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Background: Multilobular tumor of bone (MTB) is an unusual neoplasm with variable biologic behavior which originates primarily in bone tissues. Radiographs computed tomography (CT), and magnetic resonance imaging (MRI) are useful in diagnoses and surgical planning. Tumor removal with wide surgical margins is the treatment of choice. Immunohistochemistry has been shown as an important tool in veterinary oncology to define therapeutic and prognostic decisions. The goal of this study was to report 2 distinct cases of multilobular tumor of bone, their Cox-2 and Mib-1 immunohistochemical profile and its impact on overall survival. Case: Two bitches were presented at the Oncology Department of the Veterinary Hospital in the Veterinary School of Universidade Federal de Minas Gerais (UFMG). Both had a history of a progressive, painless, circumscribed, and firm facial mass. The 1st patient was a 8-year-old intact bitch mixed breed, weighing 50 kg, that presented a fast growing right infraorbital 3-cm mass, causing eye displacement. The 2nd patient was a 7-year-old spayed bitch Labrador retriever, weighing 28 kg, that presented a left temporal 8-cm mass. Neurologic examination of both bitches was normal. Skin over the nodules was strained, but with no ulceration. Radiographic exams of the head revealed lytic and proliferative bone reaction, with loss of cortical definition in both cases. These alterations were seen on the left zygomatic arch of the retrobulbar region, involving part of the mandible and of the nasal sinus lateral frontal bone in 1st patient, and on the right temporal process of the zygomatic bone in 2nd patient. The last one, also showed a granular solid mass with little contact with skull bones. Complete blood count, biochemistry profile, electrocardiogram, and 3-view thoracic radiographs were performed. Results were within normal ranges for the species and no signs of metastasis was seen on the radiographs. Location, size, and density of the mass, adjacent tissue compression, absence of cranial invasion, and lymph node size were rigorously evaluated with CT, allowing an individualized surgical planning to achieve complete mass removal and maintenance of the function of adjacent structures. Both animals were submitted to surgery. Both tumors were fixed on 10% neutral buffered formalin and sent to the Animal Pathology Department of UFMG for histopathological examination and margin assessment. Both tumors were diagnosed as grade I MTB. Tumor immunohistochemistry was performed to identify prognostic factors that could be used to better define therapeutic treatments and to try to clarify the discrepancy in disease progression between both tumors. The 1st patient expressed 20% of Mib-1 and was considered score 2 of Cox-2. The 2nd one expressed 5% of Mib-1 and was considered score 1 of Cox-2. Considering the diagnoses and histological characteristics of the tumors, it was decided for clinical follow-up of patients without additional therapeutic complementation. Even considering incomplete surgical margins in 2nd patient, adjuvant chemotherapy was not performed, due to low mitotic index and low histological grade. The 1st patient had an overall survival of 240 days, and death was due to recurrence and disease progression; and the 2nd did not show recurrence nor metastasis after 1200 days. Discussion: Proper and individualized surgical planning and histopathological evaluation are extremely important to guide treatment decisions. However, immunohistochemistry can be important in MTB cases, to help define which patients should be submitted to surgery alone and which patients could be benefited from adjuvant chemotherapy.

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Background: Feline Injection Site-Associated Sarcoma (FISS) is a mesenchymal neoplasia of aggressive behavior thatdevelops in sites where vaccine or drugs were administered. FISS is clinically characterized by the appearance of asolitary firm nodule or a diffuse mass, adhered to tissues, in regions associated to vaccine or drug applications. Despitelow prevalence, tumor recurrence rates can reach 80%. FISS present more aggressive histological characteristics whencompared to sarcomas not associated to injection sites. The aim of this paper is to contribute towards the understandingof the biological behavior of FISS.Materials, Methods & Results: Sixteen samples of FISS were analyzed. Fibrosarcomas were the most frequent histological subtype (62.5%). Malignant peripheral nerve sheath tumor was diagnosed in 18.75% cases. Ten (62.5%) FISS wereclassified as grade II; 4/16 (25%) grade I, and 2/16 (12.5%) grade III. Cox-2 overexpression occurred in 3/16 (18.75%)samples, with positive correlation between Cox-2 expression and cellularity (r = 0.696, P = 0.003). Mitotic index lowerthan 9 events was found in 11/16 (68.7%) samples and between 10 and 19 mitotic events in 5/16 (31.3%) cases. MeanKi-67 expression was 2.39 ± 2.48%. FISS characterized as fibrosarcomas presented longer overall survival (median 545days) than other histological subtypes (median 130.5 days) [P = 0.01].Discussion: Patients with FISS generally present with larger nodules than those with sarcomas not associated to injections,suggesting a challenge for pet owners to note subcutaneous tumors in the interscapular region, in addition to the aggressivebiological behavior of FISS. The influence of size on prognosis remains controversial. An association between histologicgrade and the development of metastasis has been observed, with patients with grade III FISS associated with an increasein the metastatic rate. The present study did not find a correlation between overall survival...

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Background: Melanoma is the most frequent cancer in the canine oral cavity. It shows an aggressive behavior, characterized by rapid and invasive growth and high metastatic potential. Metastasis is seen in more than 80% of dogs at time ofdeath. Adjuvant therapy should be recommended because of potential recurrence and metastasis. Oral melanoma has a poorprognosis even when adjuvant treatments are used. There are some treatment options, but the high death rate due to thedisease is still a challenge. The aim of this study was to assess the overall survival of dogs diagnosed with oral melanomaand treated with adjuvant chemotherapy and immunotherapy.Materials, Methods & Results: A retrospective analysis was carried out in 20 dogs with oral melanocytic or amelanocyticmelanomas. Cases were staged according to a modified World Health Organization clinical staging system for canine oralmalignant melanoma. Tumor size (T1: 4 cm), regional metastasis (N0: no metastasis; N1:metastasis) and presence of distant metastasis (M0: no metastasis; M1: metastasis) are evaluated. Then, cases were dividedinto 4 stages: I (T1 N0 M0), II (T2 N0 M0), III (T3 N0-1 M0, Tx N1 M0) and IV (Tx Nx M1). Diagnoses were confirmedwith histopathological exam and immunohistochemistry (IHC) when necessary. In poorly differentiated neoplasms, IHC wasperformed at the request of the submitting veterinarian using specific markers PNL-2 and Melan-A. Animals were dividedinto 2 groups: dogs submitted to surgery alone were included in group 1 (G1); dogs submitted...

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Background: Peripheral neuropathies result in sensory, motor or autonomic dysfunctions due to impairment of peripheral spinal or cranial nerves. Neoplasms such as lymphoma are cited as one of the many aetiological causes and it mayaffect the nerve directly, by compression, or indirectly (paraneoplastic) by remote action of the neoplasm located in anextra-neural site. This study aimed to report two cases of cranial nerve neuropathy (trigeminal and facial) associated withcanine lymphoma, contributing to a better understanding of its paraneoplastic effects on the nervous system, as well asthe diagnosis and treatment of these conditions.Cases: Two cases of canine lymphoma associated with possible signs of paraneoplastic peripheral neuropathy were attendedat the Veterinary Hospital from the Universidade Federal de Minas Gerais (HV UFMG). Case 1. A spayed mixed breedbitch, with lethargy and unilateral exophthalmos. Brain computed tomography revealed a retrobulbar mass and cytology wasdiagnostic for extranodal lymphoma. Subsequent to computed tomography, the dog was presented with hypotrophy of thefacial musculature and difficulty in grasping food, consistent with trigeminal nerve palsy, which resolved after institutionof the 19-week chemotherapy protocol from the University of Wisconsin. Nevertheless, disease reccurred and a rescueprotocol was initiated. Case 2. A female Dalmatian, spayed, was diagnosed with multicentric lymphoma, after cytologyof the left mandibular lymph node. Chemotherapy was initiated with the same protocol of the previous case. However,the disease progressed and it was observed facial asymmetry with ptosis of the left eyelid, pina and lips, in addition todifficulty in grasping food, suggesting facial and trigeminal cranial nerve palsy. Clinical signs resolved after institutionof a rescue chemotherapy protocol. However, in both cases, disease progression and poor clinical condition resulted in...

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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.[...]

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Mammary neoplasms are described as the third most common type of feline tumor, after haematopoietic and skin tumors, and present a challenge for clinicians because the prognosis for feline mammary tumors ranges from guarded to poor. Thus, it is necessary to define new therapeutic approaches and establish more in-depth knowledge about this disease in felines. The main aspects of the diagnosis, prognosis and treatment of feline mammary neoplasia were discussed, aiming to standardize the criteria and to serve as a guide for pathologists and veterinary clinicians.

As neoplasias mamárias são descritas como o terceiro tipo mais frequente de tumor em felinos (após as neoplasias hematopoiéticas e cutâneas) e apresentam um desafio para os clínicos devido ao prognóstico, que varia de reservado a ruim. Assim, é necessário conhecer melhor essa doença em felinos e definir novas abordagens terapêuticas. Discutiu-se os principais aspectos de diagnóstico, prognóstico e tratamento da neoplasia mamária felina, com o objetivo de padronizar os critérios e servir de guia para patologistas e clínicos veterinários.

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Mammary neoplasms are described as the third most common type of feline tumor, after haematopoietic and skin tumors, and present a challenge for clinicians because the prognosis for feline mammary tumors ranges from guarded to poor. Thus, it is necessary to define new therapeutic approaches and establish more in-depth knowledge about this disease in felines. The main aspects of the diagnosis, prognosis and treatment of feline mammary neoplasia were discussed, aiming to standardize the criteria and to serve as a guide for pathologists and veterinary clinicians.(AU)

As neoplasias mamárias são descritas como o terceiro tipo mais frequente de tumor em felinos (após as neoplasias hematopoiéticas e cutâneas) e apresentam um desafio para os clínicos devido ao prognóstico, que varia de reservado a ruim. Assim, é necessário conhecer melhor essa doença em felinos e definir novas abordagens terapêuticas. Discutiu-se os principais aspectos de diagnóstico, prognóstico e tratamento da neoplasia mamária felina, com o objetivo de padronizar os critérios e servir de guia para patologistas e clínicos veterinários.(AU)

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Extramedullary plasmacytomas (EPs) are responsible for 2.5% of neoplasms in dogs. They are solitary, smooth, elevated, pink or red nodules, of 1 to 2cm in diameter. Cutaneous and oral extramedullary plasmacytomas in dogs are usually benign tumors, treated with local therapies. Prognosis is generally good. Recurrence and metastatic rates are low. Electrochemotherapy is a local treatment that combines chemotherapy and electroporation and shows objective responses of 70% to 94% with few local and systemic side effects. This scientific communication has the objective to report treatment of three canine patients with oral extramedullary plasmacytoma. Nodules were located on the tongue and patients were submitted to one or two electrochemotherapy sessions, which preserved the tongue without mutilation and cured the patients.

Plasmocitomas extramedulares (PE) são responsáveis por 2,5% das neoplasias em cães. São nódulos solitários, lisos, elevados, rosados ou avermelhados, de 1 a 2cm de diâmetro. O plasmocitoma extramedular cutâneo e oral em cães é um tumor tipicamente benigno tratado com terapias locais. O prognóstico geralmente é bom. As taxas de recorrência e metástase são baixas. A eletroquimioterapia é um tratamento local que combina quimioterapia e eletroporação e mostra respostas objetivas entre 70 a 94% com poucos efeitos colaterais locais e sistêmicos. Esta comunicação científica teve como objetivo relatar o tratamento de três pacientes caninos com plasmocitoma extramedular oral com lesões localizadas na língua submetidos a uma ou duas sessões de eletroquimioterapia, o que permitiu a manutenção da língua sem mutilação e proporcionou a cura dos pacientes.

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ABSTRACT: Targeted therapy of neoplasms is an emergent approach in human and veterinary medicine. Cyclooxygenase (COX) is a class of catalytic enzymes related to the formation of inflammatory mediators. COX-2 is expressed constitutively in a few body tissues, but it may be induced in specific pathophysiologic conditions, such as cancer. COX-2 expression in neoplams may be considered a potential predictive factor, due to the possible association of selective COX-2 inhibitors in adjuvant treatments. This scientific communication has the objective to report COX-2 expression in seven neoplasms of dogs and the usage of adjuvant treatment with COX-2 selective inhibitors as an effective and feasible option in cancer treatment.

RESUMO: O tratamento direcionado das neoplasias é uma abordagem emergente tanto na medicina humana, quanto na veterinária. A cicloxigenase (COX) é uma classe de enzimas catalíticas relacionada à formação de mediadores inflamatórios. A COX-2é expressa de forma constitutiva em poucos tecidos, mas pode ser induzida em condições patofisiológicas específicas, como os processos neoplásicos. A expressão da COX-2 em neoplasias pode ser considerada um fator preditivo em potencial, tendo em vista a possibilidade de associação de inibidores seletivos para COX-2 em tratamentos adjuvantes. Esta comunicação científica teve como objetivo relatar a expressão de COX-2 em neoplasias de sete cães e o tratamento adjuvante com inibidores seletivos para COX-2 como uma opção efetiva e viável no tratamento do câncer.

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Background: The proliferative disorders of mast cells include, in addition to mast cell tumor, systemic mastocytosis and myeloid leukemia of mast cells. Surgery is the treatment of choice for tumors in the skin, in regions which allow wide excision but adjuvant treatments should be performed in selected patients. However, the use of adjuvant chemotherapy remains empirical, due to the absence of controlled studies. Despite the relevance of the use of tyrosine kinase inhibitors for the treatment of mast cell tumors, studies with these drugs have focused primarily on neoadjuvant scenery. Case: A 13-year-old male Poodle dog, weighing 4.6 kg, was presented with bilateral increase in inguinal lymph nodes and a vesicular cutaneous lesion, in the inguinal region, 75 days after surgery for the removal of a scrotum grade II mast cell tumor. Patient was admitted for surgery and the tissues removed were sent for pathological examination that allowed the diagnosis of grade II mast cell tumor and metastasis in all inguinal lymph nodes. The immunohistochemical study for CD117 revealed an aberrant expression of KIT receptor (KIT II), while the PCR for mutations in exon 11 of c-KIT gene revealed internal tandem duplications. The patient underwent a session of chemotherapy with lomustine, however it had serious side effects that resulted in discontinuation of treatment, opting for utilization...

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Background: Peripheral neuropathies secondary to chemotherapy drugs, especially when it comes to the use of vincristine, are common in humans, but rare in dogs. Neurologic manifestation depends on the kind of axonal fibers involved. When motor fibers are affected, weakness and ataxia are observed. Sensory fibers involvement, which can lead to hyperesthesia, hypoesthesia or paresthesia was reported experimentally in rats, and is common in humans but were never reported in dogs. Thus, this report aims at describing a mixed neuropathy, with sensory and motor involvement, in a dog after vincristine treatment. Case: A one year old mixed breed dog, rescued from the street, was presented with multiple nodular and ulcerated lesions, disseminated on the head, gums, flank and limbs, with progressive worsening in the last two months. Cytology of two subcutaneous and one gum nodule revealed an intense concentration of neutrophils and round cells with abnormally clumped chromatin patterns, prominent nucleoli and multiple cytoplasmic vacuoles, compatible with TVT. Treatment was initiated with a weekly administration of vincristine (0,75 mg/m2 ) combined with anti-emetic (maropitant) and H1 receptor inhibitor (ranitidine). Fast remission of the cutaneous lesions occurred. However, after the second chemo session, generalized hyperesthesia, mild ataxia, intermittent collapse and vomiting were...

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The aim of this study was to present clinico-pathological data, therapeutical conduct and overall survival of canine mammary lesions attended at the Veterinary Hospital of the Veterinary School of the Federal University of Minas Gerais (UFMG) in Belo Horizonte, Minas Gerais, Brasil.[...]

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Tumores intracranianos representam a principal causa de disfunção neurológica em animais de meia idade a idosos. O objetivo dessa revisão foi detalhar os aspectos clínico-patológicos dessas afecções. O acometimento secundário do tecido nervoso intracraniano, por extensão tumoral ou lesões metastáticas, é mais comum em relação às neoplasias primárias. No entanto, o meningioma é a principal neoplasia extra-axial primária de cães e gatos, enquanto os gliomas (astrocitoma e oligodendroglioma), ependimomas e tumores do plexo coróide representam os principais processos intra-axiais. Os sinais neurológicos decorrentes de neoplasias intracranianas dependem da localização, extensão e taxa de crescimento do tumor. O diagnóstico definitivo só é possível após o exame histopatológico do tecido tumoral, no entanto diagnósticos presuntivos podem ser obtidos a partir do exame clínico e exames de imagem, com destaque para a tomografia computadorizada e ressonância magnética. O prognóstico de cães e gatos com neoplasias intracranianas pode ser significativamente alterado a partir do tratamento com cirurgia, radioterapia e quimioterapia, utilizados isoladamente ou em combinação. No entanto, o elevado custo de implantação da radioterapia e a morbidade e mortalidade associadas à neurocirurgia limitam a biópsia e o tratamento cirúrgico aos centros veterinários que disponham de alta qualificação e técnicas avançadas de anestesia e cuidados críticos.

Intracranial tumors are the leading cause of neurological dysfunction in companion animals of middle aged and older. The objective of this review was to detail the clinical and pathological aspects of these conditions. Primary intracranial neoplasms of the nerve tissue are less frequent than secondary involvement by tumor extension or metastatic lesions. Meningiomais the main extra-axial primary neoplasm of cats and dogs as gliomas (astrocytoma and oligodendroglioma), ependymomas and choroid plexus tumors represent the major intra-axial processes. Neurological signs resulting from intracranial tumors depend on the location, extent and rate of tumor growth. The definitive diagnosisis only possible after histopathological examination of tumor tissue, however clinical suspicion maybe obtained from the clinical examination and imaging studies, particularly computed tomography and magnetic ressonance image.The prognosis for dogs and cats with brain tumors can be significantly improved from the treatment with surgery, radiotherapy and chemotherapy, used alone or in combination. However, the high deployment cost of radiation therapy and morbidity and mortality associated with neurosurgery limits biopsy and surgical treatment to veterinary centers that have high qualification and advanced techniques of anesthesia and critical care.

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Background: Urethral neoplasias are rare in small animals and normally have slow growth, but tissue invasion and urethral obstruction are frequent. Prognosis usually is poor due to the high degree of malignity of the main neoplasias involved. Surgical excision is the main form of treatment, but it should be complete with wide safety margins, making partial or complete removal of the bladder with transplantation of the ureters necessary. This report aims at describing a surgical technique, used in a bitch with urethral tumor, which involved complete resection of vulva, vagina and bladder, followed by ureterocolic anastomosis without pelvic osteotomy. Case: A 10-year-old female White Swiss Shepherd dog, weighing 35 kg, was presented with partial ischuria and haematuria for approximately 30 days, with final development of complete ischuria, vomit and anorexia. Urethral swab was performed, and the material obtained was fixed for cytological examination, which revealed the presence of malignant epithelial neoplasias, giving the case a direction. Staging was achieved through thoracic radiographs in two recumbent views, and metastatic lesions were not found. A radical surgery was proposed to the owner for the treatment of the patiente. The surgical procedure involved complete removal of the lower urinary tract, vagina and vulva, followed by reimplantation of the ureters in the colon (ureterocolic anastomosis). The patient recovered well from surgery, and urinary continence was maintained, along with quality of life. Transitional carcinoma in the urethral mucosa was characterized by histological diagnose, which revealed safe margins. Clinical evaluations were made daily, with detailed observation of urination, urine volume and color. From the second postoperative day on, fecal consistency from pasty to liquid and fetid odor were observed. Control of urination was only achieved after the fifth day. Ten days after the surgery, the patient was discharged, when the external sutures were removed. The patient lived well for six months, when it died of an indeterminate cause. Necropsy was not allowed by the owner. Discussion: Although primary urethral neoplasias are considered to be rare in dogs, its incidence is higher in females with age around 10 years, as was observed in this case report. Surgery may be the most promising treatment for urethral neoplasias in dogs, since they are not considered chemosensitive and the results of radiotherapy do not seem satisfactory. Urethral reimplantation on the digestive tract is an old technique described in the literature with satisfactory results, but with a lot of reports of postoperative complications which did not occurred in this case. Cystectomy followed by ureterocolic anastomosis allows the bladder to be completely excised while maintaing urinary continence and quality of life. The technique used was proved suitable for the treatment of urethral neoplasias that require complete removal of lower urinary tract so that wide margins are achieved. The approach used, as described, is less complicated than the ventral approach with pubic osteotomy. The described technique, without pelvic osteotomy, may benefi t patients with urethral neoplasias, once it is a less painful procedure, with fewer post-operative complications. Good patient recovery and wide margins obtained are sufficient to valorize this surgical technique.

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Background: Sinus adenocarcinomas of papillary pattern are neoplasms rarely described in dogs and most cases are characterized by slow growth, local invasion and rare cases of metastasis. Their characteristics are presence of glandular structures that may have papillary pattern, tubulo-papillary, acinar and mixed pattern. Approximately 80% of primary nasal tumors are malignant and adenocarcinomas are the most frequently histology type. This paper reports a case of papillary adenocarcinoma of nasal sinus in the dog, emphasizing the use of histochemical and immunohistochemical techniques to aiding for appropriate therapy. Case: A 14-year-old male Poodle dog, presenting seropurulent nasal discharge, frequent sneezing and an enlargement in the nasal region, was submitted to surgical excision of a tumor. Macroscopically, was observed fragment coated with soft hairy skin and shear blackish color, and some fragments associated with more firm tissues like cartilage and bone tissue. Tumor specimens were collected, fixed in 10% neutral buffered formalin solution and embedded in paraffin. Afterwards, 4 µm histological sections were obtained and stained with HE. For immunohistochemical analysis a biotin-peroxidase system was used and secondary antibodies were identifi ed using Advance HRP. CKAE1/AE3, CK34ßE12, SMA, E-cadherin, Cox-2, Ki-67 and Her-2 expression were evaluated. For CK AE1AE3 antibody a qualitative method was used and neoplasia were classified as negative (-) or positive (+) and for CK34ßE12 was used semiquantitative evaluation and neoplasms were classified as negative (-), positive with focal staining (+) and positive with diffuse staining (++). The graduation for HER-2 expression was (+) for 4 (++++), were 4 (++++) was the most intensity membrane staining. For Cox-2 the system used was semiquantitative and the distribution was scored by estimating the percentage of tumor cells staining. Intensity was estimated on a scale from 0 (absent) to 12 (strong). The proliferative index was calculated by counting nuclei positive for Ki-67 (anti-MIB-1) in a total of 1000 neoplastic cells. Microscopically, was observed a proliferation of epithelial cells in papillary arrangement with delicate connective axis of support and areas of stromal invasion, and the tumor received the diagnosis of papillary adenocarcinoma of nasal sinus. Immunohistochemical analysis revealed strong staining for Cox-2 (score 12), CKAE1/AE3 positivity and CK34ßE12 (+ + +) and negative for Her-2 (+). Loss of E-cadherin expression was observed and SMA allowed the visualization of areas of basal membrane rupture. The rate of proliferation was evaluated by means of the expression of MIB-1 was high (16%). Chemotherapy was performed with carboplatin and gemcitabine. Discussion: Sinus carcinomas in general, despite their slow growth, are locally invasive and cause extensive destruction of adjacent tissues. In this case, the immunohistochemical analysis presented positive expression of CK AE1/AE3 and CK34ßE12, indicating epithelial histogenesis with basal phenotype. Strong intensity of COX-2 expression was observed, indicating a poor prognostic for the patient. The loss of expression of E-caderin, areas of invasive tumors and high rate of cell proliferation, demonstrated the aggressive character of papillary adenocarcinoma nasal sinus. Surgery with chemotherapy- associated was effective and tolerant treatment. Diagnosis was based on histopathological and immunohistochemical analysis. Correct characterization of this neoplasm associated with the appropriate therapy aided in prognosis and in the improvement of the animal's quality of life. The patient's overall survival has been evaluated since the surgical procedure up to this date and is over 18 months.

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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.

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.

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O carcinoma de células escamosas (CCE) é uma neoplasia maligna oriunda dos queratinócitos do estrato germinativo/espinhoso da epiderme cuja patogenia encontra-se intimamente relacionada à exposição solar. Este trabalho tem como objetivo relatar a utilização da quimioterapia intralesional com carboplatina em uma gata siamesa, de dez anos de idade, que apresentava lesão ulcerada na face com exposição das fossas nasais e diagnóstico histológico de CCE. A paciente apresentava dificuldade respiratória pelo comprometimento das estruturas intranasais, sendo observada redução significativa da lesão no plano nasal e melhora da dificuldade respiratória após o término das quatro sessões. Ocorreram efeitos colaterais associados ao tratamento, como apatia e perda de apetite, o que impediu a realização da quimioterapia semanalmente. O intervalo entre as aplicações foi, portanto, de catorze dias.

Squamous cell carcinoma (SCC) is a malignant neoplasm arising from keratinocytes of the stratum germinativum / spinosum of the epidermis, and it’s pathogenesis is closely related to sun exposure. The objective of this paper is to report on the use of intralesional chemotherapy with carboplatin in a ten-year-old Siamese cat who had an ulcerated lesion on the face with exposure of nostrils and histological diagnosis of SCC. The patient had difficulty in breathing due to the involvement of intra-nasal structures, but showed significant reduction of the lesion in the nasal plane and of respiratory distress after the end of four sessions. Associated to the treatment, the patient developed side effects such as apathy and loss of appetite, which prevented the use of chemotherapy on a weekly basis. The interval between sessions was therefore 14 days.

El carcinoma de células escamosas (CCE) es un tumor maligno originado en las células del estrato germinativo de la piel, cuya patogenia se halla íntimamente relacionada con la exposición solar. Este trabajo tiene como objetivo presentar la utilización de la quimioterapia intratumoral con carboplatino, en una gata siamesa de diez años que tenía una lesión ulcerada en la cara, con exposición de cavidad nasal y diagnóstico previo de CCE. La paciente presentaba dificultad respiratoria debido al compromiso de las estructuras intra nasales. Se pudo observar una reducción significativa de las lesiones y mejoría de la calidad respiratoria después de cuatro sesiones de quimioterapia. El tratamiento tuvo efectos colaterales, tales como apatía y pérdida del apetito, que impidieron la realización de la quimioterapia en forma semanal, pasando a un intervalo de aplicaciones de catorce días.

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O tumor venéreo transmissível (TVT) e o sarcoma histiocítico (SH) são neoplasias malignas de células redondas e origem mesenquimal. Apesar das semelhanças, o comportamento tumoral, o prognóstico e o tratamento são muito distintos. Este trabalho tem como objetivo relatar um caso de TVT com disseminação extragenital, cujo diagnóstico histopatológico inicial havia sido sugestivo de SH. A cadela foi submetida ao tratamento quimioterápico com doxorrubicina e apresentou remissão completa das lesões após quatro sessões, o que não era esperado para o SH. A revisão das características histológicas, associadas à marcação imuno-histoquímica positiva para vimentina e negativa para E-caderina, permitiu concluir que se tratava de um TVT de apresentação extragenital. Este trabalho evidencia a importância do uso de marcadores imuno-histoquímicos nos casos em que se suspeita de TVT com disseminação extragenital, principalmente naqueles em que o diagnóstico inicial não foi conclusivo.

The transmissible venereal tumor (TVT) and histiocytic sarcoma (HS) are both malignant round cell neoplasms that have mesenchymal origin. Despite the similarities, tumor behavior, prognosis and treatment are very different. This article reports a case of TVT with extragenital dissemination, with an initial histopathological diagnosis that was suggestive of HS. The dog was submitted to chemotherapy with doxorubicin and showed complete remission of lesions after four sessions, which was not expected for HS. A review of the histological features of the tumor, associated with positive immunohistochemical staining for vimentin and negative for E-cadherin, allowed us to conclude that it was an extragenital TVT. This paper shows the importance of immunohistochemical stainings in TVT cases with extragenital dissemination, mainly when initial diagnosis is not conclusive.

El tumor venéreo trasmisible (TVT o Tumor de Sticker) y el sarcoma histiocítico (SH) son tumores malignos de células redondas de origen mesenquimático. A pesar de ser semejantes, ambos tumores tienen diferentes comportamientos, pronósticos y tratamientos. El presente trabajo tiene como objetivo relatar un caso de TVT con diseminación extragenital, cuyo diagnóstico histopatológico inicial había sugierido la presencia de un SH. La perra recibió un tratamiento quimioterápico con doxorrubicina y tuvo remisión completa de las lesiones después de la cuarta sesión, hecho no esperado para un SH. La revisión histológica a través de marcación inmunohistoquímica, fue positiva para vimentina y negativa para E-caderina, permitiendo concluir que se trataba de un TVT de presentación extra genital. Este trabajo evidencia la importancia del uso de marcadores inmuno-histoquímicos en casos de TVT con diseminación extragenital, principalmente en casos en los que el diagnóstico inicial genera algún tipo de duda.

Resumo

O carcinossarcoma é um tumor maligno, pouco frequente em cães, composto por células do tecido epitelial e mesenquimal. Constatar alterações bioquímicas, hematológicas e determinar um possívelmarcador tumoral circulante (MTC) seria de extrema importância para avaliar a resposta do organismofrente ao tumor e ao tratamento. Marcadores tumorais permitem conhecer a presença, evoluçãoou resposta terapêutica de um tumor maligno. Neste trabalho, relata-se o caso de uma cadela da raça poodle de 12 anos de idade que apresentava carcinossarcoma na mama torácica com metástase para linfonodos e pulmão, sendo submetida à mastectomia radical. Como proposta de identifi car marcadores tumorais confi áveis para acompanhar a evolução da doença, realizou-se testes laboratoriais dehemograma completo, LDH (desidrogenase láctica), fosfatase alcalina, cálcio, fósforo e CEA (AntígenoCarcinoembrionário – MTC). Foi possível evidenciar uma elevada concentração sorológica de CEAem coleta realizada no pré- cirúrgico, sugerindo sua utilização como possível marcador tumoral paraauxiliar no diagnóstico do câncer de mama avançado em cadelas

The carcinosarcoma is a malignant tumor, uncommon in dogs, composed of cells of mesenchymaland epithelial tissue. Search for biochemical and hematological changes, and determine a possibletumor marker (TM) would be extremely important to assess the body’s response against the tumorand treatment. Tumor markers allow us to know the presence, progression or therapeutic response ofa malignant tumor. Here we report a case of a female dog, poodle 12 year-old that had mammary carcinosarcomawith metastasis to thoracic lymph nodes and lungs, and underwent radical mastectomy.As a proposal to identify reliable tumor markers for monitoring disease progression, we carried outlaboratory tests hemogram, LDH (lactic dehydrogenase), alkaline phosphatase, calcium, phosphorusand CEA (Carcinoembryonic Antigen -TM). The results showed a high concentration of CEA in serologicalsamples were collected pre-surgery, suggesting its possible use as a tumor marker for thediagnosis of advanced mammary cancer in female dog