness, and encephalic herniation.

Abstract in Portuguese:

A colheita do líquido cerebroespinhal (LCE) em cães com neoplasmas encefálicos (NE) pode estar associada a complicações devido ao aumento da pressão intracraniana (PIC), causada pela lesão expansiva. Embora o procedimento seja realizado em cães com NE, não foram encontrados dados referentes às complicações após colheita de LCE nesses pacientes. Sendo assim, o objetivo do presente estudo retrospectivo foi identificar a taxa, bem como os tipos de complicações observadas após a colheita de LCE em cães com neoplasma encefálico. Dos 30 cães com NE incluídos no estudo, em 83% (25/30) dos casos a evolução clínica após a colheita do LCE foi considerada normal e, em 17% (5/30) anormal. Os principais sinais clínicos e neurológicos observados nos cães com evolução clínica anormal foram apneia (5/5), reflexo fotomotor pupilar ausente (3/5), coma (2/5) e estupor (1/5). Em 40% (2/5) foi observado herniação do cerebelo na necropsia. Com base nos resultados encontrados, conclui-se que a taxa de complicações após a colheita de LCE foi baixa (17%) e as alterações encontradas foram apneia, seguido de reflexo fotomotor pupilar ausente, alteração no nível de consciência e herniação encefálica.


#9 - Oxidative stress in female dogs with mammary neoplasms

Abstract in English:

The result of the reaction of free radicals with biomolecules is the formation of substances with the potential of inducing oxidative damage, a condition known as oxidative stress. There are voluminous literature data reporting the association, both as a cause and as a consequence, between different diseases and oxidative stress. In this study, 144 female dogs with mammary neoplasia were analyzed. The animals were submitted to clinical evaluation for disease staging, hematological evaluation, serum biochemistry (renal and hepatic function tests), and dosage of the oxidative damage biomarker, malondialdehyde (MDA), at the time of its approach and 30 days after treatment. A control group of 100 healthy animals was also submitted to determination of serum MDA levels. The mean age of the animals affected by mammary neoplasms was 9.88±2.95 (4 to 14) years, while in healthy animals it was 2.31±1.90 years (1 to 6). Of the 144 animals, 113 (78.9%) had malignant neoplasms, and 15, 21, 46, 17 and 14 animals were in clinical stage I, II, III, IV and V respectively and the carcinoma in a mixed tumor was the most frequent histological pattern in this group (26%). Thirty-one animals were diagnosed with benign neoplasms and mammary adenoma was the most frequent histological pattern in 15 animals (51.61%). Hematological changes in the preoperative period were observed in 44 (38.9%) and 12 (38.7%) animals with malignant and benign neoplasias, respectively, and there was a positive correlation between anemia and higher levels of MDA (P=0.0008) for animals with malignant tumors. Regarding serum biochemical parameters, the most frequent alterations in animals with malignant neoplasms were elevated ALT levels in 12 animals (10.6%), creatinine in 10 animals (8.84%) and urea in eight animals (7.07%). Females with benign neoplasms presented less occurrence of changes in these parameters. In the group of healthy animals (control), the mean serum MDA values were 12.08±4.18, whereas in the pre-treatment group, mean MDA was 24.80±5.74 for bitches with benign neoplasms and 32.27±10.24 for bitches with malignant tumors. A significant increase (P<0.001) in MDA levels was observed in animals with malignant mammary neoplasms when compared to healthy animals and with benign tumors. In addition, a significant reduction (P<0.001) was observed 30 days after treatment in MDA levels (27.37±7.86) in animals with malignant tumors. In conclusion, our results indicate an association between MDA seric levels and mammary neoplasms in dogs. The results suggest that this factor can be used as a biomarker of oxidative stress with a potential impact in the prognostic of mammary tumors, since significantly higher levels of MDA were detected especially in dogs carrying malignant tumors and presenting anemia.

Abstract in Portuguese:

O resultado da reação de radicais livres com biomoléculas é a formação de substâncias que podem ser utilizadas como marcadores de dano oxidativo, condição mais conhecida como estresse oxidativo. Evidências científicas comprovam a relação, quer como causa, quer como consequência, entre muitas doenças e o estresse oxidativo. Neste estudo, 144 cadelas portadoras de neoplasia de mama, foram submetidas à avaliação clínica para estadiamento da doença, avaliação hematológica, testes de função renal e hepática e dosagem do biomarcador de dano oxidativo, malondialdeído (MDA), no momento de sua abordagem e 30 dias após realização de tratamento. Um grupo controle de 100 cadelas saudáveis foi submetido também à determinação dos níveis séricos de MDA. A idade média dos animais acometidos por neoplasias mamárias foi de 9,88±2,95 (4 a 14) anos, enquanto que nos animais saudáveis foi de 2,31±1,90 anos (1 a 6). Dos 144 animais, 113 (78, 9%) apresentavam neoplasias malignas, sendo que 15, 21, 46, 17 e 14 animais encontravam-se em estadiamento clínico I, II, III, IV e V respectivamente, e o carcinoma em tumor misto foi o padrão histológico mais frequente neste grupo (26%). Trinta e um animais tiveram diagnóstico de neoplasias benignas, sendo que 7 estavam no estádio I, 16 no estádio II e 8 no estádio III e o adenoma mamário foi o padrão histológico mais frequente em 15 animais (51,61%). Alterações hematológicas no período pré-operatório foram observadas em 44 (38,9%) e 12 (38,7%) animais portadores de neoplasias malignas e benignas, respectivamente, sendo que houve correlação positiva entre anemia e níveis mais elevados de MDA (P=0,0008), para os animais com tumores malignos. Em relação aos parâmetros bioquímicos séricos, as alterações mais frequentes nos animais com neoplasias malignas foram a elevação dos níveis de ALT em 12 animais (10,6%), de creatinina em 10 animais (8,84%) e de ureia em oito animais (7,07%) Cadelas portadoras de neoplasias benignas apresentaram menor ocorrência de alterações nesses parâmetros. No grupo controle, a média dos valores séricos de MDA foi 12,08±4,18, enquanto que no grupo pré-tratamento, a média de MDA foi de 24,80±5,74 para as cadelas com neoplasia benigna e 32,27±10,24 para as neoplasias malignas. Verificou-se aumento significativo do valor sérico de MDA em cadelas portadoras de neoplasias malignas em comparação com os animais hígidos ou com neoplasias benignas (P<0,001). Ainda, 30 dias após o tratamento observou-se uma diminuição significativa (P<0,001) no valor médio de MDA (27,37±7,86) nos animais com neoplasias malignas. Em conclusão, os resultados deste estudo evidenciam uma associação entre níveis séricos aumentados de MDA e presença de neoplasias mamárias em cadelas. Os resultados sugerem que este fator pode ser utilizado como biomarcador de estresse oxidativo em cães, com provável impacto no prognóstico dos tumores mamários, uma vez que níveis significativamente mais altos de MDA foram detectados especialmente nas cadelas portadoras de tumores malignos e apresentando anemia.


#10 - Accuracy of B-mode ultrasonography for detecting malignancy in canine cutaneous neoplasms: preliminary results

Abstract in English:

The aim of this study was to verify the applicability and accuracy of B-mode ultrasonography in detecting malignancy in dog cutaneous neoplasms. Forty-two neoplasms (12 benign and 30 malignant) of mesenchymal, round cells, epithelial and melanocytic origins from 24 dogs of different breeds and ages were included. The ultrasound evaluation was performed with a linear multi-frequency transducer (7.0 to 12MHz), with frequency dependent on the mass dimension. Ultrasonographic characteristics of echogenicity (hypo/hyperechogenic), echotexture (homogeneous/heterogeneous), regularity, invasiveness in adjacent tissues were classified. Dimensions were also measured to calculate the depth/width ratio. Neoplasms were classified as malignant or benign after cytological and/or histopathological analysis and the results were associated with ultrasound characteristics. There was a significant association (P<0.05) between malignancy and echogenicity, echotexture and invasiveness in adjacent tissues, so that 84.6% of hypoechogenic neoplasms, 76.9% of heterogeneous masses and 88.2% of invasive neoplasms were classified as malignant. However, for all these associations, moderate predictive values were obtained, which may be due to the small experimental number included in this study. Therefore, although it has been observed that hypoechogenic, heterogeneous and invasive neoplasms were more prone to malignancy, these findings should be used with caution until new studies are developed with a greater number and variety of cutaneous neoplasms in dogs.

Abstract in Portuguese:

O objetivo deste estudo foi verificar a aplicabilidade e acurácia da ultrassonografia modo-B na detecção de malignidade em neoplasmas cutâneos de cães. Foram incluídos 42 neoplasmas (12 benignos e 30 malignos) de origens mesenquimal, células redondas, epitelial e melanocítica provenientes de 24 cães de diferentes raças e idades. O exame ultrassonográfico foi realizado com transdutor linear multifrequencial (7.0 a 12MHz), com frequência dependente da dimensão da massa. Foram classificadas características ultrassonográficas de ecogenicidade (hipo/hiperecogênicos), ecotextura (homogêneos/heterogêneos), regularidade, invasividade em tecidos adjacentes. As dimensões foram mensuradas para cálculo da razão profundidade/largura. Os neoplasmas foram classificados como malignos ou benignos após análise cito e/ou histopatológica e os resultados foram associados com as características ultrassonográficas. Verificou-se associação significativa (P<0.05) entre malignidade e ecogenicidade, ecotextura e invasividade em tecidos adjacentes, de forma que 84.6% dos neoplasmas hipoecogênicos, 76.9% das massas heterogêneas e 88.2% dos neoplasmas invasivos foram classificados como malignos. Entretanto, para todas essas associações, foram obtidos valores preditivos moderados, que podem ser decorrentes do baixo número experimental incluso neste estudo. Sendo assim, embora tenha sido observado que os neoplasmas hipoecogênicos, heterogêneos e invasivos tiveram maior propensão à malignidade, esses achados devem ser utilizados com cautela até novos trabalhos sejam desenvolvidos com maior número e variedade de neoplasmas cutâneos de cães.


Colégio Brasileiro de Patologia Animal SciELO Brasil CAPES CNPQ UNB UFRRJ CFMV