Mutations of the c-KIT gene in canine mast cell tumors and respective nodal metastases classified according to mast cell infiltration / Mutações no gene c-KIT em mastocitomas caninos e respectivas metástases nodais classificados segundo a infiltração de mastócitos

The molecular background of canine mast cell tumors (MCT) has been extensively investigated; however, the dynamic molecular changes that occur during carcinogenesis and metastasis are not fully understood. This study aimed to evaluate the incidence of mutations in the c-KIT proto-oncogene in canine MCTs and relative draining regional lymph nodes. Suspected or confirmed lymph node metastasis was classified accordingly to the HN Weishaar classification. The study included 34 dogs diagnosed with MCT; 19 patients were enrolled prospectively. These dogs had the primary MCT and regional lymph node resected and analyzed simultaneously. The second group was evaluated retrospectively and included fifteen patients resectioning the primary MCT without evaluation of regional lymph node. Analyzes of c-KIT mutation were performed for all primary MCTs and, in the first group, compared between primary MCT and HN-classified metastasis. Internal tandem duplications (ITD) in exon 11 of the c-KIT gene were detected in 20% of patients. Ten of the nineteen patients (52%) in the first group presented mast cell infiltration in the regional lymph node, and ITD in exon 11 of the c-KIT gene was detected in five and two dogs from Groups 1 and 2, respectively. ITD c-KIT mutations are common in canine MCT and may be found in the draining lymph node metastases/mast cell infiltrates in the absence of mutation of the primary tumor. Evaluation of c-KIT mutation in the primary tumor and metastases may be informative for defining both prognosis and therapeutic options in MCT cases.

O perfil molecular do mastocitoma (MCT) tem sido bastante investigado, no entanto as dinâmicas moleculares que ocorrem durante a carcinogênese e metástase desta neoplasia não estão bem esclarecidas. O objetivo desse estudo foi avaliar a incidência de mutações no proto-oncogene c-KIT em MCTs caninos e respectivos linfonodos regionais. Os casos suspeitos ou confirmados de metástase para os linfonodos, foram classificados de acordo com a classificação HN de Weishaar. O estudo incluiu 34 cães diagnosticados com MCT e, desses, 19 pacientes foram avaliados de maneira prospectiva, em que o tumor primário e o linfonodo regional foram ressecados e analisados simultaneamente. O segundo grupo foi avaliado retrospectivamente e incluiu quinze pacientes que tiveram ressecção do MCT primário sem avaliação de linfonodo regional. A análise da mutação c-KIT foi realizada para todos os MCTs primários e, no primeiro grupo, comparados entre MCT primário e metástase classificada pelo sistema HN. Duplicações internas em tandem (DIT), no exon 11 do gene c-KIT, foram detectadas em um total de 20% dos pacientes. Dez dos dezenove pacientes (52%) do primeiro grupo apresentavam infiltração de mastócitos no linfonodo regional, e DIT no exon 11 do gene c-KIT foram identificadas em cinco e dois cães dos Grupos 1 e 2, respectivamente. Mutações do tipo DIT no gene c-KIT são comuns no MCT canino e podem estar presentes nas metástases/infiltrados de mastócitos na ausência de mutação do tumor primário. A avaliação da mutação no gene c-KIT no tumor primário e metástases pode ser informativa para definir tanto o prognóstico quanto as opções terapêuticas em casos de MCT.

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)

Abordagem diagnóstica de mastocitoma cutâneo metastático em canino / Diagnostic approach of metastatic cutaneous mastocytoma in dog

O mastocitoma é uma das neoplasias cutâneas mais comuns que acometem cães. O diagnóstico da doença é baseado em aspectos clínicos e laboratoriais, sendo a citologia e a histopatologia os métodos de eleição. Diante disso, o objetivo deste estudo é relatar a importância da ampla abordagem diagnóstica de mastocitoma cutâneo metastático em uma fêmea canina castrada, atendida no Hospital Veterinário da Universidade Estadual do Ceará, com uma neoformação em membro compatível com mastocitoma. O estadiamento da paciente foi feito através de exames laboratoriais de hemograma completo, e citologia aspirativa de linfonodo regional e medula óssea, que evidenciaram a presença de focos de metástase; bem como do exame de ultrassom abdominal, que evidenciou alterações no parênquima hepático e linfoadenomegalia ilíaco medial direita. Diante das suspeitas, optou-se pela eutanásia da paciente, cujo corpo foi enviado para os exames de necropsia e histopatologia, os quais confirmaram o diagnóstico de mastocitoma cutâneo de alto grau, com metástase em fígado, pulmão, medula e linfonodos. Desta forma pode-se concluir que o mastocitoma cutâneo metastático é uma neoplasia de diagnóstico multifatorial, em que a realização de exames hematológicos associados às análises citológicas, histopatológicas e de imagem são indispensáveis para estabelecer o diagnóstico definitivo para que seja determinada uma melhor conduta terapêutica e prognóstico de pacientes caninos.

Mast cell tumors are one of the most common skin neoplasms that affect dogs. The diagnosis is based on clinical and laboratory aspects, with cytology and histopathology being the preferred methods. Therefore, this study aims to report the importance of the broad diagnostic approach of metastatic cutaneous mastocytoma in a castrated a female dog attended at the Veterinary Hospital of the State University of Ceará, with a neoformation in a member compatible with mast cell tumor. The patient's staging was performed through laboratory tests of complete blood count, aspiration cytology of regional lymph nodes and bone marrow, which showed the presence of focus of metastasis, as well as the abdominal ultrasound examination, which showed changes in the liver parenchymas and right medial iliac lymphadenopathy. Given the suspicions, the patient was euthanized and the body was sent for necropsy and histopathological examination, which confirmed the diagnosis of high-grade cutaneous mast cell tumor, with metastasis in the liver, lung, bone marrow, and lymph nodes. Thus, it can be is concluded that mast cell tumor is a neoplasm of multifactorial diagnosis, where hematological tests associated with cytology, histopathological, and imaging analyses are essential to establish the definitive diagnosis to determine a better therapeutic behavior and prognosis of canine patients.

Mastocitoma cutâneo em uma cadela / Cutaneous mast cell tumor in a bitch

Background: The diagnostic of neoplasia in dogs has risen significantly in the last years and this fact is mostly attributed to the longer life expectancy of these animals, which contributes to a greater chance of exposure to carcinogenic agents. In between the diverse tumors that could compromise skin, the mastocytoma is the third most commonly diagnosed neoplasia. It is characterized by being a form of neoplasia with round cells, these being the mast cells. The objective of the present study consisted in relating a case of cutaneous mastocytoma in a 7-year-old bitch mixed-breed treated at the Veterinary Medical Teaching Hospital of the University of Uberaba (UNIUBE) - Uberaba, MG, Brazil. Case: The bitch initially presented a localized nodule external to the right ear pinna with cytology test suggesting a mastocytoma. The nodule was surgically removed and, posteriorly, an histopatholgy was not requested. After 5 months since the emergence of the nodule and a month after its surgical resection, the tutor noticed the presence of a new growth in the ipsilateral cervical region to the previous nodule. At this moment, the responsible veterinarian decided to refer the animal to an oncologist. During the appointment with the oncologist, alterations such as hyporexia and anemia were related, and the presence of a nodule in the right cervical region measuring 4.5 to 4 cm of diameter was verified. Material for cytologic evaluation of the neoplasia was collected and again the result suggested a mastocytoma. The new tumor was also surgically removed but was then referred to histopathological evaluation for diagnostic confirmation, grading and evaluation of surgical margins. The tumor was classified as an infiltrative subcutaneous mastocytoma presenting, additionally, compromised surgical margins. After its excision, the association with a chemotherapy treatment using a protocol of Vimblastina 2 mg/m², i.v. in unique dosage per section, associated with Predinisona 1 mg/kg, v.o, SID was indicated. Each section was realized with an interval of 7 days in between. Only 2 chemotherapy sessions took place. Because of the worsening of the clinical condition associated with a very weakened animal the veterinarian opted for the euthanasia of the animal. Discussion: The diagnostic of mastocytoma must be realized through the association of cytology and histopathology, in case histopathological evaluation is needed to confirm the obtained cytology result, to grade the tumor and to evaluate the compromising of surgical margins. In this sense, it was observed that the bitch was submitted only to cytology diagnostic when it presented the nodule in the ear pavilion. Yet, at the second approach realized by the oncologist, it was possible to realize adequate diagnose methods. However, the animal was not submitted to clinical staging of the mastocytoma due to the non-authorization of the exam by the tutor. Such measure is very important, as it reflects directly in the treatment and prognostic of the animal. Thus, image exams such as abdominal ultrasonography and chest X-ray should have been realized, as well as cytological and histopathological evaluation of the regional lymph nodes, in order to search for metastasis points in these places. As the data suggests, the importance of clinical staging of animals affected by this neoplasia and the importance of cytological evaluation associated with histopathology for a correct diagnosis, prognosis and mastocytoma treatment is noted. It is emphasized that many times veterinarians face impediment related to requesting all necessary exams coming from tutors, which compromises treatment success.

Cutaneous mast cell tumor in a captive Bush dog (Speothos venaticus): pathological and immunophenotypical aspects - case report / Mastocitoma cutâneo em um cachorro-do-mato vinagre (Speothos venaticus) de cativeiro: aspectos patológicos e imunofenotípicos - relato de caso

A senile male captive bush dog (Speothos venaticus) presented a small perianal cutaneous nodule. Histologically, there was an ulcerated round cell tumor composed of well differentiated mast cells with abundant intracytoplasmic purple Giemsa-positive granules, with a diffuse eosinophilic infiltrate. Immunohistochemistry revealed that 30% of the neoplastic cells were positive for Kit in the cytoplasm and cell membrane, and all neoplastic cells were negative for MAC and CD3. Less than 10% of the neoplastic cells were positive for Ki67. At necropsy other primary tumors were identified in this animal, including an intestinal adenoma, an adrenal cortex adenoma and a testicular interstitial cell tumor.(AU)

Um cachorro-vinagre (Speothos venaticus) apresentou um nódulo cutâneo pequeno na região perianal. Histologicamente havia neoplasia cutânea de células redondas e ulcerada, constituída por mastócitos bem diferenciados, com abundantes grânulos citoplasmáticos metacromáticos na coloração de Giemsa e infiltrado eosinofílico difuso. A imuno-histoquímica demonstrou que 30% das células neoplásicas eram positivas para a proteína Kit no citoplasma e na membrana celular. As células foram negativas para MAC e CD3. Menos de 10% das células neoplásicas foram positivas para Ki67. Durante a necropsia, foram identificados outros tumores primários, como adenoma intestinal, adenoma cortical da adrenal e tumor de células intersticiais do testículo.(AU)

Systemic mastocytosis with terminal leukemic manifestation in two dogs

Systemic mastocytosis (SM) with leukemic manifestation is rarely reported in veterinary patients. Here, we describe two cases of systemic mastocytosis with leukemic spread of neoplastic mast cells in adult dogs, including their clinical signs, clinical and anatomic pathology, and immunohistochemical analysis of c-KIT as a diagnostic tool. In both cases, hematologic examination revealed normocytic and normochromic anaemia, leucocytosis with segmented neutrophils, and mastocytosis. Cytological analyses of the peritoneal fluid revealed many neoplastic mast cells. Case 1 was associated with a subcutaneous mast cell tumor and Case 2 was not associated with a cutaneous or subcutaneous mast cell tumor. Neoplastic mast cells were found in the lymph nodes, spleen, liver, and kidneys, and a diagnosis of visceral mastocytosis was established. SM with terminal leukemic manifestation was confirmed by the mastocythemia intensity associated with the morphological changes of the mast cells in the blood and bone marrow.

Systemic mastocytosis with terminal leukemic manifestation in two dogs

Systemic mastocytosis (SM) with leukemic manifestation is rarely reported in veterinary patients. Here, we describe two cases of systemic mastocytosis with leukemic spread of neoplastic mast cells in adult dogs, including their clinical signs, clinical and anatomic pathology, and immunohistochemical analysis of c-KIT as a diagnostic tool. In both cases, hematologic examination revealed normocytic and normochromic anaemia, leucocytosis with segmented neutrophils, and mastocytosis. Cytological analyses of the peritoneal fluid revealed many neoplastic mast cells. Case 1 was associated with a subcutaneous mast cell tumor and Case 2 was not associated with a cutaneous or subcutaneous mast cell tumor. Neoplastic mast cells were found in the lymph nodes, spleen, liver, and kidneys, and a diagnosis of visceral mastocytosis was established. SM with terminal leukemic manifestation was confirmed by the mastocythemia intensity associated with the morphological changes of the mast cells in the blood and bone marrow.(AU)

Bone marrow bi-hypoplasia in a dog with a sertoli cell tumor / Hipoplasia dupla de medula óssea em um cão com tumor de células de sertoli

A 20-year-old unneutered male poodle presented prostration, apathy, staggering gait, lack of appetite and tick infestation. The dog was diagnosed with a Sertoli cell tumor in an undescended testicle by cytological, histopathological and immunohistochemical tests. Pancytopenia with moderate nonregenerative anemia, leukopenia and severe thrombocytopenia were detected in the complete blood count. Cytological and histopathological evaluation of the bone marrow revealed a cellularity of 30%, with erythroid (59%), lymphoid (40%) and mast cells (1%), and an absence of granulocytic, monocytic and megakaryocytic lineage cells. In post-mortem examinations, changes related to hemostatic disorders were found. The absence of microorganisms in molecular tests and an estrogen serum concentration over reference values confirmed hyperestrogenism as a possible cause of pancytopenia. The literature describes a Sertoli cell tumor hyperestrogenism that induced pancytopenia, along with bone marrow hypoplasia of all hematopoietic lineages. In contrast, in the present case, the erythroid precursor cells were preserved in the bone marrow, although there were no reticulocytes circulating in the blood. This case, therefore, should be considered in future investigations of pancytopenia induced by Sertoli cell tumor hyperestrogenism.(AU)

Um cão Poodle, macho, de 20 anos, não castrado, apresentou prostração, apatia, andar cambaleante, falta de apetite e infestação por carrapatos. Nesse animal, foi diagnosticado tumor de células de Sertoli em um testículo não descendente, utilizando-se citologia, histopatologia e imuno-histoquímica. Pancitopenia com anemia moderada não regenerativa, leucopenia e trombocitopenia intensas foram detectadas no hemograma. Na avaliação citológica e histopatológica da medula óssea, havia celularidade de 30%, constituída pelas linhagens eritroide (59%) e linfoide (40%) e por mastócitos (1%), com ausência de células das linhagens granulocítica, monocítica e megacariocítica. Em exames post mortem, mudanças relacionadas à hemostasia foram encontradas. A ausência de micro-organismos nos testes moleculares e a concentração sérica de estrogênio acima dos valores de referência confirmaram hiperestrogenismo como a possível causa da pancitopenia. A literatura descreve hiperestrogenismo em tumores de células de Sertoli induzindo pancitopenia associada com hipoplasia da medula óssea de todas as linhagens hematopoiéticas. Em contraste, no presente caso, as células precursoras eritróides estavam preservadas na medula óssea, embora não houvesse reticulócitos no sangue. Assim, o relato apresentado deve ser considerado em futuras investigações de pancitopenia induzida por hiperestrogenismo em tumor de células de Sertoli.(AU)

Bone marrow bi-hypoplasia in a dog with a sertoli cell tumor / Hipoplasia dupla de medula óssea em um cão com tumor de células de sertoli

A 20-year-old unneutered male poodle presented prostration, apathy, staggering gait, lack of appetite and tick infestation. The dog was diagnosed with a Sertoli cell tumor in an undescended testicle by cytological, histopathological and immunohistochemical tests. Pancytopenia with moderate nonregenerative anemia, leukopenia and severe thrombocytopenia were detected in the complete blood count. Cytological and histopathological evaluation of the bone marrow revealed a cellularity of 30%, with erythroid (59%), lymphoid (40%) and mast cells (1%), and an absence of granulocytic, monocytic and megakaryocytic lineage cells. In post-mortem examinations, changes related to hemostatic disorders were found. The absence of microorganisms in molecular tests and an estrogen serum concentration over reference values confirmed hyperestrogenism as a possible cause of pancytopenia. The literature describes a Sertoli cell tumor hyperestrogenism that induced pancytopenia, along with bone marrow hypoplasia of all hematopoietic lineages. In contrast, in the present case, the erythroid precursor cells were preserved in the bone marrow, although there were no reticulocytes circulating in the blood. This case, therefore, should be considered in future investigations of pancytopenia induced by Sertoli cell tumor hyperestrogenism.(AU)

Um cão Poodle, macho, de 20 anos, não castrado, apresentou prostração, apatia, andar cambaleante, falta de apetite e infestação por carrapatos. Nesse animal, foi diagnosticado tumor de células de Sertoli em um testículo não descendente, utilizando-se citologia, histopatologia e imuno-histoquímica. Pancitopenia com anemia moderada não regenerativa, leucopenia e trombocitopenia intensas foram detectadas no hemograma. Na avaliação citológica e histopatológica da medula óssea, havia celularidade de 30%, constituída pelas linhagens eritroide (59%) e linfoide (40%) e por mastócitos (1%), com ausência de células das linhagens granulocítica, monocítica e megacariocítica. Em exames post mortem, mudanças relacionadas à hemostasia foram encontradas. A ausência de micro-organismos nos testes moleculares e a concentração sérica de estrogênio acima dos valores de referência confirmaram hiperestrogenismo como a possível causa da pancitopenia. A literatura descreve hiperestrogenismo em tumores de células de Sertoli induzindo pancitopenia associada com hipoplasia da medula óssea de todas as linhagens hematopoiéticas. Em contraste, no presente caso, as células precursoras eritróides estavam preservadas na medula óssea, embora não houvesse reticulócitos no sangue. Assim, o relato apresentado deve ser considerado em futuras investigações de pancitopenia induzida por hiperestrogenismo em tumor de células de Sertoli.(AU)

Involvement of mast cells, CD68+ and VEGF+ expressions in response to Himatanthus drasticus commercial latex in mice wound healing model / Envolvimento de mastócitos, expressão de CD68+ e VEGF+ em resposta ao látex comercial de Himatanthus drasticus em modelo de cicatrização em camundongos

This study aimed to evaluate Himatanthus drasticus latex in a mice wound healing experimental model. Animals were divided into four groups (n=7) according to the treatments: GI - saline 0.9% (control), GII - mineral oil (vehicle), GIII - H. drasticus commercial latex (HdCL) and GIV - H. drasticus mixed isolated fraction (MIF, 1 mg/mL). The treatments were applied topically once daily, 50 µL for 14 consecutive days. Macroscopic lesions were evaluated, considering parameters such as swelling, redness, granulation tissue and reepithelialization. VEGF+, CD68+ expressions and mast cells (Toluidin blue stain) were evaluated. HdCL induced higher contraction and exuberant granulation tissue (P > 0.05). HdCL showed a mild inflammatory process while MIF induced intense infiltrate inflammatory predominantly by lymphocytes, vascular congestion, bleeding and did not presented full reepithelialization. Reorganization of collagen fibers (red picrosirius stain) was observed. CD68+ expression and mast cells were presented as moderate, intense and mild in GI, GIII and GIV, respectively. Neovascularization occurred in all groups, while VEGF+ expression was intense in MIF in relation to HdCL. We concluded that HdCL presents wound healing potential, through modulation of mast cells, CD68+ and VEGF+ expressions that can be associated to triterpenes presence according MIF isolated from HdCL.(AU)

Objetivou-se avaliar o látex de Himatanthus drasticus em feridas induzidas experimentalmente em camundongos. Os animais foram divididos em quatro grupos (n=7): GI - salina 0,9% (controle), GII - óleo mineral (veículo), GIII - látex comercial de H. drasticus (HdCL) e GIV - fração isolada mista de H. drasticus (MIF, 1mg/mL). Os tratamentos foram aplicados topicamente uma vez ao dia (50µL), durante 14 dias consecutivos. Lesões macroscópicas, as expressões de VEGF+, CD68+ e a participação dos mastócitos (coloração azul de toluidina) foram avaliadas. HdCL induziu maior contração e tecido de granulação exuberante (P >0,05). HdCL induziu leve processo inflamatório enquanto MIF promoveu intenso infiltrado inflamatório predominantemente linfocítico, congestão vascular, hemorragia e reepitelização parcial. Observou-se reorganização das fibras colágenas (coloração picrosírius). A expressão de CD68+ e os mastócitos apresentaram-se moderados, intensos e leves em GI, GIII e GIV, respectivamente. A neovascularização foi observada em todos os grupos, enquanto a expressão de VEGF+ foi mais intensa em MIF em relação a HdCL. Conclui-se que HdCL apresenta potencial de cicatrização por meio da modulação dos mastócitos e das expressões de CD68+ e VEGF+, o que pode estar associado à presença de triterpenos de acordo com MIF isolada de HdCL.(AU)

Involvement of mast cells, CD68+ and VEGF+ expressions in response to Himatanthus drasticus commercial latex in mice wound healing model / Envolvimento de mastócitos, expressão de CD68+ e VEGF+ em resposta ao látex comercial de Himatanthus drasticus em modelo de cicatrização em camundongos

This study aimed to evaluate Himatanthus drasticus latex in a mice wound healing experimental model. Animals were divided into four groups (n=7) according to the treatments: GI - saline 0.9% (control), GII - mineral oil (vehicle), GIII - H. drasticus commercial latex (HdCL) and GIV - H. drasticus mixed isolated fraction (MIF, 1 mg/mL). The treatments were applied topically once daily, 50 µL for 14 consecutive days. Macroscopic lesions were evaluated, considering parameters such as swelling, redness, granulation tissue and reepithelialization. VEGF+, CD68+ expressions and mast cells (Toluidin blue stain) were evaluated. HdCL induced higher contraction and exuberant granulation tissue (P > 0.05). HdCL showed a mild inflammatory process while MIF induced intense infiltrate inflammatory predominantly by lymphocytes, vascular congestion, bleeding and did not presented full reepithelialization. Reorganization of collagen fibers (red picrosirius stain) was observed. CD68+ expression and mast cells were presented as moderate, intense and mild in GI, GIII and GIV, respectively. Neovascularization occurred in all groups, while VEGF+ expression was intense in MIF in relation to HdCL. We concluded that HdCL presents wound healing potential, through modulation of mast cells, CD68+ and VEGF+ expressions that can be associated to triterpenes presence according MIF isolated from HdCL.(AU)

Objetivou-se avaliar o látex de Himatanthus drasticus em feridas induzidas experimentalmente em camundongos. Os animais foram divididos em quatro grupos (n=7): GI - salina 0,9% (controle), GII - óleo mineral (veículo), GIII - látex comercial de H. drasticus (HdCL) e GIV - fração isolada mista de H. drasticus (MIF, 1mg/mL). Os tratamentos foram aplicados topicamente uma vez ao dia (50µL), durante 14 dias consecutivos. Lesões macroscópicas, as expressões de VEGF+, CD68+ e a participação dos mastócitos (coloração azul de toluidina) foram avaliadas. HdCL induziu maior contração e tecido de granulação exuberante (P >0,05). HdCL induziu leve processo inflamatório enquanto MIF promoveu intenso infiltrado inflamatório predominantemente linfocítico, congestão vascular, hemorragia e reepitelização parcial. Observou-se reorganização das fibras colágenas (coloração picrosírius). A expressão de CD68+ e os mastócitos apresentaram-se moderados, intensos e leves em GI, GIII e GIV, respectivamente. A neovascularização foi observada em todos os grupos, enquanto a expressão de VEGF+ foi mais intensa em MIF em relação a HdCL. Conclui-se que HdCL apresenta potencial de cicatrização por meio da modulação dos mastócitos e das expressões de CD68+ e VEGF+, o que pode estar associado à presença de triterpenos de acordo com MIF isolada de HdCL.(AU)

Mastocitoma cutâneo em felino – relato de caso / Feline mast cell tumor – case report

O mastocitoma é descrito como a segunda neoplasia cutânea mais comum em felinos, porém no Brasil encontramos poucos relatos nessa espécie. O objetivo do estudo foi relatar um caso de mastocitoma cutâneo em um felino pelo curto brasileiro, macho, de oito anos, atendido no Setor de Dermatologia do Hospital Veterinário da Universidade Federal Rural do Rio de Janeiro que apresentava nódulo único, eritematoso, alopécico e ulcerado na região supraorbitária esquerda. O exame citológico revelou a presença de uma grande quantidade de mastócitos neoplásicos bem diferenciados. O animal foi encaminhado para a remoção cirúrgica do nódulo. O resultado histopatológico confirmou o diagnóstico de mastocitoma. Conclui-se que a citologia é uma importante ferramenta para o diagnóstico da neoplasia em felinos e que o procedimento cirúrgico é a terapia de eleição.

The mast cell tumor is described as the second most common skin neoplasm in cats, but in Brazil we found few reports in this species. The aim of the study is to report a case of cutaneous mast cell tumor in an eight years, male, short hair Brazilian feline attended at the Dermatology Service of the Veterinary Hospital of the University Federal Rural of Rio de Janeiro that had a single nodule, erythematosus, alopecic and ulcerated in the left supraorbital region. Cytological examination revealed the presence of a lot of well-differentiated neoplastic mast cells. The animal was taken to the surgical removal of the nodule. Histopathological examination confirmed the diagnosis of mast cell tumor. It is concluded that cytology is an important tool for the diagnosis of this neoplasm in cats and that surgery is the preferred therapy.

Mastocitoma cutâneo em felino relato de caso / Feline mast cell tumor case report

O mastocitoma é descrito como a segunda neoplasia cutânea mais comum em felinos, porém no Brasil encontramos poucos relatos nessa espécie. O objetivo do estudo foi relatar um caso de mastocitoma cutâneo em um felino pelo curto brasileiro, macho, de oito anos, atendido no Setor de Dermatologia do Hospital Veterinário da Universidade Federal Rural do Rio de Janeiro que apresentava nódulo único, eritematoso, alopécico e ulcerado na região supraorbitária esquerda. O exame citológico revelou a presença de uma grande quantidade de mastócitos neoplásicos bem diferenciados. O animal foi encaminhado para a remoção cirúrgica do nódulo. O resultado histopatológico confirmou o diagnóstico de mastocitoma. Conclui-se que a citologia é uma importante ferramenta para o diagnóstico da neoplasia em felinos e que o procedimento cirúrgico é a terapia de eleição.(AU) 

The mast cell tumor is described as the second most common skin neoplasm in cats, but in Brazil we found few reports in this species. The aim of the study is to report a case of cutaneous mast cell tumor in an eight years, male, short hair Brazilian feline attended at the Dermatology Service of the Veterinary Hospital of the University Federal Rural of Rio de Janeiro that had a single nodule, erythematosus, alopecic and ulcerated in the left supraorbital region. Cytological examination revealed the presence of a lot of well-differentiated neoplastic mast cells. The animal was taken to the surgical removal of the nodule. Histopathological examination confirmed the diagnosis of mast cell tumor. It is concluded that cytology is an important tool for the diagnosis of this neoplasm in cats and that surgery is the preferred therapy.(AU)

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.

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.

AVALIAÇÃO DA EXPRESSÃO DA VIA PD-1/PDL-1 E DAS PROTEÍNAS CTLA-4, RANK-RANK-L E IFN-y EM MASTOCITOMAS CUTÂNEOS DE ALTO GRAU EM CÃES: NOVAS PERSPECTIVAS DE USO DA IMUNOTERAPIA

Os mastócitos caninos são considerados os tumores malignos cutâneos mais frequentes. São potencialmente metastáticos. A escolha do tratamento dependerá da presença ou ausência dos fatores prognósticos negativos, incluindo metástases dos linfonodos regionais, entretanto, até o momento não existe um marcador prognóstico aplicado em linfonodos que pudesse estar associado aos demais fatores prognósticos. A imunoterapia em medicina veterinária está sendo desenvolvida recentemente. Os pontos de controle imunológicos (CTLA-4, PD-1 / PD-L1) desempenham um papel vital na inibição das respostas imunes e na promoção da auto-tolerância através da modulação da atividade das células T, ativando a apoptose de células T específicas do antígeno e inibindo a apoptose de células T regulatórias. Estratégias terapêuticas que modulam o microambiente tumoral e reforçam a migração de células T para o tumor são fundamentais no controle de diversos tipos de câncer. Uma dessas estratégias é o uso de moduladores da imunidade inata, como os agonistas do receptor toll-like (TLRs). Nesse cenário, a nanoimunoterapia Onco- Therad induz a via de sinalização do interferon mediada por TLR4, resultando em potentes efeitos antitumorais. Além disso, a inibição da via de sinalização RANK / RANK-L regulou negativamente a expressão de PD-1 / PD-L1 no microambiente tumoral. O objetivo deste estudo é avaliar a expressão dos checkpoints e anticorpos RANK - RANK-L e IFN- em MCT de alto grau e correlacionados com a expressão de PD-1 / PD-L1 em linfonodos associada a características clínicas.

Canine mast cell tumors (MCTs) being considered the most frequent cutaneous malignant tumor. Are potentially metastatic. The choice of treatment will depend of the presence or absence of negative prognostic factors, including regional lymph nodes metastasis, however, until now does not exist a prognostic marker applied in lymph nodes that could be associated with the others prognostic factors. Immunotherapy in veterinary medicine recently being developed. The immune checkpoints (CTLA-4 , PD-1/PD-L1) plays a vital role in inhibiting immune responses and promoting self-tolerance through modulating the activity of T-cells, activating apoptosis of antigen-specific T cells and inhibiting apoptosis of regulatory T cells. Therapeutic strategies that modulate the tumor microenvironment and reinforce the migration of T cells to the tumor are fundamental in the control of several types of cancers. One of these strategies is the use of innate immunity modulators, such as agonists of toll-like receptor (TLRs). In this scenario, OncoTherad nano-immunotherapy induces TLR4-mediated interferon signaling pathway, resulting in potent antitumor effects. Also, inhibition of RANK/ RANK-L signaling pathway downregulated PD-1/PD-L1 expression on tumor microenvironment. The main of this study is evaluate the expression of checkpoints and antibodies RANK - RANK-L and IFN- in MCT high grade and correlated with the expression of PD-1/PD-L1 in lymph nodes associated with clinical characteristics.

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%).

RELAÇÃO MASTÓCITOS E ANGIOGÊNESE EM NEOPLASIAS MAMÁRIAS CANINAS

As neoplasias mamárias são o tipo tumoral mais frequente em cadelas e mulheres. As cadelas são consideradas excelente modelo espontâneo no estudo do câncer de mama. O microambiente tumoral tem sido estudado nos últimos anos para maior compreensão do desenvolvimento e progressão dessa doença. Os mastócitos são um tipo celular presente neste microambiente que podem promover as neoplasias por meio da liberação de fatores pró-angiogênicos presentes em seus grânulos. Do mesmo modo, a fibrose tumoral tem sido considerada como fator prognóstico em diferentes tipos de tumores. O presente trabalho objetiva verificar a relação entre mastócitos e angiogênese em neoplasias mamárias benignas e malignas avaliando o papel da degranulação e da microlocalização dos mastócitos em neoplasias mamárias caninas. As mamas avaliadas foram divididas em três grupos: grupo controle (n=46); grupo maligno (n=57) e grupo benigno (n=19). Também foram avaliados linfonodos sem alterações (n=59) e com metástases (n=6). A marcação de mastócitos, vasos sanguíneos e fibrose tumoral foram realizados por técnicas histoquímicas e avaliadas por software ImageJ versão 1.42q. A densidade total de vasos (P=0,03) e vasos peritumorais (P=0,05) foram maiores no grupo maligno. Houve ainda correlação positiva entre densidade de vasos intratumorais e totais e densidade de mastócitos. Diante desses achados pode ser concluído que uma maior densidade de mastócitos está relacionada à maior densidade de vasos sanguíneos e que estes são mais abundantes em neoplasias malignas reforçando o papel crucial da angiogênese no desenvolvimento neoplásico.

The mammary neoplasias are the most often tumor type in bitchs and women. Female dogs are considered an excelent spontaneous model in the breast cancer study. The tumor microenvironment has been studied in the recent years to a greater understanding of the development and progression of this disease. Mast cells are a cell type present in this microenvironment that can promote neoplasms by releasing pro-angiogenic factors present in their granules. Likewise, tumor fibrosis has been considered a prognostic factor in different types of tumors. The present work aims to verify the connection between mast cells and angiogenesis in different histological types of mammary tumors by measuring the role of degranulation and microlocation in canine mammary glands tumors. The analyzed mammary glands were splitted into three 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. The staining of the mast cells, the blood vessels and the tumor fibrosis were performed by histochemical techniques and evaluated by ImageJ software version 1.42q. The total density of vessels (p = 0.03) and peritumoral vessels (p = 0.05) were higher in the malignant group. There was even a positive correlation between the intratumoral and total vessels and the mast cell density. In the face of these findings, we can conclude that a higher density of mast cells is related to a higher density of blood vessels and that these are more abundant in malignant neoplasms reinforcing the crucial role of angiogenesis in neoplastic development.

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