Cutaneous non-epitheliotropic large T-cell lymphoma in an English Bulldog

Cutaneous lymphoma is histologically classified in epitheliotropic and non-epitheliotropic, the first showing higher incidence in dogs, and the second, in cats. Non-epitheliotropic lymphoma presents lymphocyte aggregates in the dermis and subcutaneous tissue, however cutaneous annexes are not infiltrated. It is usually more aggressive than epitheliotropic lymphomas. The aim of this study was to report a case of non-epitheliotropic lymphoma in a 9-year-old, female, English Bulldog presented with non-ulcerated skin nodules adhered to deep tissues. Microscopic and immunophenotypic features supported the diagnosis of non-epitheliotropic large T-cell lymphoma. Treatment was initiated with modification of the LOPP protocol, replacing procarbazine by dacarbazine (600 mg/m²) for up to six cycles, with a three-month survival. In the 11th week of treatment, after recurrent episodes of vomiting and diarrhea, abdominal ultrasound was performed and revealed an infiltrative mass in the stomach’s greater curvature topography, showing an expansive and accentuated increase in one week, when euthanasia was elected.

Cutaneous non-epitheliotropic large T-cell lymphoma in an English Bulldog

Cutaneous lymphoma is histologically classified in epitheliotropic and non-epitheliotropic, the first showing higher incidence in dogs, and the second, in cats. Non-epitheliotropic lymphoma presents lymphocyte aggregates in the dermis and subcutaneous tissue, however cutaneous annexes are not infiltrated. It is usually more aggressive than epitheliotropic lymphomas. The aim of this study was to report a case of non-epitheliotropic lymphoma in a 9-year-old, female, English Bulldog presented with non-ulcerated skin nodules adhered to deep tissues. Microscopic and immunophenotypic features supported the diagnosis of non-epitheliotropic large T-cell lymphoma. Treatment was initiated with modification of the LOPP protocol, replacing procarbazine by dacarbazine (600 mg/m²) for up to six cycles, with a three-month survival. In the 11th week of treatment, after recurrent episodes of vomiting and diarrhea, abdominal ultrasound was performed and revealed an infiltrative mass in the stomachs greater curvature topography, showing an expansive and accentuated increase in one week, when euthanasia was elected.(AU)

Immunohistochemical study of genital and extragenital forms of canine transmissible venereal tumor in Brazil / Estudo imuno-histoquímico de formas genitais e extragenitais do tumor venéreo transmissível canino no Brasil

Aiming to provide insight and discussing the problems related to the diagnosis and differential diagnosis of canine transmissible venereal tumor (CTVT), especially in its extragenital form, immunohistochemical evaluation was performed and a comparison was established by analysis of the microscopic appearance of 10 genital CTVTs and 13 exclusively extragenital CTVTs previously diagnosed by cytology and histopathology. CTVTs samples were incubated with biotinylated antibodies raised against specific membrane (anti-macrophage) and cytoplasmic antigens (anti-lysozyme, anti-S-100 protein, anti-vimentin and anti-CD18) and subsequently developed using streptavidin-biotin peroxidase and streptavidin-biotin-alkaline phosphatase methods. A strong reactivity with the anti-vimentin antibody was found in 100% of the tumors tested (22/22). No reactivity was found for the anti-lysozyme, anti-macrophage, anti-S-100 protein and anti-CD18. No histopathological or immunoreactivity differences between genital and extragenital CTVTs were found. These findings do not corroborate the hypothesis of histiocytic origin of CTVT (no reactivity to anti-lysozyme, anti-macrophage and anti-CD 18 antibodies). In addition, the antibody panel used is useful to narrow the differential diagnosis for lymphomas, histiocytic tumors, amelanotic melanomas, and poorly differentiated epithelial neoplasias, among others.(AU)

Com a finalidade de fornecer subsídios e discutir os problemas referentes ao diagnóstico e ao diagnóstico diferencial do tumor venéreo transmissível canino (TVTC), principalmente em sua forma extragenital, foi realizada a avaliação imuno-histoquímica e estabelecido termo de comparação com o aspecto microscópico em 10 TVTCs genitais e em 13 exclusivamente extragenitais previamente diagnosticados através de citologia e histopatologia. Os TVTCs foram testados para reagentes específicos de antígenos de membrana (anti-macrófago) e citoplasmáticos (anti-lisozima, anti-proteína S-100, anti-alfa-1-antitripsina, anti-vimentina e anti-CD18) com a utilização da técnica complexo avidina-biotina-peroxidase e estreptavidina-biotina-fosfatase Em 100% dos tumores testados (22/22) com anticorpo anti-vimentina houve forte imuno-reatividade. Não houve reatividade para os anticorpos anti-lisozima, anti-macrófago, anti-proteína S-100 e anti-CD18. Não houve diferença histopatológica e de imuno-reatividade entre os TVTCs genitais e extragenitais. Estes achados indicam que os TVTCs avaliados não são de origem histiocítica (ausência de reatividade dos anticorpos anti-lisozima, anti-macrófago e anti-CD18). O painel de anticorpos utilizado é útil para o diagnóstico diferencial deste tumor com linfomas, tumores histiocíticos, melanomas amelanóticos e neoplasias de origem epitelial pobremente diferenciadas, entre outros.(AU)

Morphological patterns and malignancy criteria of transmissible venereal tumor in cytopathological and histopathological exams / Padrões morfológicos e critérios de malignidade do tumor venéreo transmissível aos exames citopatológico e histopatológico

The aim of this study was to identify morphological patterns and malignancy criteria of the TVT in cytopathological and histopathological evaluations and relate these characteristics to clinical evolution and response to chemotherapy. Regarding studied animals, sixteen dogs were female and four were male. The age of the animals ranged between one and ten years old. Considering breed, 80% of the dogs were mongrel dogs and 20% were of other breeds. It was found that the cytological samples allowed a better characterization of the cell type than histological ones. The plasmacytoid was the most common morphological type of TVT, followed by the lymphocytoid and mixed standards. There was no difference among the scores for the malignancy criteria and morphological types of TVT. Regarding response to chemotherapy, no morphological type of the TVT showed any difference, but the TVT presents morphological peculiarities that may interfere with tumor behavior, especially those related to increased aggressiveness and that are observed in the plasmacytoid TVT.(AU)

Este estudo teve por objetivo identificar os padrões morfológicos e os critérios de malignidade do TVT aos exames citológico e histopatológico e relacionar essas características à evolução clínica e à resposta à quimioterapia. Dos ani- mais estudados, dezesseis cães eram fêmeas e quatro machos. A idade dos animais variou entre um e dez anos de idade. Quanto à raça, 80% dos cães eram sem raça definida e 20% de outras raças. Constatou-se que as amostras citológicas permitiram melhor caracterização do tipo celular do que as histológicas. O TVT tipo plasmocitoide foi o de maior ocor- rência, seguido pelos padrões linfocitoide e misto. Não houve diferença entre os escores estabelecidos para os critérios de malignidade e os tipos do TVT. Nenhum tipo morfológico do TVT diferiu quanto à resposta quimioterápica, mas o TVT apresenta particularidades morfológicas que podem interferir no comportamento tumoral, especialmente aquelas relacionadas à maior agressividade, e que são observadas no TVT plasmocitoide.(AU)