Canine mammary neoplasms - evaluation of tumor microenvironment

Background: The tumor microenvironment is an important target of studies in different types of neoplasms. Understanding the role of general components such as immune, vascular and fibroblastic cells has the objective of contributing to prognosis and treatment. The aim of this study was to evaluate the relationship between mast cells and angiogenesis in benign and malignant mammary neoplasms by investigating the role of degranulation and microlocation of mast cells and neoformed vessels in canine mammary neoplasms. Materials, Methods & Results: Mammary glands (n = 122) from 50 female dogs submitted to mastectomy without chemotherapy were evaluated and categorized into 3 groups: control group (n = 46); malignant group (n = 57) and benign group (n = 19). Lymph nodes without changes (n = 59) and with metastases (n = 6) were also evaluated. To evaluate the MCD (mast cell density) and angiogenesis, Toluidine Blue (0.1%) and Gomori’s Trichrome techniques were performed and adapted from previous studies. Photomicrographs of 10 hotspot areas on a 40x objective lens of the mammary glands and lymph nodes were captured to assess MCD and angiogenesis. In the absence of these areas, random fields were captured. For the mammary glands of the malignant and benign groups, 20 fields were analyzed, as the analysis considered the microlocation (peritumoral and intratumoral). Counting was performed manually using ImageJ software version 1.42q by 2 observers. The statistical analysis were performed using SPSS software version 19.0. The most frequent histological type in the malignant group was carcinoma in mixed tumor (68.42%; 39/57) and in the benign group was benign mixed tumor (57.89%; 11/19). Female dogs without breed pattern were more frequently affected represented 70% of the animals and the mean age was 9 years and 8 months ± 3 years and 1 month...

Canine mammary neoplasms - evaluation of tumor microenvironment

Background: The tumor microenvironment is an important target of studies in different types of neoplasms. Understanding the role of general components such as immune, vascular and fibroblastic cells has the objective of contributing to prognosis and treatment. The aim of this study was to evaluate the relationship between mast cells and angiogenesis in benign and malignant mammary neoplasms by investigating the role of degranulation and microlocation of mast cells and neoformed vessels in canine mammary neoplasms. Materials, Methods & Results: Mammary glands (n = 122) from 50 female dogs submitted to mastectomy without chemotherapy were evaluated and categorized into 3 groups: control group (n = 46); malignant group (n = 57) and benign group (n = 19). Lymph nodes without changes (n = 59) and with metastases (n = 6) were also evaluated. To evaluate the MCD (mast cell density) and angiogenesis, Toluidine Blue (0.1%) and Gomoris Trichrome techniques were performed and adapted from previous studies. Photomicrographs of 10 hotspot areas on a 40x objective lens of the mammary glands and lymph nodes were captured to assess MCD and angiogenesis. In the absence of these areas, random fields were captured. For the mammary glands of the malignant and benign groups, 20 fields were analyzed, as the analysis considered the microlocation (peritumoral and intratumoral). Counting was performed manually using ImageJ software version 1.42q by 2 observers. The statistical analysis were performed using SPSS software version 19.0. The most frequent histological type in the malignant group was carcinoma in mixed tumor (68.42%; 39/57) and in the benign group was benign mixed tumor (57.89%; 11/19). Female dogs without breed pattern were more frequently affected represented 70% of the animals and the mean age was 9 years and 8 months ± 3 years and 1 month...(AU)

Analysis of systemic and cutaneous inflammatory immune response in canine atopic dermatitis

Background: Canine atopic dermatitis (CAD) is a chronic and inflammatory disease present in veterinary dermatologicalpractice. The inflammation in CAD is triggered by environmental allergens and skin microorganisms, which are responsiblefor the worsening of cutaneous lesions. This continuous activation of skin inflammatory process can induce the productionof free radicals that also contribute to cellular damage and ultimately leads to changes in blood parameters in dogs withCAD. Although there are reports of inflammatory parameters in CAD, there are a lack of studies correlating skin lesions,blood leukocytes and oxidative stress. Based on that, this study aimed to evaluate the integumentary and systemic inflammatory response in dogs with atopic dermatitis.Materials, Methods & Results: Dogs with confirmed diagnosis of canine atopic dermatitis (n = 10) were divided in twogroups according to CADESI-IV: AI, with CADESI between 0-10, AII, with CADESI between 10-34, and control group (n= 5). Blood-biochemical and histological analysis were performed to access systemic and cutaneous inflammatory response.AII group tended to higher neutrophil and eosinophil counts, as well as neutrophil/lymphocyte ratio (NLR) when comparedto AI. The albumin was lower in AII compared to AI and control (P < 0.05), while total bilirubin and malondialdehyde(MDA) did not differ between groups. NLR (r = 0.64 and P = 0.04) and MDA (r = 0.54 and P = 0.1) were positively correlated with CADESI, while albumin was negatively correlated with CADESI (r = -0.79 and P = 0.005). Histopathologicalanalysis revealed a larger number of neutrophils, macrophages and mast cells in AI and AII than in control group (P < 0.05).Discussion: In this study it was possible to evaluate the systemic and cutaneous leukocyte dynamics in CAD. Skin inflammation induces the production of chemotactic molecules contribute to neutrophil outflow from blood vessel toward the...

Analysis of systemic and cutaneous inflammatory immune response in canine atopic dermatitis

Background: Canine atopic dermatitis (CAD) is a chronic and inflammatory disease present in veterinary dermatologicalpractice. The inflammation in CAD is triggered by environmental allergens and skin microorganisms, which are responsiblefor the worsening of cutaneous lesions. This continuous activation of skin inflammatory process can induce the productionof free radicals that also contribute to cellular damage and ultimately leads to changes in blood parameters in dogs withCAD. Although there are reports of inflammatory parameters in CAD, there are a lack of studies correlating skin lesions,blood leukocytes and oxidative stress. Based on that, this study aimed to evaluate the integumentary and systemic inflammatory response in dogs with atopic dermatitis.Materials, Methods & Results: Dogs with confirmed diagnosis of canine atopic dermatitis (n = 10) were divided in twogroups according to CADESI-IV: AI, with CADESI between 0-10, AII, with CADESI between 10-34, and control group (n= 5). Blood-biochemical and histological analysis were performed to access systemic and cutaneous inflammatory response.AII group tended to higher neutrophil and eosinophil counts, as well as neutrophil/lymphocyte ratio (NLR) when comparedto AI. The albumin was lower in AII compared to AI and control (P < 0.05), while total bilirubin and malondialdehyde(MDA) did not differ between groups. NLR (r = 0.64 and P = 0.04) and MDA (r = 0.54 and P = 0.1) were positively correlated with CADESI, while albumin was negatively correlated with CADESI (r = -0.79 and P = 0.005). Histopathologicalanalysis revealed a larger number of neutrophils, macrophages and mast cells in AI and AII than in control group (P < 0.05).Discussion: In this study it was possible to evaluate the systemic and cutaneous leukocyte dynamics in CAD. Skin inflammation induces the production of chemotactic molecules contribute to neutrophil outflow from blood vessel toward the...(AU)

Mast cells in the pathophysiology of Duchenne muscular dystrophy in Golden Retriever dogs / O papel dos mastócitos na patogênese da distrofia muscular de Duchenne em cães Golden Retriever

The Golden Retriever muscular dystrophy (GRMD) is one of the best models of Duchenne muscular dystrophy (DMD), with similar genotypic and phenotypic manifestations. Progressive proliferation of connective tissue in the endomysium of the muscle fibers occurs in parallel with the clinical course of the disease in GRMD animals. Previous studies suggest a relationship between mast cells and the deposition of fibrous tissue due to the release of mediators that recruit fibroblasts. The aim of this study was to evaluate the presence of mast cells and their relationship with muscle injury and fibrosis in GRMD dogs of different ages. Samples of muscle groups from six GRMD and four control dogs, aged 2 to 8 months, were collected and analyzed. The samples were processed and stained with HE, toluidine blue, and Azan trichrome. Our results showed that there was a significant increase in infiltration of mast cells in all muscle groups of GRMD dogs compared to the control group. The average number of mast cells, as well as the deposition of fibrous tissue, decreased with age in GRMD dogs. In the control group, all muscle types showed a significant increase in the amount of collagenous tissue. This suggests increased mast cell degranulation occurred in younger GRMD dogs, resulting in increased interstitial space and fibrous tissue in muscle, which then gradually decreased over time as the dogs aged. However, further studies are needed to clarify the role of mast cells in the pathogenesis of fibrosis.(AU)

O cão Golden Retriever distrófico (Golden Retriever muscular dystrophy - GRMD) é um dos melhores modelos da distrofia muscular de Duchenne (DMD), com manifestações genotípicas e fenotípicas similares. A proliferação progressiva de tecido conjuntivo no endomísio das fibras musculares ocorre paralelamente ao curso clínico da doença em animais GRMD. Estudos anteriores sugerem uma relação entre os mastócitos e a deposição de tecido fibroso devido à liberação de mediadores que recrutam fibroblastos. O objetivo deste estudo foi avaliar a presença de mastócitos e sua relação com a lesão muscular e fibrose em cães GRMD de diferentes idades. Amostras de grupos musculares de seis GRMD e quatro controles, com idade entre 2 a 8 meses, foram coletadas e analisadas. As amostras foram processadas e coradas com HE, azul de toluidina e tricrômico de Azan. Nossos resultados mostraram que houve um aumento significativo na infiltração de mastócitos em todos os grupos musculares de cães GRMD em comparação com o grupo controle. O número médio de mastócitos, assim como a deposição de tecido fibroso, diminuiu com a idade em cães GRMD. No grupo controle, todos os tipos musculares mostraram um aumento significativo na quantidade de tecido colágeno. Isto sugere o aumento da degranulação de mastócitos em cães GRMD mais jovens, resultando em aumento do espaço intersticial e tecido fibroso no músculo, que então gradualmente diminuiu com o tempo à medida que os cães envelheceram. No entanto, mais estudos são necessários para esclarecer o papel dos mastócitos na patogênese da fibrose.(AU)

Mast cells in the pathophysiology of Duchenne muscular dystrophy in Golden Retriever dogs / O papel dos mastócitos na patogênese da distrofia muscular de Duchenne em cães Golden Retriever

The Golden Retriever muscular dystrophy (GRMD) is one of the best models of Duchenne muscular dystrophy (DMD), with similar genotypic and phenotypic manifestations. Progressive proliferation of connective tissue in the endomysium of the muscle fibers occurs in parallel with the clinical course of the disease in GRMD animals. Previous studies suggest a relationship between mast cells and the deposition of fibrous tissue due to the release of mediators that recruit fibroblasts. The aim of this study was to evaluate the presence of mast cells and their relationship with muscle injury and fibrosis in GRMD dogs of different ages. Samples of muscle groups from six GRMD and four control dogs, aged 2 to 8 months, were collected and analyzed. The samples were processed and stained with HE, toluidine blue, and Azan trichrome. Our results showed that there was a significant increase in infiltration of mast cells in all muscle groups of GRMD dogs compared to the control group. The average number of mast cells, as well as the deposition of fibrous tissue, decreased with age in GRMD dogs. In the control group, all muscle types showed a significant increase in the amount of collagenous tissue. This suggests increased mast cell degranulation occurred in younger GRMD dogs, resulting in increased interstitial space and fibrous tissue in muscle, which then gradually decreased over time as the dogs aged. However, further studies are needed to clarify the role of mast cells in the pathogenesis of fibrosis.(AU)

O cão Golden Retriever distrófico (Golden Retriever muscular dystrophy - GRMD) é um dos melhores modelos da distrofia muscular de Duchenne (DMD), com manifestações genotípicas e fenotípicas similares. A proliferação progressiva de tecido conjuntivo no endomísio das fibras musculares ocorre paralelamente ao curso clínico da doença em animais GRMD. Estudos anteriores sugerem uma relação entre os mastócitos e a deposição de tecido fibroso devido à liberação de mediadores que recrutam fibroblastos. O objetivo deste estudo foi avaliar a presença de mastócitos e sua relação com a lesão muscular e fibrose em cães GRMD de diferentes idades. Amostras de grupos musculares de seis GRMD e quatro controles, com idade entre 2 a 8 meses, foram coletadas e analisadas. As amostras foram processadas e coradas com HE, azul de toluidina e tricrômico de Azan. Nossos resultados mostraram que houve um aumento significativo na infiltração de mastócitos em todos os grupos musculares de cães GRMD em comparação com o grupo controle. O número médio de mastócitos, assim como a deposição de tecido fibroso, diminuiu com a idade em cães GRMD. No grupo controle, todos os tipos musculares mostraram um aumento significativo na quantidade de tecido colágeno. Isto sugere o aumento da degranulação de mastócitos em cães GRMD mais jovens, resultando em aumento do espaço intersticial e tecido fibroso no músculo, que então gradualmente diminuiu com o tempo à medida que os cães envelheceram. No entanto, mais estudos são necessários para esclarecer o papel dos mastócitos na patogênese da fibrose.(AU)

Prevention of rocuronium induced mast cell activation with prophylactic oleuropein rich diet in anesthetized rabbits

Purpose:The effect of a prophylactic oleuropein-rich diet before anesthesia accompanied by the widely-used steroid-based neuromuscular drug rocuronium on mast cell activation was investigated in the study.Methods:14 rabbits used in the study. The rabbits in the oleuropein group were given oleuropein-rich extract added to the animals water at doses of 20 mg/kg oleuropein for 15 days orally. After 15 days, all rabbits in the two groups were given general anesthesia with rocuronium of 1 mg/kg. After 1 day, animals were sacrificed and the liver tissue sections stained with H&E, toluidine blue and tryptase for immunohistochemical study.Results:There was no statistically significant difference between ALT, AST and albumin averages of the oleuropein and control groups (p> 0.05). The tryptase average of the control group was higher than the tryptase average of the oleuropein group and this difference was statistically significant (p=0.003). The T. blue average in the oleuropein group was higher than the control group. However, there was no statistically significant difference between groups (p=0.482).Conclusions:Rocuronium adverse effects, like hypersensitivity and anaphylaxis, may limit routine use of this substance. The use of oleuropein reduced the number of inflammatory cells and prevented degranulation.(AU)

Mast cell concentration and skin wound contraction in rats treated with Ximenia americana L

Purpose: To evaluate wound contraction and the concentration of mast cells in skin wounds treated with wild plum (Ximenia americana) essential oil-based ointment in rats. Methods: Sixty rats were submitted to two cutaneous wounds in the thoracic region, on the right and left antimeres. Thereon, they were divided into three groups: GX (wounds treated once a day with hydro alcoholic branch extract of Ximenia americana), GP (wounds that received vehicle), and GC (wounds without product application). Wounds were measured immediately after the injury as well as 4, 7, 14 and 21 days post-topical application of the extract. At these days, five rats from each group were euthanatized. Thereafter, samples were fixed in 10% formaldehyde and processed for paraffin embedding. Sections were stained with H.E, Masson's Trichrome and toluidine blue for morphological, morphometrical and histopathological analysis, under light microscopy. The degree of epithelial contraction was measured and mast cell concentrations were also evaluated with an image analyzer (Image Pro-plus®software) . Results: The extract treated group showed lower mast cell concentrations in the 4th day of lesion, as compared to GP (GX GP=GC, p=0.029), as well as with increased contraction at 7th and 14th days, respectively (7th and 14th days, GX > GP = GC; p 0.05) . Conclusion: Ointment containing 10% X. americana induces a decrease in mast cell concentration, at the beginning of the healing process, and promotes early skin wound contraction in rats.(AU)

Outcome of adjuvant chemotherapy with lomustine, vinblastine and chlorambucil on management of canine mast cell tumour of high to intermediate risk / Resultado da quimioterapia adjuvante com lomustina, vimblastina e clorambucil no manejo do mastocitoma canino de risco alto a intermediário

In spite of the many available protocols, the use of chemotherapy for the management of canine mast cell tumours (MCT) remains empirical, and there is lack of criteria for the choice of protocol and definition of patients who may benefit from treatment. The objective of this study was to evaluate the outcome of dogs with MCT after adjuvant chemotherapy according to the risk of recurrence or metastasis proposed on the literature. This prospective study included 89 followed up dogs with prognosis assesment including clinical, histological, immunohistochemical and genetic features of canine MCT. Patients were grouped according to risk of recurrence and metastasis and recommended treatment with lomustine followed by chlorambucil if considered at high-risk, or vinblastine followed by chlorambucil if a patient was at intermediate risk. Outcome was defined by disease-free interval (DFI) and overall survival (OS) estimated by Kaplan-Meier curve. Adjuvant lomustine was useful for control of canine MCT of high-risk of recurrence or metastasis, but only when sequentially associated to chlorambucil with a DFI of 686 days and not reached OS. There was no difference in outcome in the intermediate-risk group despite choosen treatment. Patients at intermediate-to-low risk may not require adjuvant treatments, even in the absence of free surgical margins.(AU)

Apesar dos inúmeros protocolos disponíveis, o uso da quimioterapia permanece empírico para o mastocitoma canino e faltam critérios para escolha do protocolo e da definição dos pacientes que poderiam se beneficiar do tratamento. O objetivo deste estudo foi avaliar o resultado de cães com mastocitoma após a quimioterapia adjuvante, de acordo com o risco de recorrência ou metástase proposto na literatura. Este estudo prospectivo incluiu 89 cães com acompanhamento clínico e avaliação prognóstica, incluindo características clínicas, histológicas, imuno-histoquímicas e genéticas dos mastocitomas. Os pacientes foram agrupados segundo o risco de recorrência ou metástase, sendo recomendado tratamento com lomustina seguida de clorambucila, se considerados sob alto risco, ou vimblastina seguida de clorambucila, se estivessem sob risco intermediário. O resultado final foi definido pelo intervalo livre de doença (ILD) e pela sobrevida global (SG), estimados pela curva de Kaplan-Meier. Na adjuvância, a lomustina foi útil no controle do mastocitoma canino de alto risco, mas apenas quando associada ao clorambucila, com um ILD de 686 dias, sem atingir a mediana para SG. Não houve diferença no grupo de risco intermediário, independentemente do tratamento escolhido. Pacientes de risco intermediário podem não necessitar de tratamentos adjuvantes, mesmo na ausência de margens cirúrgicas livres.(AU)

Outcome of adjuvant chemotherapy with lomustine, vinblastine and chlorambucil on management of canine mast cell tumour of high to intermediate risk

ABSTRACT In spite of the many available protocols, the use of chemotherapy for the management of canine mast cell tumours (MCT) remains empirical, and there is lack of criteria for the choice of protocol and definition of patients who may benefit from treatment. The objective of this study was to evaluate the outcome of dogs with MCT after adjuvant chemotherapy according to the risk of recurrence or metastasis proposed on the literature. This prospective study included 89 followed up dogs with prognosis assesment including clinical, histological, immunohistochemical and genetic features of canine MCT. Patients were grouped according to risk of recurrence and metastasis and recommended treatment with lomustine followed by chlorambucil if considered at high-risk, or vinblastine followed by chlorambucil if a patient was at intermediate risk. Outcome was defined by disease-free interval (DFI) and overall survival (OS) estimated by Kaplan-Meier curve. Adjuvant lomustine was useful for control of canine MCT of high-risk of recurrence or metastasis, but only when sequentially associated to chlorambucil with a DFI of 686 days and not reached OS. There was no difference in outcome in the intermediate-risk group despite choosen treatment. Patients at intermediate-to-low risk may not require adjuvant treatments, even in the absence of free surgical margins.

RESUMO Apesar dos inúmeros protocolos disponíveis, o uso da quimioterapia permanece empírico para o mastocitoma canino e faltam critérios para escolha do protocolo e da definição dos pacientes que poderiam se beneficiar do tratamento. O objetivo deste estudo foi avaliar o resultado de cães com mastocitoma após a quimioterapia adjuvante, de acordo com o risco de recorrência ou metástase proposto na literatura. Este estudo prospectivo incluiu 89 cães com acompanhamento clínico e avaliação prognóstica, incluindo características clínicas, histológicas, imuno-histoquímicas e genéticas dos mastocitomas. Os pacientes foram agrupados segundo o risco de recorrência ou metástase, sendo recomendado tratamento com lomustina seguida de clorambucila, se considerados sob alto risco, ou vimblastina seguida de clorambucila, se estivessem sob risco intermediário. O resultado final foi definido pelo intervalo livre de doença (ILD) e pela sobrevida global (SG), estimados pela curva de Kaplan-Meier. Na adjuvância, a lomustina foi útil no controle do mastocitoma canino de alto risco, mas apenas quando associada ao clorambucila, com um ILD de 686 dias, sem atingir a mediana para SG. Não houve diferença no grupo de risco intermediário, independentemente do tratamento escolhido. Pacientes de risco intermediário podem não necessitar de tratamentos adjuvantes, mesmo na ausência de margens cirúrgicas livres.

Outcome of adjuvant chemotherapy with lomustine, vinblastine and chlorambucil on management of canine mast cell tumour of high to intermediate risk / Resultado da quimioterapia adjuvante com lomustina, vimblastina e clorambucil no manejo do mastocitoma canino de risco alto a intermediário

In spite of the many available protocols, the use of chemotherapy for the management of canine mast cell tumours (MCT) remains empirical, and there is lack of criteria for the choice of protocol and definition of patients who may benefit from treatment. The objective of this study was to evaluate the outcome of dogs with MCT after adjuvant chemotherapy according to the risk of recurrence or metastasis proposed on the literature. This prospective study included 89 followed up dogs with prognosis assesment including clinical, histological, immunohistochemical and genetic features of canine MCT. Patients were grouped according to risk of recurrence and metastasis and recommended treatment with lomustine followed by chlorambucil if considered at high-risk, or vinblastine followed by chlorambucil if a patient was at intermediate risk. Outcome was defined by disease-free interval (DFI) and overall survival (OS) estimated by Kaplan-Meier curve. Adjuvant lomustine was useful for control of canine MCT of high-risk of recurrence or metastasis, but only when sequentially associated to chlorambucil with a DFI of 686 days and not reached OS. There was no difference in outcome in the intermediate-risk group despite choosen treatment. Patients at intermediate-to-low risk may not require adjuvant treatments, even in the absence of free surgical margins.(AU)

Apesar dos inúmeros protocolos disponíveis, o uso da quimioterapia permanece empírico para o mastocitoma canino e faltam critérios para escolha do protocolo e da definição dos pacientes que poderiam se beneficiar do tratamento. O objetivo deste estudo foi avaliar o resultado de cães com mastocitoma após a quimioterapia adjuvante, de acordo com o risco de recorrência ou metástase proposto na literatura. Este estudo prospectivo incluiu 89 cães com acompanhamento clínico e avaliação prognóstica, incluindo características clínicas, histológicas, imuno-histoquímicas e genéticas dos mastocitomas. Os pacientes foram agrupados segundo o risco de recorrência ou metástase, sendo recomendado tratamento com lomustina seguida de clorambucila, se considerados sob alto risco, ou vimblastina seguida de clorambucila, se estivessem sob risco intermediário. O resultado final foi definido pelo intervalo livre de doença (ILD) e pela sobrevida global (SG), estimados pela curva de Kaplan-Meier. Na adjuvância, a lomustina foi útil no controle do mastocitoma canino de alto risco, mas apenas quando associada ao clorambucila, com um ILD de 686 dias, sem atingir a mediana para SG. Não houve diferença no grupo de risco intermediário, independentemente do tratamento escolhido. Pacientes de risco intermediário podem não necessitar de tratamentos adjuvantes, mesmo na ausência de margens cirúrgicas livres.(AU)

Técnica adaptada para determinação do índice proliferativo AgNOR em amostras citológicas de mastocitoma canino

Mastocitomas são proliferações neoplásicas de mastócitos pouco comuns na maioria das espécies e frequentes em animais de estimação. A grande maioria ocorre na derme e tecido subcutâneo e a etiopatogenia é desconhecida. Sua aparência clínica varia amplamente e sempre deve ser considerado potencialmente maligno, podendo estar associado à manifestação de sinais clínicos causados pela liberação de aminas vasoativas que estão presentes nos grânulos dos mastócitos. Deve ser feita investigação de possíveis metástases e, sempre que possível, remoção cirúrgica para graduação histológica do tumor, que é o exame padrão-ouro na determinação prognóstica do mastocitoma. O exame citopatológico é a ferramenta diagnóstica inicial, de baixo custo, rápida e não invasivo para o diagnóstico do mastocitoma. Recentemente, sistemas de graduação citológica do mastocitoma vem sendo propostos, possibilitando a identificação precoce do grau do tumor, o que pode ser útil para planejar estratégias de tratamento e discutir o prognóstico com o proprietário do cão. Outros marcadores podem e devem ser empregados para identificar o índice proliferativo do tumor, como a contagem de regiões organizadoras nucleolares argirofílicas (AgNORs). Este trabalho busca gerar dados que auxiliem na caracterização da apresentação do paciente com mastocitoma em associação ao índice proliferativo AgNOR. Neste sentido, foram gerados dois manuscritos acerca da abordagem prática do paciente canino com mastocitoma. No primeiro manuscrito, foi padronizada uma técnica para determinar o índice proliferativo AgNOR coletadas citológicas, através da qual possibilitou-se impregnar lâminas previamente coradas com corantes de rotina, antecipando assim o índice proliferativo tumoral. No segundo manuscrito, foram selecionados 63 casos de cães com mastocitoma, os quais tiveram o índice AgNOR relacionado ao sexo, raça, local e grau citológico. Os achados demonstram que não há predisposição sexual nem racial para elevados índices AgNOR, mas em alguns locais anatômicos o desenvolvimento do mastocitoma possui maiores índices proliferativos. Também observou-se que altos índices AgNOR estão associados a mastocitomas de alto grau citológico, o que pode representar um pior prognóstico. Dessa forma, sugere-se avaliar o paciente com mastocitoma no pré-cirúrgico através do estadiamento clínico conjuntamente à análise citológica e índice AgNOR citológico para o adequado direcionamento das estratégias terapêuticas. A utilização do marcador proliferativo AgNOR é vantajosa pois é de execução rápida e fácil e fornece suporte para que a abordagem clínica tenha melhores resultados, permitindo definir a necessidade de procedimentos terapêuticos complementares além da remoção cirúrgica

Mast cell tumors are neoplastic proliferations of mast cells, uncommon in most species and frequent in pets. Majority of MCT occur in the dermis and subcutaneous tissue and the etiopathogenesis is unknown. Its clinical appearance varies a lot and must always be considered potentially malignant, and may be associated with the expression of clinical signs caused by the release of vasoactive amines that are present in mast cell granules. Metastases should be searched and, whenever possible, surgical removal for histological grading of the tumor, which is the gold standard exam in the prognostication of mast cell tumor. The cytopathological exam is the initial, inexpensive, fast, and non-invasive tool for diagnosing mast cell tumors. Recently, cytological grading systems for mast cell tumors have been proposed, enabling the early identification of the tumor grade, which can be useful to plan treatment strategies and discuss the prognosis with the dog's owner. Other markers should be used to identify the proliferative index of the tumor, such as the count of argyrophilic nucleolar organizer regions (AgNORs). This work aims to generate information to advise about the presentation of patients with mast cell tumors in association with the AgNOR proliferative index. Thus, two manuscripts were produced about the practical approach of the canine patient with mast cell tumor. In the first manuscript, a technique to determine the AgNOR proliferative index collected from cytology was standardized, through which it was possible to impregnate slides previously stained with routine dyes, thus anticipating the tumor proliferative index. In the second manuscript, 63 cases of dogs with mast cell tumors were selected, which had the AgNOR index related to sex, breed, location and cytological grade. The findings demonstrate that there is no sexual or racial predisposition to high AgNOR indices, but in some anatomical sites the development of mast cell tumors has higher proliferative indices. It was also observed that high AgNOR indices are associated with high cytological grade mast cell tumors, which may represent a worse prognosis. Thus, it is suggested to evaluate the patient with mast cell tumor in the pre-surgical period by clinical staging, cytological analysis and cytological AgNOR index for the proper targeting of therapeutic strategies. The use of the AgNOR proliferative marker is useful because it is quick and easy to perform and provides support for the clinical approach having better results, helping to define the need for complementary therapeutic procedures in addition to surgical removal.

CORRELAÇÃO ENTRE DIFERENTES GRADUAÇÕES DE MASTOCITOMA CANINO E NÚMERO DE EOSINÓFILOS, EXPRESSÃO DE INTERLEUCINA-5, RECEPTOR DE FATOR DE CRESCIMENTO ENDOTELIAL VASCULAR E PADRÕES DE KIT

A proliferação neoplásica de mastócitos, denominada mastocitoma, é a neoplasia cutânea mais comum em cães. O mastocitoma canino é altamente heterogêneo na apresentação clínica e no comportamento biológico, com um potencial variável de recorrência e metástase; assim, torna-se necessário identificar fatores prognósticos preditivos. É comum observar infiltração de eosinófilos na proximidade de mastócitos em tecidos inflamados alérgicos e em diversas doenças parasitárias bem como nos mastocitomas caninos. Mastócitos e eosinófilos participam de um complexo ciclo de autoperpetuação. Os eosinófilos produzem mediadores responsáveis pela diferenciação, ativação, proliferação e sobrevivência de mastócitos e estes quando ativados liberam mediadores, como IL-5, que favorecem o recrutamento e a ativação de eosinófilos. Apesar da grande casuística de mastocitoma canino, não existem relatos na literatura que correlacionem a sua graduação com número de eosinófilos e fatores que possam estar relacionados à sua quantidade no tecido tumoral. Foram utilizadas 48 amostras de mastocitoma de cães enviadas ao Laboratório de Histopatologia da Clínica Veterinária Escola da PUCPR. As lâminas obtidas das amostras foram coradas pelas técnicas de hematoxilina-eosina e May Grünwald-Giemsa, nas quais foram realizadas as graduações histológicas e contagem de eosinófilos. Para a avaliação imuno-histoquímica as amostras foram incubadas com os anticorpos anti IL-5, VEGFr e c-KIT. A porcentagem de área imunomarcada com IL-5 e VEGFr foi determinada, e as amostras incubadas com c-KIT foram classificadas de acordo com o padrão de imunomarcação. Das 48 amostras graduadas segundo Patnaik, 24 (50%) apresentaram grau I, 23 (47,9%) grau II e apenas uma amostra (2,1%) foi classificada como grau III, enquanto de acordo com Kiupel, 11 amostras (22,9%) foram classificadas como de alto grau, e 37 (77,15%) de baixo grau. Foi realizada uma comparação da média da contagem de eosinófilos das amostras entre as graduações histológicas e os diferentes padrões de KIT, a qual mostrou uma diferença significativa entre os padrões I e III de KIT, tendo o padrão III apresentado uma maior média de eosinófilos. Não foi observada correlação das graduações histológicas com IL-5 e VEGFr, por outro lado, demonstrou-se uma correlação positiva entre os padrões de c-KIT e as graduações de Patnaik e Kiupel (p= 0,0006 e p= 0,0267, respectivamente). Não foi observada correlação significativa da contagem de eosinófilos com nenhum anticorpo avaliado. Mais estudos devem ser feitos afim de comparar estes resultados com a evolução clínica dos animais, procurando correlacionar estes dados com prognóstico clínico.

Mast cell tumor is a neoplastic proliferation of mast cells and is the most common skin cancer in dogs. Canine mast cell tumor is highly heterogeneous in clinical presentation and biological behavior with a variable potential for recurrence and metastasis, so it is necessary to identify predictive prognostic factors. It is notable that the infiltration of eosinophils is detected close to mast cells in inflamed allergic tissues and also in several parasitic diseases as well as mast cell tumors. Mast cells and eosinophils participate in a complex cycle of self-perpetuation. Eosinophils produce mediators responsible for the differentiation, activation, proliferation and survival of mast cells, these when activated release mediators, such as IL-5, that favor the recruitment and activation of eosinophils. Despite the large number of canine mast cell tumors, there are no reports in the literature that correlate their grade with number of eosinophils and factors that may be related to their quantity in the tumor tissue. Forty-eight samples of canine mast cell tumors were sent to the Histopathology Laboratory of the Clínica Veterinária Escola at PUCPR, Curitiba. The slides obtained from the samples were stained using the hematoxylin-eosin and May Grünwald-Giemsa techniques, in which histological grading and eosinophil count were performed. For immunohistochemical evaluation, samples were incubated with antibodies IL-5, VEGFr and c-KIT. The immunostained percentage area with IL-5 and VEGFr was determined, and samples incubated with c-KIT were classified according to the immunostaining pattern. Of the 48 graduated samples, 24 (50%) presented grade I, 23 (47.9%) grade II and only one sample (2.1%) was classified as grade III according to Patnaiks mast cell tumor paterns. On the other hand, 11 samples (22.9%) were classified as high grade, and 37 (77.15%) as low grade according to Kiupels mast cell tumor classification. A comparison of the mean of eosinophil count in the samples between the histological grades and the different KIT patterns was also conducted, which showed a significant difference between KIT patterns I and III, in which pattern III had a higher mean of eosinophils. No correlation of histological grades with IL-5 and VEGFr was observed, c-KIT patterns demonstrated a positive correlation between the and the Patnaik and Kiupel grades (p = 0.0006 and p = 0.0267, respectively). There was no significant correlation between eosinophil count with any antibody evaluated. Further studies should be done to compare these results with the clinical evolution of the animals, seeking to correlate these data with clinical prognosis.

Aspectos patológicos de mastocitomas cutâneos com metástases em cães

O mastocitoma é uma das neoplasias cutâneas mais frequentemente diagnosticadas em cães e possui comportamento biológico amplo, variando de tumores bem diferenciados a tumores com comportamento maligno e doença metastática disseminada. As principais localizações anatômicas das metástases em cães são pouco estudadas, principalmente devido à falta de realização de necropsia nesses casos. O objetivo deste estudo foi avaliar os principais sítios metastáticos de mastocitomas cutâneos caninos e descrever os aspectos macroscópicos e histológicos das metástases. Foi conduzido um estudo retrospectivo nos arquivos de necropsia do Laboratório de Patologia Veterinária da Universidade Federal do Rio Grande do Sul de Janeiro de 2008 a Março de 2020 em busca de casos de mastocitomas cutâneos com metástases em cães. No período de 12 anos foram detectados 49 casos, todos classificados como mastocitomas cutâneos de alto grau. Os principais sítios metastáticos relatados foram os linfonodos (47/49; 95,9%), seguidos do baço (33/49;67,3%), fígado (29/49; 59,2%), medula óssea (20/49; 40,8%), rim (16/49; 32,7%) e coração (14/49; 28,6%). Outras localizações incomuns incluíram os pulmões (9/49; 18,4%), glândulas adrenais (4/49; 8,2%), músculo esquelético (4/49; 8,2%), osso (3/49; 6,1%), bexiga (2/49; 4.1%), próstata (2/49; 4.1%), esôfago (2/49; 4.1%), intestino delgado (2/49; 4.1%) e palato mole (1/49; 2%). Macroscopicamente, os linfonodos afetados apresentavam, em todos os casos, leve a acentuado aumento de volume, frequentemente com perda de distinção corticomedular. O padrão de metástase esplênica foi predominantemente caracterizado por esplenomegalia (28/33; 84,8%), por vezes associado a nódulos (13/33; 39,4%) e áreas puntiformes brancas (4/33; 12,1%). Hepatomegalia foi a principal apresentação macroscópica de metástase hepática (28/29; 96,5%), associada a áreas puntiformes brancas (9/29; 31%) e nódulos (2/29; 6,9%). Metástases renais eram caracterizadas por nódulos unilaterais ou bilaterais (9/16; 56,3%), áreas puntiformes brancas (3/16; 18,8%) ou palidez difusa do parênquima (1/16; 6,3%). O coração exibia nódulos na superfície epicárdica (6/14; 42,9%), palidez difusa (2/14; 14,3%) ou múltiplas áreas brancas no miocárdio (1/14; 7,1%). Nódulos metastáticos pulmonares foram observados em dois casos, enquanto nos demais sete cães as lesões eram apenas microscópicas e envolviam os vasos dos septos alveolares. Histologicamente, os linfonodos apresentavam obliteração do parênquima por mastócitos neoplásicos, os quais também estavam presentes nos seios medulares. No baço, as células neoplásicas estavam dispersas no parênquima (16/33; 48,5%), formando nódulos (10/33; 30,3%) ou difusamente distribuídas (9/33; 27,3%). No fígado, os mastócitos estavam principalmente nos sinusoides (24/29; 82,8%), formavam nódulos (10/29; 34,5%) e ocupavam espaços periportais (5/29; 17,2%). Nos rins e no coração, metástases intersticiais e nodulares foram observadas. Todas os mastocitomas apresentaram marcação imuno-histoquímica positiva para proteína KIT, com padrão de marcação KIT III em 29 casos (59,2%) e KIT II em 20 casos (40,8%).

Mast cell tumor (MCT) is one of the most common cutaneous neoplasms of dogs, and it has a variable biological behavior, ranging from well differentiated to more aggressive tumours with metastatic disease. Nonetheless, the main metastatic sites of MCT are poorly described because of the lack of necropsy in cases with MCT-related disease and death. This study aimed to evaluate the metastatic sites of canine MCT and describe the macroscopic and histologic aspects of the metastases. A retrospective study was performed using the necropsy database of the pathology laboratory of the Universidade Federal do Rio Grande do Sul between January 2008 and March 2020 in search for cases of metastatic cutaneous MCTs. In the 12-year period, 49 cases were selected, and all tumours were classified as high-grade MCTs. The main metastatic sites were the lymph nodes (47/49; 95.9%), followed by spleen (33/49; 67.3%), liver (29/49; 59.2%), bone marrow (20/49; 40.8%), kidneys (16/49; 32.7%) and heart (14/49; 28.6%). Other sites included the lungs (9/49; 18.4%), adrenal glands (4/49; 8.2%), skeletal muscle (4/49; 8.2%), bone (3/49; 6.1%), urinary bladder (2/49; 4.1%), prostate gland (2/49; 4.1%), esophagus (2/49; 4.1%;), small intestine (2/49; 4.1%) and soft palate (1/49; 2%). Grossly, there was mild to severe lymphadenomegaly in all cases, which was frequently accompanied by loss of the nodal corticomedullary differentiation. Splenic metastases were mainly characterized by splenomegaly (28/33; 84.8%), occasionally associated with nodules (13/33; 39.4%) and white pinpoint areas (4/33; 12.1%). Hepatomegaly was the most common gross feature of hepatic metastasis (28/29; 96.5%) and was associated with white pinpoint foci (9/29; 31%) and nodular areas (2/29; 6.9%). Renal metastases were characterized by unilateral or bilateral nodules (9/16; 56.3%), white pinpoint areas (3/16; 18.8%) or pale discoloration of the parenchyma (1/16; 6.3%). The heart had nodules in the epicardial surface (6/14; 42.9%), pale myocardium (2/14; 14.3%) or multifocal white areas in the myocardium (1/15; 7.1%). The lungs had metastatic nodules in 2 dogs, while in the remaining cases there were only histologic lesions with neoplastic mast cells in the blood vessels of alveolar septa. Histologically, the lymph nodes were obliterated by neoplastic mast cells, which were also in the medullary sinus. In the spleen, neoplastic mast cells were multifocally scattered (16/33; 48.5%), arranged in nodules (10/33; 30.3%) or diffusely distributed (9/33; 27.3%). In the liver, neoplastic cells were mainly in the sinusoids (24/29; 82.8%), but also formed nodules (10/29; 34.5%) and were arranged in a periportal pattern (5/29; 17.2%). In the kidneys and heart, interstitial and nodular metastases were observed. All neoplasms had positive immunolabeling for KIT protein, with KIT III staining pattern in 29 cases (59.2%) and KIT II staining pattern in 20 cases (40.8%).

Mast cell concentration and skin wound contraction in rats treated with Brazilian pepper essential oil (Schinus terebinthifolius Raddi)

PURPOSE: To evaluate wound contraction and the concentration of mast cells in skin wounds treated with 5% BPT essential oil-based ointment in rats.METHODS:Twenty rats, male, of adult age, were submitted to skin surgery on the right (RA) and left antimeres (LA) of the thoracic region. They were divided into two groups: control (RA - wounds receiving daily topical application of vaseline and lanolin) and treated (LA - wounds treated daily with the topical ointment). The skin region with wounds were collected at days 4, 7, 14 and 21 after surgery. Those were fixed in 10% formaldehyde and later processed for paraffin embedding. Sections were obtained and stained by H.E for histopathology analysis. The degree of epithelial contraction was measured and mast cell concentration were also evaluated.RESULTS:The treated group showed higher mast cell concentrations (p 0.05) associated with increased contraction at day 7 and 14 respectively.CONCLUSION: Ointment containing 5% Brazilian pepper tree oil increases mast cell concentration and promotes skin wound contraction in rats.(AU)

Aspectos citomorfológicos e frequência dos subtipos do tumor venéreo transmissível canino no município de Campo Grande, Mato Grosso do Sul, Brasil / Cytomorphological aspects and frequency of canine transmissible venereal tumor subtypes in the municipality of Campo Grande, Mato Grosso do Sul, Brazil

O tumor venéreo transmissível (TVT) é uma neoplasia indiferenciada de células redondas queacomete principalmente cães errantes, cuja atividade sexual não é acompanhada. O diagnóstico é realizadobaseando-se nos sinais clínicos e achados citológicos típicos das células esfoliadas. Entretanto, mudanças nascaracterísticas citomorfológicas têm sido observadas, permitindo-se a subdivisão nas classes linfocitóide,plasmocitóide e misto. Autores relataram diferenças na prevalência dos subtipos de TVT de acordo com asregiões brasileiras, porém esse tipo de informação é desconhecida na região Centro-Oeste. O conhecimentodessas informações torna-se imprescindível para o auxílio no diagnóstico e estabelecimento do tratamento eprognóstico apropriados nos animais de cada município e região. O trabalho teve como objetivo caracterizarcitologicamente os casos de TVT canino, diagnosticados em animais atendidos em um hospital escola domunicípio de Campo Grande, Mato Grosso do Sul, Brasil. A partir do diagnóstico de TVT em 70 animais, 88nódulos neoplásicos foram caracterizados por meio da citopatologia. A subclasse plasmocitóide representou81,8% dos casos. A extensa lista de critérios de malignidade, tanto nucleares quanto citoplasmáticos,caracterizaram como malignas todas as amostras estudadas. A presença de mastócitos (32,7%) destacou-se noinfiltrado inflamatório dos nódulos. O padrão observado assemelhou-se aos de outras regiões brasileiras,contudo, as circunstâncias para a frequente presença de mastócitos merecem maiores investigações

The transmissible venereal tumor (TVT) is an undifferentiated round cell tumor that mainlyaffects stray dogs, whose sexual activity is not monitored. The diagnosis is made based on clinical signs andtypical cytological findings of exfoliated cells. However, changes in cytomorphologic characteristics have beenobserved, allowing the subdivision in lynphocytoid, plasmacytoid and mixed classes. Authors reporteddifferences in the prevalence of TVT subtypes according to the Brazilian regions, however such information isunknown in the region center-west. The knowledge of this information becomes indispensable to aid in thediagnosis and establishment of appropriate treatment and prognosis in animals of each municipality and region.The goal of this paper was to characterize cytologically canine TVT cases, diagnosed in animals of CampoGrande, Mato Grosso do Sul, Brazil. From the diagnosis of TVT in 70 animals, 88 neoplastic nodules werecharacterized by cytopathology. The plasmacytoid subclass represented 81.8% of cases. The extensive list ofmalignancy criteria, both nuclear as cytoplasmic, characterized as malignant all samples. The presence of mastcells (32.7%) stood out in the inflammatory infiltrate of the nodules. The pattern observed was similar to otherbrazilian regions, however, circumstances for frequent presence of mast cells deserves further investigations

Aspectos citomorfológicos e frequência dos subtipos do tumor venéreo transmissível canino no município de Campo Grande, Mato Grosso do Sul, Brasil / Cytomorphological aspects and frequency of canine transmissible venereal tumor subtypes in the municipality of Campo Grande, Mato Grosso do Sul, Brazil

O tumor venéreo transmissível (TVT) é uma neoplasia indiferenciada de células redondas queacomete principalmente cães errantes, cuja atividade sexual não é acompanhada. O diagnóstico é realizadobaseando-se nos sinais clínicos e achados citológicos típicos das células esfoliadas. Entretanto, mudanças nascaracterísticas citomorfológicas têm sido observadas, permitindo-se a subdivisão nas classes linfocitóide,plasmocitóide e misto. Autores relataram diferenças na prevalência dos subtipos de TVT de acordo com asregiões brasileiras, porém esse tipo de informação é desconhecida na região Centro-Oeste. O conhecimentodessas informações torna-se imprescindível para o auxílio no diagnóstico e estabelecimento do tratamento eprognóstico apropriados nos animais de cada município e região. O trabalho teve como objetivo caracterizarcitologicamente os casos de TVT canino, diagnosticados em animais atendidos em um hospital escola domunicípio de Campo Grande, Mato Grosso do Sul, Brasil. A partir do diagnóstico de TVT em 70 animais, 88nódulos neoplásicos foram caracterizados por meio da citopatologia. A subclasse plasmocitóide representou81,8% dos casos. A extensa lista de critérios de malignidade, tanto nucleares quanto citoplasmáticos,caracterizaram como malignas todas as amostras estudadas. A presença de mastócitos (32,7%) destacou-se noinfiltrado inflamatório dos nódulos. O padrão observado assemelhou-se aos de outras regiões brasileiras,contudo, as circunstâncias para a frequente presença de mastócitos merecem maiores investigações(AU)

The transmissible venereal tumor (TVT) is an undifferentiated round cell tumor that mainlyaffects stray dogs, whose sexual activity is not monitored. The diagnosis is made based on clinical signs andtypical cytological findings of exfoliated cells. However, changes in cytomorphologic characteristics have beenobserved, allowing the subdivision in lynphocytoid, plasmacytoid and mixed classes. Authors reporteddifferences in the prevalence of TVT subtypes according to the Brazilian regions, however such information isunknown in the region center-west. The knowledge of this information becomes indispensable to aid in thediagnosis and establishment of appropriate treatment and prognosis in animals of each municipality and region.The goal of this paper was to characterize cytologically canine TVT cases, diagnosed in animals of CampoGrande, Mato Grosso do Sul, Brazil. From the diagnosis of TVT in 70 animals, 88 neoplastic nodules werecharacterized by cytopathology. The plasmacytoid subclass represented 81.8% of cases. The extensive list ofmalignancy criteria, both nuclear as cytoplasmic, characterized as malignant all samples. The presence of mastcells (32.7%) stood out in the inflammatory infiltrate of the nodules. The pattern observed was similar to otherbrazilian regions, however, circumstances for frequent presence of mast cells deserves further investigations(AU)

Grau de malignidade do mastocitoma cutâneo canino quanto a localização segundo as classificações de Patnaik et al. (1984) e Kiupel et al. (2011) / Degree of malignancy of the canine cutaneous mast cell tumor as forlocation according to the classifications of Patnaik et al. (1984) and Kiupel et al. (2011)

Objetivou-se com o presente trabalho coletar dados epidemiológicos relacionados com o mastocitoma canino, além de verificar se há relação entre sua malignidade e localização e, por fim, comparar os métodos de classificação histopatológica segundo Patnaik et al. (1984) e segundo Kiupel et al. (2011). Informações foram coletadas da ficha clínica de 55 cães e 60 fragmentos de pele com mastocitomas foram avaliados histologicamente. Verificou-se que a ocorrência de mastocitoma cutâneo não é influenciada pelo sexo e raça, porém cães sem raça definida e boxers são mais acometidos. Não há uma faixa etária susceptível bem definida, sendo o mastocitoma mais frequente em cães de 8 a 9 anos de idade. A região mais acometida foi a inguinal (50%) e a cabeça a região que apresentou mastocitomas com maior malignidade. Utilizando a classificação de Patnaik et al. (1984) houve diferença significativa entre as classificações histopatológicas de mastocitoma avaliadas por diferentes patologistas, o que não ocorreu utilizando a classificação de Kiupel et al. (2011). Pode-se dizer então que a classificação de Kiupel et al. (2011) gera menor divergência nos diagnósticos, demonstrando-se um método simples e eficaz para a avaliação histopatológica de mastocitoma.(AU)

The aim of the present study is to collect epidemiological data related to the canine mastocytoma, to check if there is relationbetween malignancy and its location and, finally, to compare the methods of histopathological classification according to Patnaiket al. (1984) and Kiupel et al. (2011). Informations were collected from the clinical record of 55 dogs and 60 fragments of skinwith a diagnosis of mast cell tumor were evaluated histologically. It was found that the occurrence of cutaneous mast cell tumorsis not influenced by gender and race, but dogs without defined breed and boxers are most affected. There is not a well-definedsusceptible age, but the most mast cell tumors in dogs often 8 to 9 years old. The highest affected region was inguinal (50%) andhead proved a region with higher malignancy. Using the classification Patnaik et al. (1984) there was a significant difference betweenthe histopathological ratings mastocytoma evaluated by different pathologists, which did not occur using the classification Kiupel etal. (2011). It can be said then that the classification Kiupel et al. (2011) generates less divergence in the diagnosis, demonstratinga simple and effective method for histopathological evaluation of mastocytoma.(AU)

Grau de malignidade do mastocitoma cutâneo canino quanto a localização segundo as classificações de Patnaik et al. (1984) e Kiupel et al. (2011) / Degree of malignancy of the canine cutaneous mast cell tumor as forlocation according to the classifications of Patnaik et al. (1984) and Kiupel et al. (2011)

Objetivou-se com o presente trabalho coletar dados epidemiológicos relacionados com o mastocitoma canino, além de verificar se há relação entre sua malignidade e localização e, por fim, comparar os métodos de classificação histopatológica segundo Patnaik et al. (1984) e segundo Kiupel et al. (2011). Informações foram coletadas da ficha clínica de 55 cães e 60 fragmentos de pele com mastocitomas foram avaliados histologicamente. Verificou-se que a ocorrência de mastocitoma cutâneo não é influenciada pelo sexo e raça, porém cães sem raça definida e boxers são mais acometidos. Não há uma faixa etária susceptível bem definida, sendo o mastocitoma mais frequente em cães de 8 a 9 anos de idade. A região mais acometida foi a inguinal (50%) e a cabeça a região que apresentou mastocitomas com maior malignidade. Utilizando a classificação de Patnaik et al. (1984) houve diferença significativa entre as classificações histopatológicas de mastocitoma avaliadas por diferentes patologistas, o que não ocorreu utilizando a classificação de Kiupel et al. (2011). Pode-se dizer então que a classificação de Kiupel et al. (2011) gera menor divergência nos diagnósticos, demonstrando-se um método simples e eficaz para a avaliação histopatológica de mastocitoma.

The aim of the present study is to collect epidemiological data related to the canine mastocytoma, to check if there is relationbetween malignancy and its location and, finally, to compare the methods of histopathological classification according to Patnaiket al. (1984) and Kiupel et al. (2011). Informations were collected from the clinical record of 55 dogs and 60 fragments of skinwith a diagnosis of mast cell tumor were evaluated histologically. It was found that the occurrence of cutaneous mast cell tumorsis not influenced by gender and race, but dogs without defined breed and boxers are most affected. There is not a well-definedsusceptible age, but the most mast cell tumors in dogs often 8 to 9 years old. The highest affected region was inguinal (50%) andhead proved a region with higher malignancy. Using the classification Patnaik et al. (1984) there was a significant difference betweenthe histopathological ratings mastocytoma evaluated by different pathologists, which did not occur using the classification Kiupel etal. (2011). It can be said then that the classification Kiupel et al. (2011) generates less divergence in the diagnosis, demonstratinga simple and effective method for histopathological evaluation of mastocytoma.

Mast cells and angiogenesis in canine mammary tumor / Mastócitos e angiogênese nos tumores mamários caninos

The correlation between microvessel density and mast cells density in canine mammary tumors was studied. Sixty-five samples of canine mammary tumors, being 24 benign and 41 malignant, were analyzed. The routine Toluidine Blue staining method was used to assess the mast cells. To evaluate angiogenesis, the immunohistochemical expression of CD31 was assessed. There was no significant difference in either mast cells (P=0.44) or microvessel density (P=0.77) between malignant and benign tumors. A positive correlation was observed between microvessel density and mast cells (r=0.39; P=0.011) in malignant tumors. These results suggest that mast cells may play a role in canine mammary malignant tumors development, promoting angiogenesis, similar to some tumors described in the human species.(AU)

Estimou-se a correlação entre a densidade de microvasos e a densidade de mastócitos em tumores mamários caninos. Sessenta e cinco amostras de tumores mamários caninos - 24 benignos e 41 malignos - foram analisadas, pela técnica rotineira de coloração com Azul de Toluidina para avaliação da densidade de mastócitos. Para a avaliação da angiogênese, foi utilizada a técnica de imunoistoquímica para expressão de CD31. Não foram observadas diferenças significativas de mastócitos (P=0.44) ou densidade microvascular (P=0.77) entre tumores malignos e benignos. A correlação entre densidade microvascular e densidade de mastócitos foi positiva (r=0,39; P=0,011) em tumores malignos. Estes resultados sugerem que os mastócitos podem exercer um importante papel no desenvolvimento de tumores mamários malignos caninos mediante promoção da angiogênese, similarmente a alguns tumores descritos na espécie humana.(AU)