First description of basaloid carcinoma of the canine mammary gland: case report / Primeira descrição do carcinoma basaloide da glândula mamária canina: relato de caso

The objective of this case report was to describe histopathological and immunohistochemical characteristics of the first reported basaloid carcinomas in the canine mammary gland. Two bitches were treated for tumors in the mammary gland and underwent mastectomy. Microscopic evaluation of these tumors revealed epithelial cells arranged in a predominantly solid pattern with hyperchromatic peripheral cells arranged in a palisade pattern. Metastases in regional lymph nodes were found in both animals, and one bitch exhibited pulmonary metastasis. Immunohistochemistry revealed positive labeling for the basal cell markers cytokeratin 14 and p63. Histopathological and immunohistochemical findings led to diagnoses of basaloid carcinoma of the canine mammary gland with regional and distant metastasis.(AU)

O objetivo deste relato de caso é descrever as características histopatológicas e imuno-histoquímicas do primeiro relato de carcinoma basaloide na glândula mamária canina. Duas cadelas foram atendidas com tumores na glândula mamária e foram submetidas à mastectomia. A avaliação microscópica demonstrou células epiteliais arranjadas em um padrão predominantemente sólido, com células periféricas hipercromáticas, dispostas em paliçada. As duas apresentaram metástase em linfonodos regionais e uma delas metástase pulmonar. A imuno-histoquímica revelou marcação positiva para citoqueratina 14 e p63, marcadores de células basais. Achados histopatológicos e imuno-histoquímicos levaram ao diagnóstico de carcinoma basaloide da glândula mamária canina com metástase regional e a distância.(AU)

Tumor-associated macrophage is correlated with survival and SOCS protein expression in canine mammary carcinoma / Correlação do infiltrado macrofágico com a sobrevida e a expressão da proteína SOCS no carcinoma mamário canino

The inflammatory infiltrate in the tumor microenvironment, particularly in mammary tumors, has aroused great interest in oncology, to play different roles in the progression or tumor regression dependent on the types and cell subsets involved. The present study aimed to evaluate (1) the occurrence and intensity of macrophage infiltration in the mammary carcinoma microenvironment, (2) the expression of SOCS1 and SOCS3 proteins in tumor associated macrophages, (3) any association between these parameters and tumor development, as well as survival rates in female dogs. Twenty-two female dogs diagnosed as carcinoma arising in a mixed tumor (CMT) by histopathology were divided into two groups following mastectomy: dogs without metastasis (CMT(-)=11) and those with metastasis (CMT(+)=11). The following parameters were analyzed: tumor size, lymph node metastasis, clinical stage, histological grade, distribution and intensity of inflammatory infiltrate, tumor macrophage quantification by immunohistochemical analysis of SOCS1 and SOCS3 expression, and immunophenotyping of peripheral blood leukocytes by flow cytometry. Dogs with the higher proportions of macrophages in the inflammatory infiltrate (≥400/tumor) also had higher survival rates in comparison with dogs with less macrophages. Immunostaining revealed higher proportions of SOCS3-positive macrophages in dogs without lymph node metastasis, while SOCS1-positive macrophages were predominant in dogs with metastasis (p<0.05). Multivariate analysis found associations between survival rate and clinical staging (p=0.025), histological grade (p=0.007), and the expression of MHC-CI in circulating monocytes (p=0.018). Higher SOCS3 expression in activated macrophages within the inflammatory infiltrate were considered indicative of an antitumor immune response, improved clinicopathological parameters and longer survival, whereas SOCS1-related activation was associated with tumor progression, metastasis development and reduced survival in female dogs with mammary carcinomas.(AU)

O infiltrado inflamatório no microambiente tumoral, particularmente nos tumores mamários, tem despertado grande interesse na oncologia, por desempenhar diferentes funções na progressão ou regressão tumoral, dependendo dos tipos e subtipos celulares envolvidos. O presente estudo teve como objetivo avaliar: (1) a ocorrência e a intensidade do infiltrado macrofágico no microambiente do carcinoma mamário; (2) a expressão das proteínas SOCS1 e SOCS3 nos macrófagos associados ao tumor; (3) qualquer associação relacionada ao prognóstico entre estes parâmetros e o desenvolvimento tumoral, assim como a taxa de sobrevida. Vinte e duas cadelas diagnosticadas com carcinoma em tumor misto (CTM) por exame histopatológico foram divididas em dois grupos após a mastectomia: cadelas sem metástase (CTM(-)=11) e cadelas com metástase (CTM(+)=11). Foram analisados os seguintes parâmetros: tamanho do tumor, metástase para linfonodo, estadiamento clínico, grau histológico, distribuição e intensidade do infiltrado inflamatório, quantificação dos macrófagos tumorais por análise imuno-histoquímica da expressão de SOCS1 e SOCS3, e imunofenotipagem dos leucócitos (monócitos e linfócitos) do sangue periférico por citometria de fluxo. Cadelas que apresentavam maiores proporções de macrófagos no infiltrado inflamatório (≥400/tumor) também tiveram maior taxa de sobrevida em comparação àquelas com menos macrófagos. A imunomarcação revelou maiores proporções de macrófagos SOCS3-positivos em cães sem metástase para linfonodo, enquanto que macrófagos SOCS1-positivos foram predominantes naqueles com metástase (p<0,05). A análise multivariada identificou associações entre a taxa de sobrevida e o estadiamento clínico (p=0,025), grau histológico (p=0,007) e a expressão de MHC-CI em monócitos circulantes (p=0,018). A maior expressão de SOCS3 nos macrófagos ativados foi considerada indicativa de uma resposta imune antitumoral, melhores parâmetros clínicos e maior taxa de sobrevida, ao passo que a ativação relacionada com SOCS1 foi associada à progressão tumoral, desenvolvimento de metástase e redução na taxa de sobrevida em cadelas com carcinoma mamário.(AU)

Imunomarcação da transição epitélio-mesenquima na neoplasia mamária primária de cadelas e sua metástase em linfonodo / Epithelial to mesenchymal transition immunostaining in canine primary mammary tumor and lymph node

Os carcinomas mamários em cães apresentam alta capacidade metastática o que confere menor sobrevida para os pacientes com este tipo de neoplasia. O fenótipo transição epitélio-mesênquima, caracterizado pela troca dos filamentos intermediários de citoqueratina por vimentina, além da perda da proteína de adesão entre células (E-caderina) está relacionado com a maior ocorrência de metástase. Diante disto, objetivou-se avaliar, por meio de imunomarcações, a expressão de vimentina, citoqueratina e E-caderina nos tumores mamários caninos e suas metástases em linfonodo, a fim de avaliar o comportamento celular frente a esta neoplasia. Foram analisados cinco casos de neoplasias mamárias primárias caninas e suas respectivas metástases em linfonodos. Foram comparadas as médias de imunomarcações do grupo de neoplasias primárias com as médias do grupo metástase. Não houve diferença estatística nas imunomarcações da citoqueratina (p=0,1407) e E-caderina (p= 0,312) entre os grupos, apesar da média de expressão da E-caderina ter sido maior no grupo de metástases. A expressão da vimentina foi maior nos sítios das metástases (p=0,0462). Conclui-se que a expressão de vimentina aumenta no foco da metástase em relação aos seus respectivos tumores primários mamários caninos, caracterizando alteração estrutural celular, conferindo um fenótipo transição epitélio-mesênquima. Além da E-caderina apresentar fortes indícios de aumento no foco da metástase caracterizando maior adesão.(AU)

Mammary carcinomas in dogs have a high metastatic capacity which gives a shorter survival rate for patients with this type of tumor. The epithelial-mesenchymal transition phenotype, characterized by the trade of intermediary filaments of cytokeratin by vimentin, also by the loss of the adhesion protein between cells (E-cadherin) is associated with metastasis. Due to this fact, it was aimed to evaluate, by immunostaining, the expression of vimentin, cytokeratin and E-cadherin in canine mammary tumors and the metastasis in lymph node, in order to assess the cell behavior when facing this cancer. Five cases of canine mammary tumors and metastasis in lymph node were evaluated. The averages of immunostainings of the group of primary neoplasms were compared with the averages of the lymph node group. The results showed that immunostaining for cytokeratins (p=0,1407) and E-caderina (p=0,312) were not significant between the groups, despite the expression mean of cadherin was higher in the metastase group. The expression of vimentin (p=0,04) was greater at sites of metastases. It is concluded that the expression of vimentin increases in the focus of the metastase in relation to their respective primary canine mammary tumors, characterizing cellular structural alteration, conferring a transient epithelial-mesenchymal phenotype. And cadherin present strong evidence of increased focus on metastasis characterizing increased adhesion.(AU)

Glycogen-rich clear cell carcinoma of the feline mammary gland: case report / Carcinoma de células claras rico em glicogênio da glândula mamária felina: relato de caso

The aim of this report is to describe the first histopathological, immunohistochemical, and clinical characteristics of a feline glycogen-rich clear cell carcinoma (GRCCC). A Persian queen was admitted with mammary gland tumors and underwent radical unilateral mastectomy. Overall survival was considered 33 days and death was due to clinical evolution of the disease. Microscopic evaluation demonstrated epithelial cells arranged in a predominantly solid pattern, tumor cells presented an ample, granular, and foamy clear cytoplasm, and moderate cellular pleomorfism. The presence of cytoplasmatic glycogen was confirmed through diastase digestion followed by PAS staining. Histopathological and histochemical findings lead to the diagnosis of GRCCC with regional metastases.(AU)

O objetivo deste relato de caso é descrever as características clínicas, histopatológicas e imuno-histoquímicas do primeiro carcinoma mamário de células claras rico em glicogênio em felino. Uma gata persa foi atendida com tumores na glândula mamária e foi submetida à mastectomia radical unilateral. A sobrevida livre de doença foi considerada 33 dias, e o óbito foi devido à evolução da doença. A avaliação microscópica demonstrou células epiteliais arranjadas em um padrão predominantemente sólido, as células tumorais apresentaram um citoplasma claro, amplo, granular e espumoso e pleomorfismo celular moderado. A presença do glicogênio citoplasmático foi confirmada pela digestão pela diástase, seguida da coloração de PAS. Achados histopatológicos e histoquímicos levaram ao diagnóstico de carcinoma de células claras rico em glicogênio felino com metástase regional.(AU)

Increased circulating macrophage migration inhibitory factor levels are associated with coronary artery disease

BACKGROUND: To evaluate the macrophage migration inhibitory factor and E-selectin levels in patients with acute coronary syndrome. MATERIALS/METHODS: We examined the plasma migration inhibitory factor and E-selectin levels in 87 patients who presented with chest pain at our hospital. The patients were classified into two groups according to their cardiac status. Sixty-five patients had acute myocardial infarction, and 22 patients had non-cardiac chest pain (non-coronary disease). We designated the latter group of patients as the control group. The patients who presented with acute myocardial infarction were further divided into two subgroups: ST-elevated myocardial infarction (n = 30) and non-ST elevated myocardial infarction (n = 35). RESULTS: We found higher plasma migration inhibitory factor levels in both acute myocardial infarction subgroups than in the control group. However, the E-selectin levels were similar between the acute myocardial infarction and control patients. In addition, we did not find a significant difference in the plasma migration inhibitory factor levels between the ST elevated myocardial infarction and NST-elevated myocardial infarction subgroups. DISCUSSION: The circulating concentrations of migration inhibitory factor were significantly increased in acute myocardial infarction patients, whereas the soluble E-selectin levels were similar between acute myocardial infarction patients and control subjects. Our results suggest that migration inhibitory factor may play a role in the atherosclerotic process. .

The impact of previous para-areolar incision in the upper outer quadrant of the breast on the localization of the sentinel lymph node in a canine model

OBJECTIVES: This paper discusses the influence of a para-areolar incision in the upper outer quadrant of the breast on the location of the sentinel lymph node in a canine model. METHODS: The sentinel lymph node was marked with technetium-99, which was injected into the subareolar skin of the cranial breast. After the marker had migrated to the axilla, an arcuate para-areolar incision was performed 2 cm from the nipple in the upper outer quadrant. Patent blue dye was then injected above the upper border of the incision. At the marked site, an axillary incision was made, and the sentinel lymph node was identified by gamma probe and/or by direct visualization of the dye. The agreement between the two injection sites and the two sentinel lymph node identification methods was determined. Our sample group consisted of 40 cranial breasts of 23 adult females of the species Canis familiaris. The data were analyzed by using the McNemar test and by determining the kappa agreement coefficient. RESULT: Our findings showed that in 95 percent of the breasts, the sentinel lymph node was identified by the injection of technetium-99 m into the subareolar region, and in 82 percent of the cases, the sentinel lymph node was identified by the injection of patent blue dye above the upper border of the incision. The methods agreed 82 percent of the time. CONCLUSIONS: Previous para-areolar incisions in the upper outer quadrant did not interfere significantly with the biopsy when the dye was injected above the upper border of the incision.

Condrosarcoma mesenquimal sinonasal grado tres y carcinosarcoma de glándula Mamaria de un canino: estudios clínico e histopatológico / Sinunasal mesenchymal chondrosarcoma grade 3 and mammary gland carcinosarcoma of canine: clinical and histopathology study

A la Clínica Veterinaria de la Universidad de los Llanos, llegó un canino hembra de 9 años de edad raza Chow Chow, cuyo motivo de consulta fue epistaxis bilateral 4 meses atrás y una masa en la región nasal. Según lo reportado por el propietario, la masa había comenzado a salir 1 mes atrás del día de la consulta. Al examen clínico presentaba una masa subdérmica en la región nasal superior de 2 cm de diámetro. Se realizó una citología de la misma y se encontraron células inflamatorias sin presencia de células neoplásicas. El paciente volvió al mes y la masa con un diámetro de 5cm, estaba ubicada en la región nasal superior y región zigomática. El can presentaba disnea, anorexia, deshidratación del 6 por ciento, secreción mucopurulenta nasal y ocular, midriasis bilateral, reflejo corneal bilateral negativo, aumento de la presión infraocular del ojo derecho. En la glándula mamaria inguinal derecha presentaba una masa de 2cm de diámetro dura y móvil. Se realizó una citología por aspirado con aguja fina, de distintas zonas de las masas, tanto de la nariz, como de la glándula mamaria. Se valoró la citología permitiéndose definir el origen tumoral del proceso. Se realizó biopsia por incisión de la región sinonasal, diagnosticándose tumor mesenquimal maligno grado tres condrosarcoma sinonasal, conformado por células cartilaginosas pleomórficas con anisocariosis. Se realizaron radiografías de la región nasal y del pulmón, encontrándose una zona radiopaca a nivel del seno maxilar con osteolisis del hueso, se evidenciaba la masa de aproximadamente 4 cm de ancho por 2 cm de largo en el lado derecho. En el pulmón no se evidenció metástasis. Después del diagnóstico de histopatología se decide realizar la eutanasia, encontrándose histopatológicamente metástasis en pulmón, confirmación del condrosarcoma mesenquimal y un carcinosarcoma de glándula mamaria.

To the Veterinary Clinic of the Universidad de los Llanos, come a 9 years old Chow Chow female canine, whose consultation reason was a bilateral epistaxis occurred 4 months ago, sudden loss of the vision and a mass in the nasal region of 2cm of diameter approximately, according to the report of the owner, the mass showed up 1 month the day of the consultation. To the clinical exam they were the following abnormal discoveries. Hirsute hair, opaque, presented a subdermic mass approximately in the nasal region superior of 2 cm. diameter that grew to 5 cm. diameter after 1 month of the consultation, located in the nasal region superior and zigomatic region, of hard consistency, the animal had dysnea, bilateral mydriasis, the bilateral corneal reflection was negative, increase of the infraocular pressure of the right eye, the realized test of obstacles in the clinic was negative, that which showed us a blindness. Besides a complete clinical exploration and taking of the advantages of the cytology, she was carried out an aspired with fine needle of different areas of the masses so much neoplastic of the nose and of the region of the mammary gland, being obtained two types of samples. The cytology was evaluated to define origin of the tumors of the process. She was carried out biopsy for incision of the sinunosal region being diagnosed wicked tumor mesenchymal Chondrosarcoma sinunasal that commits bone. After having carried out the autopsy they took samples for histopathology. Being diagnosed mesenchymal chondrosarcoma sinunasal grade 3, with metastasis to lung, and a carcinosarcoma of mammary gland.

Assessment of cell proliferation and prognostic factors in canine mammary gland tumors / Avaliação da proliferação celular e fatores prognósticos em tumores mamários caninos

Three methods for the analysis of cell proliferation, mitotic index/10 high-power fields (10 HPF), mitotic index/four sets of 10 HPF (40 HPF), and MIB-1 index were evaluated in a series of canine mammary gland tumors, as well as the possible correlation between them. Fifty-six canine mammary gland tumors, including 23 benign and 33 malignant, were studied. In addition, the prognostic impact of mitotic index/10 HPF, and histological malignancy grade were evaluated in 17 malignant tumors, being seven ductal and 10 metaplastic carcinomas. The three methods used to evaluate cell proliferation were correlated with the prognostic impact of mitotic index/10 HPF and histological malignancy grade. The results showed a strong association between mitotic figure counts and MIB-1 index (P<0.0001). A correlation was observed between mitotic count per 40 HPF and MIB-1, and between mitotic index per 10 HPF and 40 HPF (P<0.05). Moreover, histological malignancy grade and mitotic figure counts were excellent prognostic factors during three-year follow-up (P<0.05). There was a correlation between the three methods used for the evaluation of cell proliferation and prognostic factors as observed in human breast cancer studies.

Avaliaram-se três métodos de proliferação celular, índice mitótico/10 campos de grande aumento (10 CGA), quatro vezes 10 CGA (40 CGA) e índice de marcação por MIB-1, em uma série de tumores mamários caninos, e as possíveis correlações entre estes métodos. Foram estudados 56 tumores mamários caninos, 23 benignos e 33 malignos. Foi também avaliado o impacto prognóstico do índice mitótico (10 CGA) e o grau histológico maligno em 17 tumores malignos, sete carcinomas ductais e 10 carcinomas metaplásicos. A correlação entre os três métodos para avaliar a proliferação celular e o impacto prognóstico do índice mitótico por 10 CGA e o grau histológico maligno foi realizada. Os resultados mostraram que existe uma forte associação entre contagem de mitose e o índice de marcação por MIB-1(P<0,0001) e correlação entre contagem de mitoses em 40 CGA e índice de marcação por MIB-1 e entre índice mitótico em 10 CGA e 40 CGA (P<0,05). Observou-se correlação entre os três métodos de avaliação da proliferação celular e os fatores prognósticos semelhante aos estudos de câncer de mama humano.

Qualidade diagnóstica da biópsia com agulha Super-core II® de nódulos mamários de cadelas / Diagnostic quality of mammary nodes biopsy with Super-core II® needle of bitches

A biópsia com agulha de corte é um método fácil e rápido para obtenção de um fragmento do tumor, e amplamente utilizado no diagnóstico de lesões mamárias em mulheres. O objetivo do estudo foi realizar a avaliação diagnóstica da biópsia em 26 nódulos mamários de 19 cadelas, utilizando a agulha de corte Super-core II® 14-ga x 9cm. Após a biópsia, os pacientes foram submetidos à mastectomia para obtenção dos nódulos mamários. As amostras da biópsia e os nódulos foram analisados histopatologicamente e as neoplasias foram classificadas segundo a Organização Mundial de Saúde (OMS). A biópsia com agulha mostrou sensibilidade de 100 por cento e especificidade de 71,4 por cento no diagnóstico de adenocarcinomas, e no diagnóstico de carcinossarcomas mostrou 71,4 por cento de sensibilidade e 100 por cento de especificidade. Além disso, segundo o teste de Goodman e Kruskall (P<0,0001), a biópisa com agulha apresentou eficácia diagnóstica de 81,6 por cento. Conclui-se que a biópsia com Super-core II® é um método eficaz na classificação histológica de neoplasias mamárias em cadelas.

The core needle biopsy is an easy method and fast that offers tumors sample, widely used in diagnosis of mammary injuries in women. The aim of the study was the diagnostic evaluation of the biopsy in 26 mammary nodes of 19 female dogs, using the cut needle Super-core II® 14-ga x 9cm. After the biopsy, the patients had been submitted to mastectomy for attainment of mammary nodes. The biopsies specimens and the nodes had been histological analyzed and classified neoplasm according to World Health Organization (WHO). The core needle biopsy showed sensitivity of 100 percent and specificity of 71.4 percent in the diagnosis of adenocarcinomas and in the diagnosis of carcinosarcomas, the 71.4 percent of sensitivity and 100 percent of specificity. And according to Goodman and Kruskall (P<0.0001) test presented diagnostic effectiveness of 81.6 percent. The biopsy with Super-core II is an efficient method for the histological classification of mammary nodes in female dogs.

DNA flow cytometry of canine mammary tumors: comparative aspects with human breast tumors

Flow cytometric analysis of DNA content was performed on 28 samples of canine mammary tumors. Nine of them were benign and 19 were malignant. All benign tumors and 11 malignant tumors (57.9 percent) were diploid (P<0.05). Form the aneuploid tumors, five (26.3 percent) were hyperdiploid, one (5.3 percent) hypodiploid, one (5.3 percent) near triploid and one (5.3 percent) multiploid. The analysis of the expression of the markers PR and CD31 revealed a significant difference between diploid and aneuploid tumors (P<0.05). The immunoreactivity of PR was higher in diploid tumors, while the immunoreactivity of CD31 was stronger in aneuploid tumors. No difference between the markers MIB-1, c-erbB2, p53 and Cyclin D1 was observed (P>0.05). Using the flow cytometry analysis and immunohistochemistry, it was found a close relationship between aneuploidy and malignant character of neoplasias, progesterone receptor (PR) negative immunostaining and higher microvases density. No correlation between DNA content and S phase or immunoreactivity for the markers MIB-1, p53, c-erbB2 and Cyclin D1 was observed

Análise por citometria de fluxo de DNA foi realizada em 28 amostras de tumores mamários de cadela. Nove eram benignos e 19 malignos, sendo todos os benignos e 11 malignos (57,9 por cento) diplóides (P<0,05). Dos tumores aneuploides, cinco (26,3 por cento) eram hiperdiploides, um (5,3 por cento) hipodiploide, um (5,3 por cento) triploide e um (5,3 por cento) multiploide. A análise dos marcadores de expressão PR e CD31 revelaram significativa diferença entre tumores diploides e aneuploides (P<0,05). A imunorreatividade do PR foi maior em tumores diplóides e a imunoreatividade do CD 31 maior em tumores aneuploides. Para os marcadores MIB-1, c-erbB-2, p53 e Ciclina D1 não foi observada diferença significativa (P>0,05). Pela citometria de fluxo e pela imunoistoquímica verificaram-se uma relação entre aneuploidia e características malignas das neoplasias, receptor de progesterona imunoreação negativa e alta densidade de microvascular. Não foi observada correlação entre conteúdo de DNA e a fase S ou imunorreatividade para os marcadores MIB-1, c-erbB-2, p53 e Ciclina D1

Mammary fibroadenoma in a lamb

A fibroadenoma was diagnosed in the left udder of a 3-month-old female Chios lamb. No recurrence was observed after surgery. Grossly, the tumor had a whitishgray lobular appearance, and the lobules were interlaced with thin septa. Microscopically, the tumor was composed of proliferating fibroepithelial tissue, including differentiated ducts lined by whorls and interlacing bundles of abundant loose fibrovascular stroma. Immunohistochemistry revealed the ductal epithelium to be positive for pancytokeratin (AE1/AE3) and loose fibrovascular stroma was positive for vimentin and basal cells covering the ductal epithelium of alpha-smooth-muscle actin. Immunostaining for the estrogen and progesterone receptors was negative. A diagnosis of mammary fibroadenoma was made based on the histological and immunohistochemical findings.

c-erbB-2 expression and nuclear pleomorphism in canine mammary tumors

The objective of the present investigation was to study the expression of c-erbB-2 and MIB-1 and try to associate them with morphological features of the cell such as nuclear pleomorphism, mitotic count and histological grade in a series of 70 canine mammary gland tumors, 22 of them benign and 48 malignant. Tumors were collected at the Veterinary Hospital of UFMG (Brazil) and the Veterinary Faculty of Porto University (Portugal). c-erbB-2 expression was determined according to the guidelines provided by the manufacturer of the HercepTest system and nuclear pleomorphism, mitotic count and histological grade according the Elston and Ellis grading system. The HercepTest is the FDA-approved in vitro diagnostic test marketed by Dako. It is a semi-quantitative immunohistochemical assay used to determine overexpression of HER2 protein (human epidermal growth factor receptor) in breast cancer tissue. MIB-1 expression was also evaluated in 28 malignant tumors. Seventeen (35.4 percent) of the malignant tumors were positive for c-erbB-2 expression, which was positively associated with nuclear pleomorphism (P < 0.0001), histological grade (P = 0.0017) and mitotic count (P < 0.05). Nuclear pleomorphism also showed a positive association with MIB-1 index (P < 0.0001). These results suggest that some of the biological and morphological characteristics of the tumor are associated in canine mammary gland tumors, as also reported for human breast cancer. It was also possible to show that the immunoexpression of c-erbB-2 can be a factor in mammary carcinogenesis. This fact opens the possibility of using anti-c-erbB-2 antibodies in the treatment of canine mammary tumors.

Inmunorregulacion del crescimiento de tumores mamarios murinos / Immunoregulation of murine mammary tumor growth

Durante el crecimiento de los tumores el papel del sistema inmune es controvertido, y a pesar de las grandes expectativas en poder estimularlo para que fuera eficiente en el rechazo de los mismos, este objetivo aún no se ha cumplido. En este revisión se resumen y se analizan los estudios inmunológicos realizados con modelos de tumores murinos en nuestro laboratorio. Nosotros hemos trabajado con tumores de mama murinos, y en nuestros primeros estudios hemos determinado que el sistema inmune de los portadores de tumor durante las primeras etapas de su evolución reconoce en forma específica los antígenos tumorales, y que sus linfocitos están activados para respuestas de hipersensibilidad retardada in vivo e in vitro y angiogénesis linfocitaria. Sin embargo, esta funcionalidad no se correlaciona con los mecanismos efectores de rechazo tumoral. El reconocimiento y activación linfocitarias desaparecem a medida que tumor crece. Las células tumorales y linfocitos del portador de tumor secretan factores solubles que exacerban el crecimiento tumoral y metastásico. Las poblaciones de neutrófilos y mastocitos también se encuentran alteradas durante el crecimiento del tumor. Postulamos que las células tumorales secretan factores que inducen poblaciones celulares a producir inmunosupresores que favorecem el desarrollo del mismo tumor.