Concomitant occurrence of multicentric hemangiosarcoma and histiocytic sarcoma in a dog

Histiocytic sarcoma (HS) is uncommon malignant neoplasia of round cells with marked predilection in Rottweiler and Bernese Mountain. The disseminated form, which mainly affects the spleen, lungs, lymph nodes, bone marrow, skin, and subcutis, presents a quick and aggressive clinical behavior. Hemangiosarcoma (HAS) is a malignant neoplasm of endothelial vessel cells commonly reported to affect the right atrium of dogs' hearts. A male Rottweiler, five years old, presented flaccid paraplegia and progressive muscular atrophy in the temporal, masseter, and limbs muscles; Due to the clinical stage of the animal, euthanasia was conducted. During the necroscopic examination, it was noticed that several masses presented different sizes; some were whitish, and others were reddish and spread in multiple organs (lungs, heart, spleen, stomach, kidneys, brain, medulla, skeletal muscle, and pre-scapular lymph node). Microscopically, in some organs such as the stomach, right ventricle, lungs, and medulla, it was noticed a proliferation of myeloid cells, highly cellular, with poor demarcation, no encapsulation, and with the infiltrative growth pattern of cells with high pleomorphism. Numerous tumoral emboli were observed in the spleen, brain, skeletal muscle, and lymph node. These cells were submitted for immunohistochemistry and were positive for CD18 (HS antibody). In the right atrium, liver, and kidney it was observed malignant and infiltrative endothelial proliferation (HSA) and emboli in the medulla. Therefore, we conclude that both neoplasms (HS and HSA) cause the animal's paraplegia due to their embolism and metastasis to the spinal cord and skeletal muscle.(AU)

Plasmocitoma extramedular em cão positivo para leishmaniose: Relato de caso / Extramedullary plasmacytoma in a dog positive for leishmaniasis: case report

Os plasmocitomas extramedulares são uma proliferação excessiva de células plasmocíticas, que pode acometer nos cães, o sistema cutâneo e mucocutâneo. Classificados como benignos, já que por sua vez possuem um baixo potencial metastático, porém o local onde se infiltra se comporta de forma agressiva. A formação dos nódulos é isolada, mas podem ser múltiplos, apresentam coloração avermelhada e possuem tamanhos médios de 1 a 2 cm. O histopatológico evidencia plasmócitos, em arranjo de cordão e entremeados a uma discreta quantidade de tecido conjuntivo. O objetivo deste relato é identificar e diagnosticar um caso de plasmocitoma extramedular em cão positivo para leishmaniose.(AU)

The extramedullary plasmacytomas are an excessive proliferation of plasmacytic cells, which can affect the cutaneous and mucocutaneous systems in dogs. Classified as benign, as they in turn have a low metastatic potential, but the site where they infiltrate behaves aggressively. The formation of nodules is isolated, but they can be multiple, present with a reddish color and have average sizes of 1 to 2 cm. Histopathology shows plasma cells, in a cord arrangement and intermingled with a small amount of connective tissue. The purpose of this report is to identify and diagnose a case of oral plasmacytoma in a dog.(AU)

Tumor venéreo transmissível canino em laringe com metástase pulmonar / Canine transmissible venereal tumor in the larynx with pulmonary metastasis

Background: Canine transmissible venereal tumor (TVT) is one of the most common canine neoplasms in Brazil. Lesions develop mainly in the genital tissue and less frequently in other areas, in the extragenital form. Metastasis is rare, and the disease progression depends on the patient’s immune status. The treatment of choice is chemotherapy with vincristine sulfate, considered an effective and safe modality. The present work describes the first case of extragenital TVT in the larynx with pulmonary metastasis at the time of diagnosis. Case: An approximately 4-month-old mixed-breed bitch was attended manifesting acute clinical respiratory signs. The patient had been rescued from the street 2 months beforehand. Physical examination revealed pale mucous membranes and crackling pulmonary auscultation. Thoracic radiography was performed in 3 projections, showing multiple nodules in the lung parenchyma, followed by cytopathological examination using fine needle puncture guided by thoracic ultrasound, confirming the diagnosis of TVT. Considering the cytological finding and the absence of primary tumor lesions in the genital, oral, cutaneous or nasal regions, endoscopy was performed in order to locate a possible primary focus. The exam revealed a small erythematous tumor with smooth and regular surface, measuring approximately 2.5 cm, located in the larynx, between the arytenoid cartilages. Chemotherapy was performed with vincristine sulfate with radiographic follow-up throughout the treatment. Full remission of the pulmonary and laryngeal nodules was achieved at the end of the protocol. The animal remained in complete remission for a period of 2 years. Discussion: TVT is more frequently observed in animals of active reproductive age, and rarely in animals under 1 year of age, as in the case...

Peripheral T-cell lymphoma in the oral cavity of a cow

Background: Squamous cell carcinomas and lymphomas are the most prevalent neoplasms in cattle, the latter usually being attributed to infection by bovine leukemia virus (BLV). Neoplasms of the oral cavity are sporadic in cattle, with but asingle case of lymphoma involving this anatomic site in a bovine reported to date. This paper reports a case of lymphomainvolving the oral cavity of a dairy cow. The clinical and pathological aspects of the tumor are described and discussed.Case: A 39-month-old Holstein-Friesian cow was presented with weight loss and a tumorous growth in the left masseterregion, tearing in the left eye, and mild ipsilateral exophthalmos. Treatment with antibiotics was unsuccessful. The tumorgrowth was 16 x 11 cm, with a soft center and firm periphery, multilobulated, with white intercalated with black and friableareas from which a fetid odor emanated. The cut surface was predominantly white-yellow. A cross-section of the head,caudal to the second molar, revealed a mass infiltrating and almost completely obliterating the left nasal cavity, destroyingthe frontal sinus, the ventral conchae, and the middle and ventral meatus, and compressing the common meatus. The tracheobronchial, mediastinal, and internal iliac lymph nodes were enlarged and masses with similar characteristics to thosein the oral cavity replace their parenchyma. Microscopically, the mass consisted of large neoplastic lymphocytes arrangedin a non-encapsulated and infiltrative mantle and supported by scarce fibrovascular tissue. The cytoplasm of neoplasticcells was scarce and had distinct boundaries; the nuclei were round or oval, the chromatin was finely granulated, and theprominent nucleolus had occasionally multiplied. Nuclear pleomorphism was marked and there were, on average, five mitotic figures per microscopic field of 400x. Similar neoplastic cells obliterated the normal...

Peripheral T-cell lymphoma in the oral cavity of a cow

Background: Squamous cell carcinomas and lymphomas are the most prevalent neoplasms in cattle, the latter usually being attributed to infection by bovine leukemia virus (BLV). Neoplasms of the oral cavity are sporadic in cattle, with but asingle case of lymphoma involving this anatomic site in a bovine reported to date. This paper reports a case of lymphomainvolving the oral cavity of a dairy cow. The clinical and pathological aspects of the tumor are described and discussed.Case: A 39-month-old Holstein-Friesian cow was presented with weight loss and a tumorous growth in the left masseterregion, tearing in the left eye, and mild ipsilateral exophthalmos. Treatment with antibiotics was unsuccessful. The tumorgrowth was 16 x 11 cm, with a soft center and firm periphery, multilobulated, with white intercalated with black and friableareas from which a fetid odor emanated. The cut surface was predominantly white-yellow. A cross-section of the head,caudal to the second molar, revealed a mass infiltrating and almost completely obliterating the left nasal cavity, destroyingthe frontal sinus, the ventral conchae, and the middle and ventral meatus, and compressing the common meatus. The tracheobronchial, mediastinal, and internal iliac lymph nodes were enlarged and masses with similar characteristics to thosein the oral cavity replace their parenchyma. Microscopically, the mass consisted of large neoplastic lymphocytes arrangedin a non-encapsulated and infiltrative mantle and supported by scarce fibrovascular tissue. The cytoplasm of neoplasticcells was scarce and had distinct boundaries; the nuclei were round or oval, the chromatin was finely granulated, and theprominent nucleolus had occasionally multiplied. Nuclear pleomorphism was marked and there were, on average, five mitotic figures per microscopic field of 400x. Similar neoplastic cells obliterated the normal...(AU)

Three cases of exclusively extragenital canine transmissible Venereal Tumor (cTVT)

Background: Canine Transmissible Venereal Tumor (cTVT) is a neoplasia that affects mainly the genital organs of dogs, but can rich extragenital sites as well. It´s a tumor characterized microscopically by the presence of vacuolized round cells. Transmission occurs by implantation of these cells in non-affected tissues and the treatment is based on vincristine chemotherapy.Cases: Case 1. A 5-year-old intact male Poodle, presenting an increase volume of nasal plane came for veterinary care at a private veterinary clinic. The animal had bilateral bloody nasal secretion and dyspnea. The external genitalia had no alterations. The cytological evaluation confirmed cTVT. Treatment with vincristine sulfate weekly showed a rapid response with improvement of the respiratory condition, total remission of the mass and absence of neoplastic cells in cytology. Case 2. A 5-year-old mixed-breed canine bitch, weighing 6.7 kg, was brought to the State University of Santa Cruz Veterinary Hospital (UESC-VH), showing an increase volume in the nasal plan region, with complaints about sneezing, nasal bleeding, respiratory distress with approximately 4 months of evolution. The owner informed that the mother of these female dog, that lived in the same environment, died a month before the beginning of clinical signs of the bitch of this case, and showed a reddish vaginal mass with intense bleeding. Intranasal exfoliative cytology showed moderately cellular sample compatible with cTVT. The treatment with vincristine sulphate for 6 weeks, showed completely remission of all clinical signs. Case 3. A 3-year-old mixed-breed male dog was brought to the UESC-VH with a reddish, friable mass located in the left eye. The citology confirmed the clinical suspicion of cTVT. After six weekly sessions of chemotherapy with vincristine sulfate, the tumor regressed and a new cytological evaluation was performed, without visible of tumor cells.[...]

Three cases of exclusively extragenital canine transmissible Venereal Tumor (cTVT)

Background: Canine Transmissible Venereal Tumor (cTVT) is a neoplasia that affects mainly the genital organs of dogs, but can rich extragenital sites as well. It´s a tumor characterized microscopically by the presence of vacuolized round cells. Transmission occurs by implantation of these cells in non-affected tissues and the treatment is based on vincristine chemotherapy.Cases: Case 1. A 5-year-old intact male Poodle, presenting an increase volume of nasal plane came for veterinary care at a private veterinary clinic. The animal had bilateral bloody nasal secretion and dyspnea. The external genitalia had no alterations. The cytological evaluation confirmed cTVT. Treatment with vincristine sulfate weekly showed a rapid response with improvement of the respiratory condition, total remission of the mass and absence of neoplastic cells in cytology. Case 2. A 5-year-old mixed-breed canine bitch, weighing 6.7 kg, was brought to the State University of Santa Cruz Veterinary Hospital (UESC-VH), showing an increase volume in the nasal plan region, with complaints about sneezing, nasal bleeding, respiratory distress with approximately 4 months of evolution. The owner informed that the mother of these female dog, that lived in the same environment, died a month before the beginning of clinical signs of the bitch of this case, and showed a reddish vaginal mass with intense bleeding. Intranasal exfoliative cytology showed moderately cellular sample compatible with cTVT. The treatment with vincristine sulphate for 6 weeks, showed completely remission of all clinical signs. Case 3. A 3-year-old mixed-breed male dog was brought to the UESC-VH with a reddish, friable mass located in the left eye. The citology confirmed the clinical suspicion of cTVT. After six weekly sessions of chemotherapy with vincristine sulfate, the tumor regressed and a new cytological evaluation was performed, without visible of tumor cells.[...](AU)

Aspectos clínicos do tumor venéreo transmissível canino (Tvtc) linfóide, plasmocitóide e misto / Clinical aspects of lymphoid, plasmocytoid and mixed canine transmissible venereal tumor (TVTc)

The objective of this study was to describe the clinical aspects of the subtypes of Canine Transmissible Venereal Tumor (TVTc). The clinical record of 40 dogs with the cytologic diagnosis of TVTc was evaluated. Of these was selected information about classfication, clinical complaint and affected organs with their specific locations. In this study, the plasmocytoid TVTc prevailed. The predominant clinical complaint was penile bleeding (14/40) and vaginal bleeding (13/40). As to the location, genital (G) (34/40) and extragenital (EG) (17/40) tumors were observed, with TVTcL (G-66,66% and EG-66,66%), TVTcM (G-90% and EG-30%) and TVTcP (G-90,47% and EG-38,08%). Among the genitals, the base, body and gland prevailed, and in the vagina: ventral and dorsal floors. In the extragenital tumors, there were changes in the skin, mouth, subcutaneous, nasal region and eye. It was concluded that the TVTcP prevailed more in the skin, while the TVTcL in the head region.

Aspectos clínicos do tumor venéreo transmissível canino (Tvtc) linfóide, plasmocitóide e misto / Clinical aspects of lymphoid, plasmocytoid and mixed canine transmissible venereal tumor (TVTc)

The objective of this study was to describe the clinical aspects of the subtypes of Canine Transmissible Venereal Tumor (TVTc). The clinical record of 40 dogs with the cytologic diagnosis of TVTc was evaluated. Of these was selected information about classfication, clinical complaint and affected organs with their specific locations. In this study, the plasmocytoid TVTc prevailed. The predominant clinical complaint was penile bleeding (14/40) and vaginal bleeding (13/40). As to the location, genital (G) (34/40) and extragenital (EG) (17/40) tumors were observed, with TVTcL (G-66,66% and EG-66,66%), TVTcM (G-90% and EG-30%) and TVTcP (G-90,47% and EG-38,08%). Among the genitals, the base, body and gland prevailed, and in the vagina: ventral and dorsal floors. In the extragenital tumors, there were changes in the skin, mouth, subcutaneous, nasal region and eye. It was concluded that the TVTcP prevailed more in the skin, while the TVTcL in the head region.(AU)

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%).

Hemócitos de Bradybaena similaris e Megalobulimus abbreviatus (Gastropoda, Stylommatophora) / Hemocytes of Bradybaena similaris and Megalobulimus abbreviatus (Gastropoda, Stylommatophora)

Hemocytes act in the defense system against invading organisms, foreign particles aiding the recognition of what is own to the body of gastropods and what is not. Information and studies on the hemocytes in species of mollusks healthy (no infections), especially in Bradybaena similaris (Fèrussac, 1821) and Megalobulimus abbreviatus (Bequaert, 1948) are scarce. Therefore, this work aims at characterization and quantification of hemocytes present in the hemolymph of these two species. In this work three cell types were identified in the hemolymph of both species: round cells, hyalinocytes and granulocytes. The three types of hemocytes were measured, and the average of total diameter and the nucleus for each was calculated. On B. similaris, the average diameter of round cells was 10.7 µm, of hyalinocytes was 20 µm and of granulocytes was 25.4 µm. On M. abbreviatus, the average diameter of round cells was 11.7 µm, of hyalinocytes was 21.5 µm and of granulocytes was 30.5 µm. Although the hyalinocytes have similar averages between B. similaris and M. abbreviatus, the cells were demonstrated significant differences in their total diameter and size of the nucleus (p<0.0001). The average density of cells per ml without distinction of cellular type was 197,813 cells/ml for M. abbreviatus, and 416,333 cells/ml for B. similaris. The most frequent hemocytes in M. abbreviatus and B. similaris were hyalinocytes, unlike other gastropods.(AU)

Os hemócitos atuam no sistema de defesa contra organismos invasores e partículas estranhas, auxiliando o reconhecimento do que é próprio do corpo dos grastrópodes e o que não é. São escassas as informações e estudos sobre os hemócitos em espécies de moluscos saudáveis (sem infecções), principalmente em Bradybaena similaris (Fèrussac, 1821) and Megalobulimus abbreviatus (Bequaert, 1948). Portanto, este trabalho tem como objetivos a caracterização e quantificação dos hemócitos presentes na hemolinfa destas duas espécies. Neste trabalho, foram identificados três tipos celulares na hemolinfa de ambas espécies: as células redondas, hialinócitos e granulócitos. Os três tipos de hemócitos foram medidos e foi calculada a média do diâmetro total e do núcleo para cada um deles. Para B. similaris, o diâmetro médio das células redondas foi de 10,7 µm, dos hialinócitos foi de 20 µm e dos granulócitos de 25,4 µm. Para M. abbreviatus, o diâmetro médio foi de 11,7 µm para as células redondas, de 21,5 µm para os hialinócitos e de 30,5 µm para os granulócitos. Embora os hialinócitos possuam médias parecidas entre B. similaris e M. abbreviatus, foram detectadas diferenças significativas do diâmetro celular total e diâmetro do núcleo (p<0,0001) dessas células entre as espécies estudadas. A densidade média de células por ml, sem distinção de tipo celular foi de 197.813 células/ml para M. abbreviatus, e de 416.333 células/ml para B. similaris. Diferentemente de outros gastrópodes, os hemócitos mais frequentes em M. abbreviatus e em B. similaris foram os hialinócitos.(AU)

Hemócitos de Bradybaena similaris e Megalobulimus abbreviatus (Gastropoda, Stylommatophora) / Hemocytes of Bradybaena similaris and Megalobulimus abbreviatus (Gastropoda, Stylommatophora)

Hemocytes act in the defense system against invading organisms, foreign particles aiding the recognition of what is own to the body of gastropods and what is not. Information and studies on the hemocytes in species of mollusks healthy (no infections), especially in Bradybaena similaris (Fèrussac, 1821) and Megalobulimus abbreviatus (Bequaert, 1948) are scarce. Therefore, this work aims at characterization and quantification of hemocytes present in the hemolymph of these two species. In this work three cell types were identified in the hemolymph of both species: round cells, hyalinocytes and granulocytes. The three types of hemocytes were measured, and the average of total diameter and the nucleus for each was calculated. On B. similaris, the average diameter of round cells was 10.7 µm, of hyalinocytes was 20 µm and of granulocytes was 25.4 µm. On M. abbreviatus, the average diameter of round cells was 11.7 µm, of hyalinocytes was 21.5 µm and of granulocytes was 30.5 µm. Although the hyalinocytes have similar averages between B. similaris and M. abbreviatus, the cells were demonstrated significant differences in their total diameter and size of the nucleus (p<0.0001). The average density of cells per ml without distinction of cellular type was 197,813 cells/ml for M. abbreviatus, and 416,333 cells/ml for B. similaris. The most frequent hemocytes in M. abbreviatus and B. similaris were hyalinocytes, unlike other gastropods.

Os hemócitos atuam no sistema de defesa contra organismos invasores e partículas estranhas, auxiliando o reconhecimento do que é próprio do corpo dos grastrópodes e o que não é. São escassas as informações e estudos sobre os hemócitos em espécies de moluscos saudáveis (sem infecções), principalmente em Bradybaena similaris (Fèrussac, 1821) and Megalobulimus abbreviatus (Bequaert, 1948). Portanto, este trabalho tem como objetivos a caracterização e quantificação dos hemócitos presentes na hemolinfa destas duas espécies. Neste trabalho, foram identificados três tipos celulares na hemolinfa de ambas espécies: as células redondas, hialinócitos e granulócitos. Os três tipos de hemócitos foram medidos e foi calculada a média do diâmetro total e do núcleo para cada um deles. Para B. similaris, o diâmetro médio das células redondas foi de 10,7 µm, dos hialinócitos foi de 20 µm e dos granulócitos de 25,4 µm. Para M. abbreviatus, o diâmetro médio foi de 11,7 µm para as células redondas, de 21,5 µm para os hialinócitos e de 30,5 µm para os granulócitos. Embora os hialinócitos possuam médias parecidas entre B. similaris e M. abbreviatus, foram detectadas diferenças significativas do diâmetro celular total e diâmetro do núcleo (p<0,0001) dessas células entre as espécies estudadas. A densidade média de células por ml, sem distinção de tipo celular foi de 197.813 células/ml para M. abbreviatus, e de 416.333 células/ml para B. similaris. Diferentemente de outros gastrópodes, os hemócitos mais frequentes em M. abbreviatus e em B. similaris foram os hialinócitos.

Histomorphological and immunohistochemical characterization of 172 cutaneous round cell tumours in dogs / Caracterização histomorfológica e imuno-histoquímica de 172 neoplasias cutâneas de células redondas em cães

This paper describes the use of a panel of antibodies (CD117, CD3, CD79a, CD45, cytokeratin, vimentin and E-cadherin) on formalin-fixed, paraffin-embedded sections of canine cutaneous round cell tumours. Neoplastic tumours were diagnosed by histology and histochemical stains and included 107 mast cell tumours, 31 cutaneous histiocytomas, two localized histiocytic sarcomas, 21 cutaneous lymphomas, three plasma cell tumours, one transmissible venereal tumour and seven unclassified round cell tumours. The histologic diagnosis was modified in 39.5% of the total 172 neoplasms. The staining for CD45 and Ecadherin were variable, and therefore, the final diagnoses of cutaneous histiocytoma and localized histiocytic sarcoma were made based on histology in association with negative results for CD3, CD79a, CD117 and cytokeratin. The cellular origin of unclassified round cell tumours was defined in all cases. Cutaneous B-cell lymphoma and plasma cell tumours were CD79a-positive and could be distinguished from each other by the morphological characteristics. Mast cell tumours and T cell lymphoma were CD117 and CD3 positive, respectively. The positive staining for vimentin and the negative staining for CD3, CD79a, CD117 and cytokeratin favoured the diagnosis of transmissible venereal tumours. Thus, the final diagnosis of cutaneous round cell tumours should be based on the interpretation of immunohistochemical results together with the cellular morphology observed by histology. Therefore, more studies to optimize the specific markers in formalin-fixed, paraffinembedded tissues (especially for histiocytes) are required for definitive diagnosis of round cell tumours in dogs.(AU)

Este trabalho descreve o uso de um painel de anticorpos (CD117, CD3, CD79a, CD45, citoqueratina, vimentina e e-caderina em tecidos formalizados e parafinizados para o diagnóstico de neoplasias de células redondas em cães. Os tumores foram diagnosticados usando-se a histopatologia e a marcação imuno-histoquímica. Foram incluídos 107 mastocitomas, 31 histiocitomas cutâneos, 2 sarcomas histiocíticos localizados, 21 linfomas cutâneos, 3 plasmocitomas, 1 tumor venéreo transmissível e 7 tumores de células redondas não classificados. O diagnóstico histológico foi modificado em 39,5% do total de 172 neoplasias. A marcação do anticorpo CD45 e E-caderina foi variável e, nesse sentido, o diagnóstico final de histiocitoma cutâneo e sarcoma histiocítico localizado foi baseado na histologia em associação com os resultados negativos para CD3, CD79a, CD117 e citoqueratina. A origem celular dos tumores de células redondas não classificados foi definida em todos os casos. Linfoma cutâneo de célula B e plasmocitoma foram positivos para CD79a e foram distinguidos entre si pelas características morfológicas. Marcação positiva para vimentina e negativa para CD3, CD79a, CD117 e citoqueratina favoreceram o diagnóstico dos tumores venereos transmissíveis. Assim, o diagnóstico final dos tumores de células redondas foram baseados na interpretação dos resultados da imuno-histoquímica em conjunto com a avaliação das características morfológicas observadas na histologia. Finalmente, mais estudos em relação à padronização de marcadores específicos para tecidos parafinizados (especialmente para histiócitos) são necessários para o diagnóstico definitivo das neoplasias de células redondas em cães.(AU)