Schwannoma maligno em face de cão - relato de caso / Malignant schwannoma in dog face - case report

O Schwannoma trata-se de um tipo de tumor maligno da bainha dos nervos periféricos (TMBNP) incomum em pequenos animais. Não há predileção por raça e são mais comumente diagnosticados em cães de meia idade a idosos, podendo acometer diferentes regiões do corpo, entretanto, há raros relatos de acometimento em face. O presente trabalho tem por objetivo relatar um caso de TMBNP em face de um cão, macho, SRD, de 14 anos. O paciente apresentava uma formação de aproximadamente 10 cm em região facial esquerda, acometendo maxila e arco zigomático, com comprometimento também de seu globo ocular. Considerou-se a remoção cirúrgica paliativa devido a extensão da formação e seu posterior diagnóstico se deu através do exame histopatológico. Após a evolução clínica desfavorável que o paciente apresentou após o procedimento cirúrgico e devido ao prognóstico desfavorável frente ao diagnóstico de TMBNP, optou-se então pela eutanásia do paciente.

Schwannoma is a type of malignant tumor of the peripheral nerve sheath (TMBNP) uncommon in small animals. There is no predilection for breed and are most commonly diagnosed in middle-aged to elderly dogs, which may affect different regions of the body, however, there are rare reports of involvement in the face. dog, male, SRD, 14 years old. The patient had a formation of approximately 10 cm in the left facial region, affecting the maxilla and zygomatic arch, also affecting his eyeball. Consider whether the palliative surgical removal due to the extension of the formation and its subsequent diagnosis was made through histopathological examination. After the unfavorable clinical evolution that the patient presents after the surgical procedure and due to the unfavorable prognosis regarding the diagnosis of TMBNP, the patient was then euthanized.

Schwannoma maligno em face de cão - relato de caso / Malignant schwannoma in dog face - case report

O Schwannoma trata-se de um tipo de tumor maligno da bainha dos nervos periféricos (TMBNP) incomum em pequenos animais. Não há predileção por raça e são mais comumente diagnosticados em cães de meia idade a idosos, podendo acometer diferentes regiões do corpo, entretanto, há raros relatos de acometimento em face. O presente trabalho tem por objetivo relatar um caso de TMBNP em face de um cão, macho, SRD, de 14 anos. O paciente apresentava uma formação de aproximadamente 10 cm em região facial esquerda, acometendo maxila e arco zigomático, com comprometimento também de seu globo ocular. Considerou-se a remoção cirúrgica paliativa devido a extensão da formação e seu posterior diagnóstico se deu através do exame histopatológico. Após a evolução clínica desfavorável que o paciente apresentou após o procedimento cirúrgico e devido ao prognóstico desfavorável frente ao diagnóstico de TMBNP, optou-se então pela eutanásia do paciente.(AU)

Schwannoma is a type of malignant tumor of the peripheral nerve sheath (TMBNP) uncommon in small animals. There is no predilection for breed and are most commonly diagnosed in middle-aged to elderly dogs, which may affect different regions of the body, however, there are rare reports of involvement in the face. dog, male, SRD, 14 years old. The patient had a formation of approximately 10 cm in the left facial region, affecting the maxilla and zygomatic arch, also affecting his eyeball. Consider whether the palliative surgical removal due to the extension of the formation and its subsequent diagnosis was made through histopathological examination. After the unfavorable clinical evolution that the patient presents after the surgical procedure and due to the unfavorable prognosis regarding the diagnosis of TMBNP, the patient was then euthanized.(AU)

Tumor maligno da bainha de nervo periférico e osteopatia hipertrófica em cadela / Malignant peripheral nerve sheath tumor and hypertrophic osteopathy in a bitch

Background: Malignant peripheral nerve sheath tumors (MPNSTs) are rare, aggressive, relapsing, metastatic cutaneousneoplasms of mesenchymal origin. So far, no account on the association of this disease with hypertrophic osteopathy (HO)in dogs is available in the literature. Current theories on the possible causes of HO suggest that this disease may be triggered by a primary neoplasm as well as by its metastasis. The objective of this work is to report the clinical, cytological,radiographic, histopathological, and immunohistochemical aspects of a dog affected by MPNST and HO.Case: A 13-year-old female mongrel dog was presented with a history of ulcerated nodular lesion on the skin of the flank.Several ulcerated and non-ulcerated tumors were observed on the thorax, neck, and head at the physical exam. Cytological examination of the nodules revealed presence of mesenchymal cells with a malignant aspect. Complete blood countrevealed anemia. There were no alterations in the biochemical tests performed. Thoracic radiographs showed presence of anodular interstitial pattern in the cranial, medial, and caudal lobes of the lungs. To improve quality of life of the patient, theveterinary team opted for surgical excision of the tumoral ulcerations. Slight claudication in the pelvic limbs was noticedprior to the surgery. Histopathological analyses of the excised nodules verified the existence of malignant mesenchymalneoplasia, which was categorized as peripheral nerve sheath tumor after immunohistochemical examination. Additionalcutaneous tumors emerged after surgical excision, along with increased claudication, edema, and pain in the legs. Completeblood count revealed persistent anemia, lymphopenia, monocytosis, and neutrophilia. Radiographs showed an increasein the number and size of the nodules. Radiography of the limbs showed presence of palisading periosteal reaction, andincreased...

Tumor maligno da bainha de nervo periférico e osteopatia hipertrófica em cadela / Malignant peripheral nerve sheath tumor and hypertrophic osteopathy in a bitch

Background: Malignant peripheral nerve sheath tumors (MPNSTs) are rare, aggressive, relapsing, metastatic cutaneousneoplasms of mesenchymal origin. So far, no account on the association of this disease with hypertrophic osteopathy (HO)in dogs is available in the literature. Current theories on the possible causes of HO suggest that this disease may be triggered by a primary neoplasm as well as by its metastasis. The objective of this work is to report the clinical, cytological,radiographic, histopathological, and immunohistochemical aspects of a dog affected by MPNST and HO.Case: A 13-year-old female mongrel dog was presented with a history of ulcerated nodular lesion on the skin of the flank.Several ulcerated and non-ulcerated tumors were observed on the thorax, neck, and head at the physical exam. Cytological examination of the nodules revealed presence of mesenchymal cells with a malignant aspect. Complete blood countrevealed anemia. There were no alterations in the biochemical tests performed. Thoracic radiographs showed presence of anodular interstitial pattern in the cranial, medial, and caudal lobes of the lungs. To improve quality of life of the patient, theveterinary team opted for surgical excision of the tumoral ulcerations. Slight claudication in the pelvic limbs was noticedprior to the surgery. Histopathological analyses of the excised nodules verified the existence of malignant mesenchymalneoplasia, which was categorized as peripheral nerve sheath tumor after immunohistochemical examination. Additionalcutaneous tumors emerged after surgical excision, along with increased claudication, edema, and pain in the legs. Completeblood count revealed persistent anemia, lymphopenia, monocytosis, and neutrophilia. Radiographs showed an increasein the number and size of the nodules. Radiography of the limbs showed presence of palisading periosteal reaction, andincreased...(AU)

Application of a meshed skin graft in the surgical bed immediately after resection of neurofibrosarcoma in the distal limb region of a dog

Background: Malignant peripheral nerve sheath tumors are neurogenic neoplasms that originate from cells that surroundthe axons of peripheral nerves. Surgery is the treatment of choice for peripheral nerve sheath tumors. They have a betterprognosis when the lesion is in the extremity of a limb and the surgeon leaves wide peripheral margins after resection.However, this procedure makes local treatment a challenge due to difficult wound healing in this region. This report describes a successful case involving the use of a meshed skin graft immediately after resection of a neurofibrosarcoma inthe distal region of the radius bone of a dog.Case: A 6-year-old Boxer bitch weighing 40 kg was admitted with a history of a round, firm, non-ulcerated skin noduleattached to the lateral side of the distal region of the right radius bone, which had been present for about 40 days. Fineneedle aspiration cytology of the lesion showed the presence of mesenchymal cells, suggesting a sarcoma. Thus, the decision was made for an incisional biopsy to confirm the diagnosis and for the preparation of a subdermal pattern tubular flapfor subsequent rotation and transposition to close the wound that would be formed after the complete removal of the lesion.After the 7th postoperative day, the diagnosis of low-grade neurofibrosarcoma was confirmed and due to the presence ofnecrotic onset in the middle portion of the tubular flap, further surgical intervention was scheduled for the resection of thetube flap, en bloc removal of the neoplastic lesion with peripheral margins of 2 cm, and wound closure with a free skingraft. A mesh skin graft was made with a portion of the right flank skin. The mesh graft was carefully implanted on therecipient bed using simple interrupted sutures with a 3-0 non-absorbable monofilament suture material. A dressing madewith water-based sterile lubricating solution and...

Application of a meshed skin graft in the surgical bed immediately after resection of neurofibrosarcoma in the distal limb region of a dog

Background: Malignant peripheral nerve sheath tumors are neurogenic neoplasms that originate from cells that surroundthe axons of peripheral nerves. Surgery is the treatment of choice for peripheral nerve sheath tumors. They have a betterprognosis when the lesion is in the extremity of a limb and the surgeon leaves wide peripheral margins after resection.However, this procedure makes local treatment a challenge due to difficult wound healing in this region. This report describes a successful case involving the use of a meshed skin graft immediately after resection of a neurofibrosarcoma inthe distal region of the radius bone of a dog.Case: A 6-year-old Boxer bitch weighing 40 kg was admitted with a history of a round, firm, non-ulcerated skin noduleattached to the lateral side of the distal region of the right radius bone, which had been present for about 40 days. Fineneedle aspiration cytology of the lesion showed the presence of mesenchymal cells, suggesting a sarcoma. Thus, the decision was made for an incisional biopsy to confirm the diagnosis and for the preparation of a subdermal pattern tubular flapfor subsequent rotation and transposition to close the wound that would be formed after the complete removal of the lesion.After the 7th postoperative day, the diagnosis of low-grade neurofibrosarcoma was confirmed and due to the presence ofnecrotic onset in the middle portion of the tubular flap, further surgical intervention was scheduled for the resection of thetube flap, en bloc removal of the neoplastic lesion with peripheral margins of 2 cm, and wound closure with a free skingraft. A mesh skin graft was made with a portion of the right flank skin. The mesh graft was carefully implanted on therecipient bed using simple interrupted sutures with a 3-0 non-absorbable monofilament suture material. A dressing madewith water-based sterile lubricating solution and...(AU)

Diferential diagnosis between esophageal granuloma and pulmonary metastasis

Background: Spirocercosis is a parasitic infection caused by Spirocerca lupi. This pathology affects canid carnivores, especially domestic dogs. Early diagnosis has been proven challenging and most infected animals are diagnosed when disease is in advanced stage. Exams such as computed tomography scans or radiographs can aid in disease confirmation. Radiographic exam frequently reveals the presence of a mass located in mediastinal region, which can be erroneously diagnosed as pulmonary mass. The aim of this study was to report the differential diagnosis between paraesophageal granuloma, possibly due to spirocercosis, and pulmonary metastasis in a dog with a history of neurofibrosarcoma.Case: A 8 year-old male Cocker Spaniel dog, weighing 17.4 kg, was presented with anterior limb suspension and a recurrent nodule of 2.0 cm diameter, located on the main pad, with previous diagnosis of neurofibrosarcoma (malignant Schwannoma). Routine evaluation work-up included thoracic radiographs and abdominal ultrasound for clinical staging, electrocardiogram, complete blood count (CBC), coagulogram, renal and hepatic function tests, with results within the normal range for the species. The dog submitted to left anterior limb amputation due to recurrent neurofibrosarcoma in the carpal region. Histopathological exam confirmed recurrent neurofibrosarcoma without vascular invasion. Considering neoplasm biological behavior and clean surgical margins, only routine follow-up was established, with clinical exams. The dogwas presented to the Veterinary Hospital five months after surgical treatment and it was presented with fever, prostration, and history of vomiting. Radiographic exam showed a circumscribed mass in caudal mediastinal area. Computed tomography scan was performed to best evaluate the mass and the result was compatible with paraesophageal abscess.[...]

Diferential diagnosis between esophageal granuloma and pulmonary metastasis

Background: Spirocercosis is a parasitic infection caused by Spirocerca lupi. This pathology affects canid carnivores, especially domestic dogs. Early diagnosis has been proven challenging and most infected animals are diagnosed when disease is in advanced stage. Exams such as computed tomography scans or radiographs can aid in disease confirmation. Radiographic exam frequently reveals the presence of a mass located in mediastinal region, which can be erroneously diagnosed as pulmonary mass. The aim of this study was to report the differential diagnosis between paraesophageal granuloma, possibly due to spirocercosis, and pulmonary metastasis in a dog with a history of neurofibrosarcoma.Case: A 8 year-old male Cocker Spaniel dog, weighing 17.4 kg, was presented with anterior limb suspension and a recurrent nodule of 2.0 cm diameter, located on the main pad, with previous diagnosis of neurofibrosarcoma (malignant Schwannoma). Routine evaluation work-up included thoracic radiographs and abdominal ultrasound for clinical staging, electrocardiogram, complete blood count (CBC), coagulogram, renal and hepatic function tests, with results within the normal range for the species. The dog submitted to left anterior limb amputation due to recurrent neurofibrosarcoma in the carpal region. Histopathological exam confirmed recurrent neurofibrosarcoma without vascular invasion. Considering neoplasm biological behavior and clean surgical margins, only routine follow-up was established, with clinical exams. The dogwas presented to the Veterinary Hospital five months after surgical treatment and it was presented with fever, prostration, and history of vomiting. Radiographic exam showed a circumscribed mass in caudal mediastinal area. Computed tomography scan was performed to best evaluate the mass and the result was compatible with paraesophageal abscess.[...](AU)

Case report and immunohistochemical study of a malignant peripheral nerve sheath tumor in a dog / Relato de caso e estudo imuno-histoquímico de tumor maligno da bainha do nervo periférico em um cão

Malignant peripheral nerve sheath tumor is rare and rarely reported in dogs. The term neurofibroma/sarcoma is classically used when the tumor is composed of Schawann and perineural cells. This work describes the clinical, histopathological, and immunohistochemical case of a subcutaneous malignant peripheral nerve sheath tumor, most likely a malignant neurofibroma located in the pelvic member of a Rottweiler dog. Histopathological features and immunohistochemical analysis corroborated the diagnosis, showing positivity for S-100 protein, vimentin, and CD57, and was useful to distinguish this type of neoplasm from other malignancies of similar morphologies.(AU)

O tumor maligno da bainha do nervo periférico é raro e pouco descrito em cães. Classicamente, o termo "neurofibroma/sarcoma" é empregado quando o tumor é composto por células de Schwann e células perineurais. Neste relato são descritos os achados clínicos, histopatológicos e imuno-histoquímicos de um caso de tumor maligno da bainha do nervo periférico, provavelmente neurofibrossarcoma, localizado no subcutâneo do membro pélvico de um cão da raça Rottweiler. Os achados histopatológicos associados às observações imuno-histoquímicas contribuíram para o diagnóstico, sendo observada positividade para proteína S-100, vimentina e CD57, permitindo a diferenciação da neoplasia em questão de outros tumores malignos com características morfológicas similares.(AU)

Case report and immunohistochemical study of a malignant peripheral nerve sheath tumor in a dog / Relato de caso e estudo imuno-histoquímico de tumor maligno da bainha do nervo periférico em um cão

Malignant peripheral nerve sheath tumor is rare and rarely reported in dogs. The term neurofibroma/sarcoma is classically used when the tumor is composed of Schawann and perineural cells. This work describes the clinical, histopathological, and immunohistochemical case of a subcutaneous malignant peripheral nerve sheath tumor, most likely a malignant neurofibroma located in the pelvic member of a Rottweiler dog. Histopathological features and immunohistochemical analysis corroborated the diagnosis, showing positivity for S-100 protein, vimentin, and CD57, and was useful to distinguish this type of neoplasm from other malignancies of similar morphologies.(AU)

O tumor maligno da bainha do nervo periférico é raro e pouco descrito em cães. Classicamente, o termo "neurofibroma/sarcoma" é empregado quando o tumor é composto por células de Schwann e células perineurais. Neste relato são descritos os achados clínicos, histopatológicos e imuno-histoquímicos de um caso de tumor maligno da bainha do nervo periférico, provavelmente neurofibrossarcoma, localizado no subcutâneo do membro pélvico de um cão da raça Rottweiler. Os achados histopatológicos associados às observações imuno-histoquímicas contribuíram para o diagnóstico, sendo observada positividade para proteína S-100, vimentina e CD57, permitindo a diferenciação da neoplasia em questão de outros tumores malignos com características morfológicas similares.(AU)

Schwannoma maligno cutâneo em canino / ienne

As neoplasias primárias de nervos periféricos apresentam-se com pouca frequência em pequenos animais, sendo de aproximadamente 0,5% a incidência de tumores neurais benignos e malignos em cães. O presente trabalho tem por objetivo relatar o caso de uma fêmea canina, sem raça definida, de grande porte e onze anos de idade, atendida no Hospital Veterinário da Universidade Federal de Mato Grosso (HOVET-UFMT), apresentando neoformação em região torácica com evolução de dez meses. O nódulo media aproximadamente cinco centímetros de diâmetro, apresentava-se aderido ao subcutâneo, de formato regular e consistência firme. Ao exame clínico, não foram observadas dor à palpação ou ulceração cutânea. Após a realização dos exames pré-cirúrgicos hematológicos e de imagem (radiografia torácica), sem alterações significativas; a paciente foi encaminhada para a exérese da neoformação. Perante avaliação histopatológica, foi observada massa circunscrita por cápsula de tecido conjuntivo e células dispostas em múltiplos padrões regulares, ocasionalmente, em redemoinhos. Proliferação de células neoplásicas com moderado pleomorfismo celular, núcleo eosinofílico redondo a ovalado, nucléolo fortemente basofílico e citoplasma abundante, por vezes alongado. Anisocariose eanisocitose evidentes, além de figuras bizarras. Observou-se também a presença de infiltrado inflamatório mononuclear multifocal. Sendo assim, o diagnóstico conclusivo foi o de tumor de bainha de nervo periférico maligno (Schwannoma maligno). O procedimento cirúrgico para a extirpação da neoplasia foi realizado respeitando amplas margens de segurança. Por este motivo, mostrou-se eficaz, pois o paciente não apresentou recidivas locais, tampouco metástases a distancia em um período de 26 meses

The primary neoplasms of peripheral nerves present with low frequency in small animals, and from about 0.5 % to neural incidence of benign and malignant tumors in dogs. Herein we report one case of a large female mongrel dog, it was eleven years old, attended at the Veterinary Hospital of the Federal University of Mato Grosso (HOVET-UFMT), with formation in the thoracic region with 10 months evolution. The nodule measuring approximately five centimeters in diameter, it was attached to the subcutaneous, regular format and firm consistency. On clinical examination, there were no pain on palpation and cutaneous ulceration. After completion of hematological pre-surgical and imaging tests (thoracic radiography), with no significant change;the patient was referred to the removal of the neoformation. Before histopathological evaluation, mass was observed circumscribed by connective tissue capsule and cells arranged in multiple regular patterns occasionally in swirls. Proliferation of neoplastic cells with moderate cellular pleomorphism, eosinophilic core round to oval,strongly basophilic nucleoli and abundant cytoplasm, sometimes elongated. It presents anisocariose and obvious anisocytosis with bizarre figures. Also noted it is the presence of multifocal mononuclear inflammatory infiltrate.Thus, the conclusive diagnosis was that of a malignant peripheral nerve sheath tumor (malignant schwannoma).The surgical procedure for removal of the tumor was carried out respecting ample safety margins. For this reason, it was effective because the patient did not present local recurrence, metastases either the distance over a period of 26 months

Schwannoma maligno cutâneo em canino / ienne

As neoplasias primárias de nervos periféricos apresentam-se com pouca frequência em pequenos animais, sendo de aproximadamente 0,5% a incidência de tumores neurais benignos e malignos em cães. O presente trabalho tem por objetivo relatar o caso de uma fêmea canina, sem raça definida, de grande porte e onze anos de idade, atendida no Hospital Veterinário da Universidade Federal de Mato Grosso (HOVET-UFMT), apresentando neoformação em região torácica com evolução de dez meses. O nódulo media aproximadamente cinco centímetros de diâmetro, apresentava-se aderido ao subcutâneo, de formato regular e consistência firme. Ao exame clínico, não foram observadas dor à palpação ou ulceração cutânea. Após a realização dos exames pré-cirúrgicos hematológicos e de imagem (radiografia torácica), sem alterações significativas; a paciente foi encaminhada para a exérese da neoformação. Perante avaliação histopatológica, foi observada massa circunscrita por cápsula de tecido conjuntivo e células dispostas em múltiplos padrões regulares, ocasionalmente, em redemoinhos. Proliferação de células neoplásicas com moderado pleomorfismo celular, núcleo eosinofílico redondo a ovalado, nucléolo fortemente basofílico e citoplasma abundante, por vezes alongado. Anisocariose eanisocitose evidentes, além de figuras bizarras. Observou-se também a presença de infiltrado inflamatório mononuclear multifocal. Sendo assim, o diagnóstico conclusivo foi o de tumor de bainha de nervo periférico maligno (Schwannoma maligno). O procedimento cirúrgico para a extirpação da neoplasia foi realizado respeitando amplas margens de segurança. Por este motivo, mostrou-se eficaz, pois o paciente não apresentou recidivas locais, tampouco metástases a distancia em um período de 26 meses(AU)

The primary neoplasms of peripheral nerves present with low frequency in small animals, and from about 0.5 % to neural incidence of benign and malignant tumors in dogs. Herein we report one case of a large female mongrel dog, it was eleven years old, attended at the Veterinary Hospital of the Federal University of Mato Grosso (HOVET-UFMT), with formation in the thoracic region with 10 months evolution. The nodule measuring approximately five centimeters in diameter, it was attached to the subcutaneous, regular format and firm consistency. On clinical examination, there were no pain on palpation and cutaneous ulceration. After completion of hematological pre-surgical and imaging tests (thoracic radiography), with no significant change;the patient was referred to the removal of the neoformation. Before histopathological evaluation, mass was observed circumscribed by connective tissue capsule and cells arranged in multiple regular patterns occasionally in swirls. Proliferation of neoplastic cells with moderate cellular pleomorphism, eosinophilic core round to oval,strongly basophilic nucleoli and abundant cytoplasm, sometimes elongated. It presents anisocariose and obvious anisocytosis with bizarre figures. Also noted it is the presence of multifocal mononuclear inflammatory infiltrate.Thus, the conclusive diagnosis was that of a malignant peripheral nerve sheath tumor (malignant schwannoma).The surgical procedure for removal of the tumor was carried out respecting ample safety margins. For this reason, it was effective because the patient did not present local recurrence, metastases either the distance over a period of 26 months(AU)

Retrospective canine skin peripheral nerve sheath tumors data with emphasis on histologic, immunohistochemical and prognostic factors / Dados retrospectivos de tumores de bainha de nervo periférico na pele de cães com ênfase a fatores histológicos, imuno-histoquímicos e prognósticos

In this retrospective study was determined the frequency of canine skin peripheral nerve sheath tumors (PNST) in cases diagnosed by the Setor de Patologia Veterinária of the Universidade Federal do Rio Grande do Sul (SPV-UFRGS), Brazil, between the years 2000 and 2012. The canine profiles, as well as histological, immunohistochemical and prognostic aspects of the tumors were based on 70 samples, comprising 40 females, 29 males and one unspecified sample. Between 2000 and 2012, 2,984 skin tumors of dogs were diagnosed in the SPV-UFRGS, totaling 2.34% of skin neoplasms in dogs. Animals that comprised the largest amount of samples (43%) were those with no breed (SRD), followed by German Shepherds (10%). Females were more affected than males (40/70 - 57% and 29/70 - 41% respectively). Skin PNST of this research showed predominant localization on the limbs (40% in the forelimbs and 29% in the hindlimbs); affecting adult dogs, mostly aged between 8 and 11 years (54%). The samples were routinely processed for hematoxylin and eosin, and were also evaluated by toluidine blue and Masson's trichrome staining, and immunohistochemistry (IHC) anti-vimentin, -S-100, -GFAP, -actin, von Willebrand factor and neurofilament. Anisocytosis and anisokaryosis, mitotic index, intratumoral necrosis, invasion of adjacent tissues, tumor location, local recurrence and metastasis were related to the diagnosis of benign (49/70) or malignant tumor (21/70). The Antoni A histological pattern was observed more frequently in benign tumors. The immunohistochemistry helped to diagnose PNST, and anti-vimentin and anti-protein S-100 showed the highest rates of immunostaining. Throughout statistical analysis of animals with tumor recurrence, it was found that the chance of an animal with a malignant peripheral nerve sheath tumor to develop recurrence is 4.61 times higher than in an animal that had a benign tumor.(AU)

Neste estudo retrospectivo foi determinada a frequência dos tumores de bainha de nervo periférico (TBNP) na pele de cães diagnosticados pelo Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul (SPV-UFRGS), Brasil, no período de 2000 a 2012. O histórico dos cães, assim como a histologia, a imuno-histoquímica e o prognóstico em relação aos tumores foram baseados em 70 amostras histológicas, correspondendo a 40 fêmeas (57%), 29 machos (41%) e uma amostra sem a informação do sexo. De 2000 a 2012, foram diagnosticados 2984 tumores de pele de cães pelo SPV-UFRGS, totalizando 2,34% das neoplasias em cães. A maior parte das amostras (43%) foi proveniente de animais sem raça definida (SRD), seguidos pelos da raça Pastor Alemão (10%). A localização predominante dos TBNP desta pesquisa ocorreu em membros (40% em membro tóracico e 29% em membro pélvico), afetando principalmente cães de oito a 11 anos idade (54%). As amostras foram processadas rotineiramente para coloração de Hematoxilina e eosina, e foram realizadas as colorações de azul de toluidina e tricrômio de Masson, assim como realizada imuno-histoquímica (IHQ) anti-vimentina, -S-100, -GFAP, -actina, von Willbrand e neurofilamento. Os fatores anisocitose e anisocariose, índice mitótico, necrose intratumoral, invasão tumoral em tecidos adjacentes, localização tumoral, local de recorrência e metástase foram relacionados com o diagnóstico de benignidade (49/70) ou malignidade (21/70). O padrão histológico de Antoni A foi observado com mais frequência em tumores benignos. A IHQ auxiliou no diagnóstico dos TBNP, com maiores índices de imunomarcação anti-vimentina e S-100. A análise estatística das amostras de animais que apresentaram recidiva tumoral evidenciou que a chance de um animal com tumor de bainha de nervo periférico maligno desenvolver recidiva é 4,61 vezes maior do que em animais que apresentam tumor benigno.(AU)

Cutaneous Schwannoma in a Cow

Schwannoma is a peripheral nerve sheath tumor (PNST), commonly found as a spindle cell tumor of autonomic nerves and rarely involving the skin of cattle. The present report describes the histopathology and immunohistochemistry features of a localized (solitary) benign PNST with final diagnosis of cutaneous schwannoma in a 4-year-old female Holstein bovine. The dome-shaped, well circumscribed, firm, non-smooth surfaced mass was composed of spindle-shaped cells arranged predominantly in interlacing fascicles or streams with a moderate to strong intervening collagenous stroma. Histopathologic changes included typical hypocellular areas with pale scant eosinophilic cytoplasm (Antoni B pattern) similar to myxomatous tissue, and hypercellular areas with deeply eosinophilic cytoplasm (non-typical Antoni A pattern) without nuclear palisading or Verocay bodies formation. Immunohistochemical reactions for S-100 protein, a Schwann cell marker, and vimentin were strong in the neoplastic cells. Other markers as desmin, neuron specific enolase (NSE), CD34, and p53 were all negative. It was concluded that concurrent evaluation of both histological and immunohistochemical features are required for the final diagnosis of schwannomas in domestic animals.(AU)

Schwannoma with bone differentiation in a dog

A schwannoma with bone differentiation was diagnosed in a seven-year-old German Shepherd female dog. Clinical signs were those of limping and proprioceptive and neurological deficits. Superficial and deep sensitivity were lower and muscle atrophy of the left forelimb was marked. Two subscapular masses were detected at examination. Microscopic analysis of the masses disclosed a pronounced proliferation of either palisading or loosely arranged within a myxoid tissue spindle neoplastic cells intermingled with bone tissue islands. The neoplasm was positive for vimentin, $100 protein and GFAP.

Aspectos histoquímicos e imunoistoquímicos nos neoplasmas do sistema nervoso periférico / Histochemical and immunohistochemical features of peripheral nerve neoplasms

Doze casos de tumores do sistema nervoso periférico, sete schwannomas e cinco neurofibromas foram diagnosticados entre 1964 e 2004, em caninos e bovinos. Histologicamente, as células predominantes nos schwannomas eram fusiformes organizavam-se em paliçada ou em feixes aleatórios. Nos neurofibromas as células neoplásicas eram fusiformes e se originavam da periferia dos nervos formando ninhos e feixes. O tecido conjuntivo era mais abundante nos neurofibromas e os colágenos dos tipos I e III eram os principais constituintes desses neoplasmas. Os neurofibromas foram caracterizados por uma concentração alta e difusa de mastócitos, provavelmente devido à origem das células neoplásicas do perineuro e epineuro. A coloração de AgNOR não se mostrou eficiente como indicador de prognóstico nos neoplasmas analisados. Imunoistoquímicamente houve forte marcação para vimentina (100 por cento) e S100 (100 por cento) em ambos os tipos de tumor. A maioria dos schwannomas (75 por cento) foi positiva para a proteína ácida fibrilar glial; os neurofibromas só apresentaram marcação nas células de Schwann dos fascículos nervosos(AU)

A retrospective study of peripheral nerve tumors was made from 1964 to 2004. The tumors summed up 12, being seven schwannomas and five neurofibromas. Schwannomas were composed of spindle-shaped cells either in a palisading pattern or random bundles loosely textured and neurofibromas by spindle cells. The connective tissue components were more prevalent in neurofibromas with a characteristic deployment of collagens type I and III. In AgNOR techniques, both benign and malignant schwannomas and neurofibromas did not show differences. Mast cells stained by toluidine blue were more prevalent in neurofibromas which are rich in reactive endoneurium. Schwannomas (100 percent) and neurofibromas (100 percent) were positive for vimentin and S100 protein, so they prove to be reliable for the diagnosis of peripheral nerve tumors. GFAP marked cells were found in three schwannomas and in Schwann cells within neurofibromas(AU)

Exérese de Schwanoma por meio da técnica de hemilaminectomia dorsolateral cervical cranial

Os tumores intradurais-extramedulares representam 50% das neoplasias do sistema nervoso. A maioria dos tumores intradurais-extramedulares caninos corresponde a neoplasias de raízes nervosas (neurofibromas, neurofibrossarcomas, schwanomas) e meningiomas. Optamos por descrever um caso de schwanoma uma vez que não o são rotineiramente relatados. Este trabalho refere-se a um cão da raça Pastor Belga, macho, 8 anos, atendido no Serviço de Neurologia do Hospital de Clínicas Veterinárias da Faculdade de Veterinária da Universidade Federal do Rio Grande do Sul com histórico de déficit de reação postural e hemiparesia dos membros torácico e pélvico do lado direito. O exame mielográfico evidenciou existência de massa subdural-extramedular no lado direito junto à articulação atlanto-occipital, compatível com neoplasia. O cão foi submetido a tratamento cirúrgico utilizando-se hemilaminectomia dorsolateral cervical cranial e remoção parcial do material compressivo. Setenta e cinco dias após a cirurgia o animal apresentou sinais de piora. O exame mielográfico evidenciou aumento de volume do tumor em relação ao inicial. Foi realizada exérese do tumor, porém, ao término do procedimento cirúrgico o paciente foi a óbito; essa situação condiz com a literatura, onde apenas uma pequena porcentagem desses tumores é completamente removida e as recidivas são altas.

Schwannoma canino / Schwannoma in a dog

Foi atendida na Clínica Veterinária da UNIMAR uma cadela de 10 anos, SRD. O animal apresentava uma massa subcutânea no membro pélvico esquerdo. O tumor media 15 cm e tinha crescimento lento, mas progressivo. Formato ovoide, consistência firme, aderido à musculatura e acometia os plexos nervosos do nervo femoral. Microscopicamente a celularidade era alta, de padrão morfológico fusiforme, com células bem compactadas, pleomórficas e com disposição em paliçada. Observaram-se padrões Antoni A com células densamente agrupadas em arranjo paralelo e áreas Antoni B com arranjo irregular e ao acaso. A imuno-histoquímica revelou forte positividade para vimentina e proteína S-100, favorecendo a origem neural e fator VIII, confirmando a vascularização, pois também marcaram as células vasculares da neoplasia. O diagnóstico foi baseado nos exames citopatológico, histopatológico, histoquímico e imunohistoquímico, que confirmaram schwannoma canino.(AU)

A female SRD 10 year-old dog, was presented at the Veterinary Clinic UNIMAR. The animal had a subcutaneous mass in the left pelvic limb. The tumor measured 15 cm, and showed a steadily progressive growth. The neoplasm was ovoid, and was firmly attached to the muscles and the nervous plexus block. Microscopically the cellularity was high and composed of spindle pleomorphic compacted cells either as a palicade or a lattice. Antoni A pattern with densely-packed parallel arranged cells and Antoni B areas with irregular arrangement and design were observed. Immunohistochemistry revealed strong positivity of the neoplastic cells for vimentin and S-100 protein, favoring the neural origin and factor VIII, confirming the vasculature of the tumor. The diagnosis was based on cytopathology, histopathology, histochemical and immunohistochemical tests, which confirmed canine schwannoma.(AU)

Schwannoma canino / Schwannoma in a dog

Foi atendida na Clínica Veterinária da UNIMAR uma cadela de 10 anos, SRD. O animal apresentava uma massa subcutânea no membro pélvico esquerdo. O tumor media 15 cm e tinha crescimento lento, mas progressivo. Formato ovoide, consistência firme, aderido à musculatura e acometia os plexos nervosos do nervo femoral. Microscopicamente a celularidade era alta, de padrão morfológico fusiforme, com células bem compactadas, pleomórficas e com disposição em paliçada. Observaram-se padrões Antoni A com células densamente agrupadas em arranjo paralelo e áreas Antoni B com arranjo irregular e ao acaso. A imuno-histoquímica revelou forte positividade para vimentina e proteína S-100, favorecendo a origem neural e fator VIII, confirmando a vascularização, pois também marcaram as células vasculares da neoplasia. O diagnóstico foi baseado nos exames citopatológico, histopatológico, histoquímico e imunohistoquímico, que confirmaram schwannoma canino.

A female SRD 10 year-old dog, was presented at the Veterinary Clinic UNIMAR. The animal had a subcutaneous mass in the left pelvic limb. The tumor measured 15 cm, and showed a steadily progressive growth. The neoplasm was ovoid, and was firmly attached to the muscles and the nervous plexus block. Microscopically the cellularity was high and composed of spindle pleomorphic compacted cells either as a palicade or a lattice. Antoni A pattern with densely-packed parallel arranged cells and Antoni B areas with irregular arrangement and design were observed. Immunohistochemistry revealed strong positivity of the neoplastic cells for vimentin and S-100 protein, favoring the neural origin and factor VIII, confirming the vasculature of the tumor. The diagnosis was based on cytopathology, histopathology, histochemical and immunohistochemical tests, which confirmed canine schwannoma.

Exérese de Schwanoma por meio da técnica de hemilaminectomia dorsolateral cervical cranial

Os tumores intradurais-extramedulares representam 50% das neoplasias do sistema nervoso. A maioria dos tumores intradurais-extramedulares caninos corresponde a neoplasias de raízes nervosas (neurofibromas, neurofibrossarcomas, schwanomas) e meningiomas. Optamos por descrever um caso de schwanoma uma vez que não o são rotineiramente relatados. Este trabalho refere-se a um cão da raça Pastor Belga, macho, 8 anos, atendido no Serviço de Neurologia do Hospital de Clínicas Veterinárias da Faculdade de Veterinária da Universidade Federal do Rio Grande do Sul com histórico de déficit de reação postural e hemiparesia dos membros torácico e pélvico do lado direito. O exame mielográfico evidenciou existência de massa subdural-extramedular no lado direito junto à articulação atlanto-occipital, compatível com neoplasia. O cão foi submetido a tratamento cirúrgico utilizando-se hemilaminectomia dorsolateral cervical cranial e remoção parcial do material compressivo. Setenta e cinco dias após a cirurgia o animal apresentou sinais de piora. O exame mielográfico evidenciou aumento de volume do tumor em relação ao inicial. Foi realizada exérese do tumor, porém, ao término do procedimento cirúrgico o paciente foi a óbito; essa situação condiz com a literatura, onde apenas uma pequena porcentagem desses tumores é completamente removida e as recidivas são altas.