Pilot study to evaluate isolation by size of circulating tumour cells in canine oral melanoma.

Liquid biopsy for circulating tumour cell (CTC) detection is generally unexplored in veterinary medicine. Dogs with highly aggressive and heterogeneous tumours, such as oral malignant melanoma (OMM), could benefit from studies involving size-based isolation methods for CTCs, as they do not depend on specific antibodies. This pilot study aimed to detect CTCs from canine OMM using Isolation by Size of Epithelial Tumor Cells (ISET), a microfiltration methodology, followed by immunocytochemistry (ICC) with Melan-A, PNL2, and S100 antibodies. Ten canine patients diagnosed by histopathology and confirmed as OMM by immunohistochemistry were enrolled, their prognostic data was assessed, and blood samples were collected for CTC analysis. Results have shown the detection of intact cells in 9/10 patients. ICC has shown 3/9 Melan-A-positive, 3/9 PNL2-positive, and 8/9 S100-positive patients, confirming the importance of opting for a multimarker assay. A significant number of negative-stained CTCs were found, suggesting their high heterogeneity in circulation. Microemboli stained with either PNL2 or S100 were found in a patient with a high isolated cell count and advanced clinical stage. Preliminary statistical analysis shows a significant difference in CTC count between patients with and without lymph node metastasis (p < .05), which may correlate with tumour metastatic potential. However, we recommend further studies with more extensive sampling to confirm this result. This pilot study is the first report of intact CTC detection in canine OMM and the first application of ISET in veterinary medicine, opening new possibilities for liquid biopsy studies in canine OMM and other tumours.

Histopathological Results of Mouth Lesions in Dogs and Cats from Colombia.

Mouth-related neoplastic and non-neoplastic lesions are commonly found in dogs and cats, and their diagnosis and classification are important for treatment planning and prognosis. This retrospective study analyzed mouth-related lesions in dogs and cats between 2000-2019 from the animal pathology laboratory of the Universidad de Antioquia, Medellín, Colombia. A total of 640 mouth-related lesions affecting 572 dogs (89.4%) and 68 cats (10.6%) were reviewed. Lesions were classified as neoplastic or non-neoplastic. The average age for neoplastic lesions was 8.6 years in dogs and 6.4 years in cats, while for non-neoplastic lesions the average age was 7.7 years for dogs and 5 years for cats. Data was analyzed using descriptive statistical methods according to year and source of report, demographic information for the animal, location of the lesion, and diagnosis. Tissue origin and behavior were variables considered for neoplastic lesions. Melanoma was the most common neoplasia in dogs and squamous cell carcinoma was most common in cats. The most frequent non-neoplastic lesion in dogs was gingival hyperplasia, while in cats the inflammatory lesions showed a wide range of morphological diagnoses. This study described many pathological lesions affecting the oral cavity for both dogs and cats and provides useful epidemiological data for both pathologists and clinicians.

Lesions of the oral cavity of dogs: 720 cases / Lesões da cavidade oral de cães: 720 casos

Seven hundred twenty cases of oral cavity lesions in dogs were diagnosed from 2015 to 2020 in Distrito Federal, Brazil. Four hundred thirty-two (60%) lesions were neoplastic, and 288 (40%) were non-neoplastic. Of the neoplasms, 229 (53%) were considered malignant and 203 (47%) benign, affecting mainly males, of 43 different breeds, with an average age of 9.4 years, mainly the gum and lip. Melanoma was the most (96/432, 22.2%) commonly diagnosed neoplasm, followed by peripheral odontogenic fibroma (68/432, 15.7%), papilloma (63/432, 14.5%) and squamous cell carcinoma (SCC) (56/432, 12.9%). Non-neoplastic lesions also affected males predominantly, from 41 different breeds, with an average age of 8.9 years, mainly in the gums, lip, and tongue. These lesions were diagnosed as inflammatory (230/288, 79.8%), hyperplastic (47/288, 16.3%) and other lesions (11/288, 3.8%).

Foram estudados 720 casos de lesões na cavidade oral em cães diagnosticados entre 2015 e 2020, no Distrito Federal. Dessas alterações, 432 (60%) foram neoplásicas e 288 (40%) não neoplásicas. Dentre os neoplasmas, 229 (53%) foram consideradas malignos e 203 (47%) benignos, acometendo principalmente machos, de 43 raças diferentes, com idade média 9,4 anos, afetando principalmente gengiva e lábio. Melanoma foi o neoplasma mais comumente diagnosticado (96/432; 22,2%), seguido do fibroma odontogênico periférico (68/432; 15,7%), papiloma (63/432; 14,5%) e carcinoma de células escamosas (56/432; 12,9%). As lesões não neoplásicas também acometeram predominantemente machos, de 41 raças diferentes, com idade média 8,9 anos, afetando principalmente gengiva, lábio e língua. Essas lesões foram diagnosticadas como inflamatórias (230/288; 79,8%), hiperplásicas (47/288; 16,3%) e como outras alterações (11/288; 3,8%).

Malignant alveolar neoplasm in a 10-month-old French bulldog

Background: Malignant tumors are the main cause of death or euthanasia in animals. The oral cavity ranking fourth in number of occurrences. Epidemiological studies with dogs suggest that canine cancer kills 40-50% of individuals aged over 10 years. In view of the interest of academics and professionals in the healthcare of dogs and cats, this paper reports the case of a 10-month-old bitch, which, despite being a young animal, was affected alveolar rhabdomyosarcoma of abrupt evolution. Case: A 10-month-old French Bulldog bitch, weighing 10 kg, was referred to a veterinary hospital in the city of Rio de Janeiro for care. It had a history of mouth bleeding, after chewing a solid mineral material, edema in the region of the right maxilla, and protusion of the gland of the third eyelid. As the clinical examination also revealed a fracture of the maxillary canine, anti-inflammatory and antibiotics were prescribed, to be administered by the owner once a day for 7 days. During the next clinical examination, carried out one week later, an edema was found in the right region of the mouth, which proved difficult to examine. As the patient had already eaten, an appointment was made for the following day for an intervention in the operating room, where the animal could be anesthetized for better observation of the effected region. Blood was collected for hemogram, urea, creatinine, alkaline phosphatase, ALT, and GGT, and an 8 h food fasting and a 4 h water fasting were recommended. On that date, once the dog had been taken to the operating room, was administered the pre anesthesia, in addition to anesthetic induction and manutention. Upon examining the oral cavity, several loose molars were found on the right side, in addition to a tumoral aspect of the gum; thus, it was decided to collect a small sample of the tumoral mass for histopathology. The surgical specimen was placed in a formalin solution and sent to the laboratory for histopathological processing and diagnosis. One week later, the tumor mass was larger and the edema in the right region of the mouth was much larger than on the day of the procedure. Thus, a computerized tomography was requested to further investigate the alterations that had occurred in such a short time. Due to the results of the histopathology and the CT, an immunohistochemical test was suggested which determined the cell profile and morphology and confirmed the diagnosis of alveolar rhabdomyosarcoma according to clinical suspicion. The animal remained in the veterinary hospital for a further 48 h, during which the clinical condition worsened, with the animal suffering heavy bleeding. As the patient was no longer capable of oral intake of food or water, the decision was made with the consent of the owners to induce a painless death to alleviate the suffering of the animal. However, the owners did not authorize a necropsy. Discussion: Veterinary physicians should be conscious of the treatment of serious illnesses that will not result in a benefit for the patient. They should know when to stop the treatment to not cause further pain and suffering to the animals and their owners. Many of the interventions which aim to treat severe malignant neoplasia will not promote an improvement in quality of life or significantly extend the patient's survival, and do not justify the suffering they entail. A painless death remains the best alternative in such cases.

Treatment of canine oral melanoma with adjuvant chemotherapy and immunotherapy

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: < 2 cm; T2: 2 - 4 cm; T3: > 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...(AU)

Clinical, anatomopathological, and immunohistochemical findings of a transitional cell carcinoma from nasal cavity, frontal and ethmoidal sinus with meningoencephalic invasion in a dog.

Background: Primary neoplasms of the nasal cavity and sinuses are uncommon in domestic animals, most of which are of epithelial origin, being adenocarcinoma the most common tumor diagnosed in this region. Some malignant nasal cavity neoplasms may invade the brain causing clinical neurological signs, as well as purulent nasal secretion and epistaxis. Case Description: A case of neoplasm is reported in a 14-year-old pincher presenting dyspnea, epistaxis, and neurological alterations. Necropsy revealed the presence of a mass in the oral cavity vestibule, and another in the whole nasal cavity with invasion of the cribiform plate, meninges and brain. Squamous cells carcinoma was diagnosed in the oral cavity and transitional carcinoma in the nasal cavity. The immunohistochemistry confirmed that the brain infiltration was of the same origin as the nasal cavity neoplasm. Conclusion: The present report describes a rare case of transitional carcinoma of the nasal cavity as well as the frontal and ethmoidal sinuses with brain invasion, confirmed by immunohistochemistry. It is extremely important for veterinarians to include neoplasms in their differential diagnoses, when these animals show chronic respiratory signs and neurological alterations that do not improve with appropriate treatment, always associating with complementary exams, for correct diagnosis establishment and prognosis formulation.

Intratumoral T-Lymphocyte Subsets in Canine Oral Melanoma and Their Association With Clinical and Histopathological Parameters.

Canine oral melanoma is a common, aggressive tumor with limited treatment options. Tumor-infiltrating lymphocytes (TILs) are important in antitumor immunity. This study used histopathology and immunophenotyping by flow cytometry to evaluate the presence and distribution of TILs in canine oral melanoma, including the frequency of CD8+ T cells, CD4+ T cells, and regulatory T cells. Fifty samples of oral melanoma from 45 dogs that did not receive treatment prior to surgery were included in the study. The distribution of TILs in the tissue (brisk, nonbrisk, and absent) was evaluated in 48 samples. Twenty-eight (58%) samples had a brisk distribution pattern, 10 (21%) samples had a nonbrisk pattern, and 10 (21%) samples had an absent TIL pattern. Comparing the histological evaluation and the immunophenotyping data, it was observed that samples with a brisk TIL pattern had a higher frequency of CD8+ T lymphocytes (P = .05) and a lower frequency of CD4+/CD25+/FoxP3+ Tregs (P = .03), compared to the samples with nonbrisk and absent infiltrate patterns. Patients with a higher survival rate had higher TIL scores (P = .002), a brisk or nonbrisk TIL pattern (P = .001), and an increased frequency of CD8+ T lymphocytes infiltrating the tumor (P = .003). Our analysis suggests that the evaluation of TILs in canine oral melanoma is relevant to predict tumor aggressiveness and patient prognosis.

Prognostic Value of Intratumoral Collagen Quantification in Canine Oral Melanomas.

The majority of the melanocytic neoplasms are considered malignant and highly metastatic. However, a subset of the melanocytic tumors has a more favorable prognosis and the identification of precise prognostic markers for this neoplasm may be useful to guide treatment. The collagen architecture and density have been shown to correlate with tumor progression in human breast cancer and canine mast cell tumors. The purpose of the present study was to investigate the prognostic value of the intratumoral collagen index (ICI) as an indicator of postsurgical survival and its relation with other prognostic markers for canine oral melanomas (OMs). Twenty-two cases were tested for intratumoral collagen density using Masson's trichrome stain and morphometry. No differences were found between dogs regarding survival. The ICI was not correlated with proliferative activity or nuclear atypia. The results presented herein indicate that the quantity of intratumoral collagen in canine OMs is not an efficient indicator of postsurgical survival. Complementary studies about the expression and activity of enzymes that are capable of degrading extracellular matrix (ECM) components are necessary.

Plasmocitoma extramedular oral em felino doméstico / Oral extramedullary plasmocytoma in domestic cat

Plasmocitomas são geralmente incomuns em cães, representando cerca de 3% das neoplasias, e, em gatos, esse número é ainda menor, sendo consideradas raras e observadas em aproximadamente 1% dos casos. Objetiva-se com este trabalho apresentar um relato de caso de uma doença muito pouco relatada na oncologia veterinária, o plasmocitoma extramedular oral em felinos domésticos. A metodologia empregada para a construção deste trabalho deu-se por meio de: consulta a referências bibliográficas; observação e acompanhamento dos processos realizados no âmbito hospitalar, além da consulta ao prontuário médico do paciente. Embora muito descrita na literatura a utilização da cirurgia de mandibulectomia ou maxilectomia na terapia de plasmocitomas orais em cães, são escassos os relatos do emprego da técnica em gatos. Porém, é certo afirmar que a eletroquimioterapia, associada à quimioterapia antineoplásica adjuvante, promoveu uma ótima sobrevida (407 dias), sem comprometimento na qualidade de vida do paciente, mostrando que, mesmo com um tratamento menos invasivo e conservador, foi possível cuidar do paciente de maneira efetiva. Uma grande dificuldade, durante todo o processo, foi a falta de relatos científicos específicos para o plasmocitoma oral em felinos. As neoplasias orais em felinos e, principalmente, as originadas por plasmócitos precisam ser mais estudadas e relatadas, promovendo maior conhecimento técnico e científico a todos os profissionais da área.

Plasmocytomas are generally uncommon in dogs, representing about 3% of neoplasms, and in cats, this number is even lower, being considered rare and observed in approximately 1% of cases. The aim of this work is to present a case report of a disease that is rarely reported in veterinary oncology: oral extramedullary plasmacytoma in domestic cats. The methodology used for the construction of this work was given through: consultation of bibliographic references; observation and monitoring of processes performed in the hospital, in addition to consulting the patient's medical record. Although the use of mandibulectomy or maxillectomy surgery to treat oral plasmacytomas in dogs is widely described in the literature, there are few reports on the use of the technique in cats. However, it is true to say that electrochemotherapy, associated with adjuvant antineoplastic chemotherapy, promoted an excellent survival (407 days), without compromising the patient's quality of life, showing that even with a less invasive and conservative treatment it was possible to care for the patient in a way effective. A major difficulty throughout the process was the lack of specific scientific reports for oral plasmacytoma in felines. Oral neoplasms in felines and mainly those originating from plasmocytes need to be further studied and reported, promoting greater technical and scientific knowledge to all professionals in the field.

Treatment of canine oral melanoma with adjuvant chemotherapy and immunotherapy

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...

Melanoma oral amelanótico metastático com acometimento neurológico e gonadal em um cão fêmea - relato de caso / [Metastatic oral amelanotic melanoma with neurologic and gonadal involvement in a female dog - case report]

Relata-se um caso de melanoma oral disseminado em uma cadela de dois anos, com protrusão de bulbo ocular unilateral e quadro convulsivo progressivo. Os exames de imagem revelaram aumento de volume nas regiões submandibular, maxilar e cerebral, padrão nodular pulmonar e aumento das dimensões ovarianas. A citologia da massa submandibular indicou proliferação epitelial maligna, enquanto a biópsia excisional foi sugestiva de melanoma amelanótico. Na necropsia, havia uma massa gengival localmente infiltrativa e nodulações brancas nos linfonodos, nos rins, no pulmão, no cérebro e nos ovários, indicativas de metástase. O diagnóstico histopatológico consistiu de neoplasia maligna metastática indiferenciada, indicativo de melanoma amelanótico. Células caracterizadas por núcleo com cromatina espessa, múltiplos nucléolos bem evidentes, mitoses atípicas e multinucleações consistiram nos principais critérios de malignidade. No espaço peritrabecular ósseo facial, havia rara diferenciação pigmentar melanocítica, confirmada histoquimicamente pela técnica de Fontana-Massom e Giemsa. Algumas células foram positivas pela imuno-histoquímica para PNL-2 e Melan-A, e o diagnóstico de melanoma amelanótico disseminado foi firmado. A indiferenciação neoplásica marcante, com disseminação metastática multissistêmica e acometimento mútuo de sítios anatômicos pouco comuns, conjuntamente com a ampla variação dos padrões celulares, foi responsável pelo desafio diagnóstico do presente caso, ressaltando o papel decisivo da imuno-histoquímica para confirmação diagnóstica. A importância clínica deste trabalho consiste ainda em alertar a comunidade clínica e científica acerca da dificuldade diagnóstica, devendo-se considerar o melanoma amelanótico como diferencial mesmo em casos de lesões orais menos perceptíveis e/ou desprovidas de pigmentação.(AU)

A case of disseminated oral melanoma in a two year old female dog with unilateral protuberance of the eye bulb and progressive seizure is described. Imaging exams revealed increase of the submandibular, maxillary and cerebral regions, nodular pattern in lungs and increased ovarian dimensions. The cytology of the submandibular mass indicated a malignant epithelial proliferation, whereas the excisional biopsy indicated an amelanotic melanoma. At necropsy, a locally infiltrating gingival mass and white nodules in the lymph nodes, kidneys, lung, brain and ovaries were observed, indicative of metastases. Histopathological diagnosis consisted of an undifferentiated malignant metastatic neoplasm. Nucleus with coarse chromatin, prominent nucleoli, bizarre mitotic figures and multinucleated cells were the major malignant features. There was a poor melanocytic pigment differentiation in the peritrabecular space of facial bones, confirmed by Fontana-Masson and Giemsa histochemical techniques. Only a few cells were immunohistochemically positive for PNL-2 and Melan-A and the diagnosis of a disseminated amelanotic melanoma was performed. The diagnostic challenge was based on marked neoplastic undifferentiation, with multisystemic metastasis and mutual involvement of uncommon anatomic sites, associated with a large variability of cellular patterns, highlighting the decisive role of immunohistochemistry for diagnostic confirmation. Therefore, the clinical importance of this study is to warn the clinical and scientific community about the diagnostic challenge, considering the amelanotic melanoma as a differential even in cases of poorly apparent and/or nonpigmented oral lesions.(AU)

Cyclooxygenase-2 expression is associated with infiltration of inflammatory cells in oral and skin canine melanomas.

Melanoma is a fast-growing tumour in dogs and represents 7% of the total malignant neoplasms from the skin and is the most common tumour found in the oral cavity. In these tumours, high expression of cyclooxygenase-2 (COX-2) is associated with a poor prognosis. The aim of this study was to verify if the overexpression of COX-2 is related to the modulation of lymphocytes and if it is associated with the angiogenic and proliferative capacity of the melanoma. Canine melanoma samples (n = 85) were analysed by immunohistochemistry to detect the expression of S-100, Melan-A, PNL-2, COX-2, Factor VIII, Ki-67 and immune cells markers (CD3, CD4, FOXP3 and MAC387); and expression levels of MAC387, NOS and CD206 were determined by immunofluorescence. Our study showed a concurrent difference between the expression of COX-2 and inflammatory cell infiltration: Oral melanomas showed positivity for COX-2 in 34% of the cases and this expression was associated with CD3 positivity in the inflammatory infiltrate and angiogenesis; whereas cutaneous melanomas presented positivity for COX-2 in 42% of the cases and this expression was associated with positive staining for CD3, CD4, FOXP3 and MAC387. These markers are associated with inflammatory cells, angiogenesis and proliferation. Interestingly, melanomas were highly infiltrated by FOXP3+ cells, this is related to angiogenesis, whereas CD3, CD4 and MAC387 expression was only associated with cutaneous melanomas. The macrophage profile analysis showed that both oral and cutaneous melanomas with low COX-2 expression have an M1 phenoptype, whereas the cases with high COX-2 expression demonstrate a hybrid M1/M2 profile pattern. We concluded that the COX-2 is overexpressed in 42% of cutaneous melanomas and in 34% of oral melanomas, with a direct association with angiogenesis, proliferation, and intratumoral lymphocyte infiltration. We propose that COX-2 is a key regulator of immune cell infiltration and may drive tumour associated macrophage activation.

ZEB and Snail expression indicates epithelial-mesenchymal transition in canine melanoma.

Melanoma progression is associated with the epithelial-mesenchymal transition (EMT) when tumor cells reduce E-cadherin and increase N-cadherin expression resulting in an escape from the microenvironment via loss of cellular adhesion and gain of motility. Transcription factor proteins Snail and ZEB trigger EMT by repression of epithelial markers and activation of mesenchymal properties. This study evaluated E-cadherin, N-cadherin, Snail, ZEB1 and ZEB2 expression by IHC and investigated their relationship with morphological characteristics in cutaneous and oral canine melanoma. Results from melanoma cases demonstrated E-cadherin expression in 45% (9/20) of oral and 58% (22/38) of cutaneous tumors, while N-cadherin expression was observed in 95% (18/19) of oral and 92% (34/37) of cutaneous melanoma. Cytoplasmic and nuclear N-cadherin expression was positively correlated with ZEB1 expression, while the cell membrane N-cadherin expression was positively correlated with ZEB2. In addition, an increase in nuclear N-cadherin expression was associated with reduced Snail expression in cutaneous melanoma and an increase in Snail expression in oral melanoma, indicating that the correlation between N-cadherin and Snail expression is coincident with tumor location. Our data suggest that ZEB family protein is associated with N-cadherin translocation from cell membrane to the cytoplasm and nuclei, and may act as important transcription factors of EMT regulation in canine melanoma.

Ablação de neoplasia no vestíbulo da cavidade oral de equino / Neoplasia ablation in the equine oral cavity vestibule

Background: Oral squamous cell carcinoma is responsible for more than 90% of head and neck neoplasms in humans.Multiple factors are associated with the development of squamous cell carcinomas in humans and animals, such as prolonged exposure to ultraviolet light, lack of pigment in the epidermis, or sparse hair coverage. In horses, oral forms arerare and represent 7% of cases, but sarcoids are the main type of oral neoplasia. In the present case, due to the location andanatomical dimensions of the oral vestibule, it was necessary to adapt it to the natural tumor excision, a fact that aimedto describe this report.Case: One Arabian 2- year-old male horse, treated at the Veterinary Hospital of the Santa Cruz State University (UESC),with signs of severe mouth bleeding and halitosis. Clinical inspection of the face showed elevation in the masseter regionand left mandible branch. Clinical examination of the oral cavity revealed soft tissue tumor extending from tooth 308(PM-1, lower left) to 311 (M-3, lower left) and on the buccal surface of the left mandible branch. Radiographic examination revealed no invasion of bone tissue by the tumor. Biopsy material was collected. The histopathological report was ofneoplastic cell proliferation, frequent mitoses, binucleate cells and extensive ulceration area associated with neutrophilicinflammatory infiltrate, indicative of squamous cell carcinoma. The animal was referred to the Surgical Sector who, afterevaluation of the animal, opted for the ablation of the neoplasia. Pre-anesthesia performed with intravenous detomidine30 µg/kg, anesthesia with regional mandibular nerve block with 20 mL of 2% lidocaine and maintenance with continuousinfusion of detoxid 0.5 µg/kg/ min. Contention for the operative act in the quadrupedal...(AU)

Electrochemotherapy in treatment of canine oral malignant melanoma and factors influencing treatment outcome.

Background Oral malignant melanoma is the most common, but aggressive oral cancer in dogs with poor prognosis. Electrochemotherapy (ECT) has therapeutic potential in such tumors as effective local treatment. Therefore, the aim of this prospective clinical study was to evaluate treatment effectiveness of ECT in as first line treatment for canine oral malignant melanoma, and search for factors influencing treatment outcome. Methods Sixty-seven canines with primary oral malignant melanoma, non-candidates for first-line therapy, were enrolled. All dogs received ECT and follow-up exams for the span of two years. Results Based on RECIST criteria, the objective response rate was 100%, 89.5%, 57.7%, and 36.4%, in stage I, II, III and IV, respectively. Only patients in stage I, II and III with partial or complete response improved their quality of life. The median time to progression was 11, 7, 4 and 4 months, and median survival time after the treatment was 16.5, 9.0, 7.5 and 4.5 months, for patients in stage I, II, III and IV, respectively. Significantly better was local response in stage I and II disease (p = 0.0013), without the bone involvement (p = 0.043) Conclusions Electrochemotherapy is effective local treatment of oral canine malignant melanoma when no alternative treatment is available. Better response is expected in stage I and II patients with tumors without bone involvement.

Inhibitory Effects of a Reengineered Anthrax Toxin on Canine Oral Mucosal Melanomas.

Canine oral mucosal melanomas (OMM) are the most common oral malignancy in dogs and few treatments are available. Thus, new treatment modalities are needed for this disease. Bacillus anthracis (anthrax) toxin has been reengineered to target tumor cells that express urokinase plasminogen activator (uPA) and metalloproteinases (MMP-2), and has shown antineoplastic effects both, in vitro and in vivo. This study aimed to evaluate the effects of a reengineered anthrax toxin on canine OMM. Five dogs bearing OMM without lung metastasis were included in the clinical study. Tumor tissue was analyzed by immunohistochemistry for expression of uPA, uPA receptor, MMP-2, MT1-MMP and TIMP-2. Animals received either three or six intratumoral injections of the reengineered anthrax toxin prior to surgical tumor excision. OMM samples from the five dogs were positive for all antibodies. After intratumoral treatment, all dogs showed stable disease according to the canine Response Evaluation Criteria in Solid Tumors (cRECIST), and tumors had decreased bleeding. Histopathology has shown necrosis of tumor cells and blood vessel walls after treatment. No significant systemic side effects were noted. In conclusion, the reengineered anthrax toxin exerted inhibitory effects when administered intratumorally, and systemic administration of this toxin is a promising therapy for canine OMM.

Diverse roles of epidermal growth factors receptors in oral and cutaneous canine melanomas.

BACKGROUND: The epidermal growth factor receptors participate in the physiological processes such as regulation of morphogenesis, proliferation and cell migration, but when overexpressed or overactivated they may play an important role in neoplastic progression. Melanoma is the most aggressive skin neoplasm and is characterized by elevated invasion and low survival rates in both humans and dogs. In human melanomas the overexpression of EGFR, HER3 or HER4 is associated with poor prognosis. In canine melanomas the epidermal growth factor receptors expression has not been evaluated. Therefore, this study evaluated the expression of epidermal growth factor receptors by immunohistochemistry and investigated their relationship with morphological characteristics and proliferative indices in cutaneous and oral canine melanoma. RESULTS: In cutaneous melanoma an increased proliferative index was associated with increased cytoplasmic HER4 and reduced EGFR and HER3 protein expression. In oral melanomas, membranous HER2 protein expression correlated with occurrence of emboli, but ERBB2 gene amplification wasn't observed. CONCLUSION: Thus, our work evidenced the relationship between HER4 and the stimulus to cell proliferation in cutaneous melanomas, in addition to the relationship between HER2 and the occurrence of emboli in oral melanomas.

Ablação de neoplasia no vestíbulo da cavidade oral de equino / Neoplasia ablation in the equine oral cavity vestibule

Background: Oral squamous cell carcinoma is responsible for more than 90% of head and neck neoplasms in humans.Multiple factors are associated with the development of squamous cell carcinomas in humans and animals, such as prolonged exposure to ultraviolet light, lack of pigment in the epidermis, or sparse hair coverage. In horses, oral forms arerare and represent 7% of cases, but sarcoids are the main type of oral neoplasia. In the present case, due to the location andanatomical dimensions of the oral vestibule, it was necessary to adapt it to the natural tumor excision, a fact that aimedto describe this report.Case: One Arabian 2- year-old male horse, treated at the Veterinary Hospital of the Santa Cruz State University (UESC),with signs of severe mouth bleeding and halitosis. Clinical inspection of the face showed elevation in the masseter regionand left mandible branch. Clinical examination of the oral cavity revealed soft tissue tumor extending from tooth 308(PM-1, lower left) to 311 (M-3, lower left) and on the buccal surface of the left mandible branch. Radiographic examination revealed no invasion of bone tissue by the tumor. Biopsy material was collected. The histopathological report was ofneoplastic cell proliferation, frequent mitoses, binucleate cells and extensive ulceration area associated with neutrophilicinflammatory infiltrate, indicative of squamous cell carcinoma. The animal was referred to the Surgical Sector who, afterevaluation of the animal, opted for the ablation of the neoplasia. Pre-anesthesia performed with intravenous detomidine30 µg/kg, anesthesia with regional mandibular nerve block with 20 mL of 2% lidocaine and maintenance with continuousinfusion of detoxid 0.5 µg/kg/ min. Contention for the operative act in the quadrupedal...

Occurrence of oral cavity neoplasms in canines attended at the oncology service of the Federal Rural University of Rio de Janeiro (2011 to 2017) / Ocorrência de neoplasias em cavidade oral em caninos atendidos no serviço de oncologia da Universidade Federal Rural do Rio de Janeiro (2011 a2017)

The oral cavity is among the main sites of neoplasia, both benign and malignant. Those with characteristics of malignancy have an unfavorable prognosis due to their biological behavior and diagnostic and therapeutic difficulties. Epidemiological data are important to profile the affected population and establish an early treatment strategy, optimizing treatment and increasing the chances of cure and quality of life. The objective of this study was to present the clinical epidemiological aspects of dogs treated with neoplasms in the oral cavity at the Oncology Service of the Veterinary Hospital of the Federal Rural University of Rio de Janeiro between the years 2011 and 2017 through a retrospective study of all the medical records of the respective service. The epidemiological data extracted from the archives showed that out of 2832 cases of neoplasms treated in the oncology sector over a 7-year interval (2011 to 2017), 176 animals (6.21%) were affected by oral cavity neoplasms. The dogs without a defined breed were the most affected, the main site affected was the maxilla and melanoma was the most prevalent neoplasm.

A cavidade oral figura entre os principais sítios de acometimento por neoplasias, tanto benignas quanto malignas. Aquelas que possuem características de malignidade têm o prognóstico desfavorável pelo seu comportamento biológico e pela dificuldade diagnóstica e terapêutica. Os dados epidemiológicos são importantes para se traçar um perfil da população acometida e estabelecer uma estratégia de tratamento precoce otimizando o tratamento e aumentando as chances de cura e a qualidade de vida. O objetivo deste trabalho foi apresentar os aspectos clínicos epidemiológicos dos cães atendidos com neoplasias na cavidade oral no Serviço de Oncologia do Hospital Veterinário da Universidade Federal Rural do Rio de Janeiro entre os anos de 2011 e 2017 por meio de um estudo retrospectivo de todos os prontuários do referido serviço. Os dados epidemiológicos extraídos dos arquivos evidenciaram que dos 2832 casos de neoplasias atendidos no setor de oncologia em um intervalo de 7 anos (2011 a 2017), as neoplasias da cavidade oral acometeram 176 animais (6,21%). Os cães sem raça definida foram os mais acometidos, o principal local acometido foi a maxila e o melanoma foi a neoplasia mais prevalente.

Occurrence of oral cavity neoplasms in canines attended at the oncology service of the Federal Rural University of Rio de Janeiro (2011 to 2017) / Ocorrência de neoplasias em cavidade oral em caninos atendidos no serviço de oncologia da Universidade Federal Rural do Rio de Janeiro (2011 a2017)

The oral cavity is among the main sites of neoplasia, both benign and malignant. Those with characteristics of malignancy have an unfavorable prognosis due to their biological behavior and diagnostic and therapeutic difficulties. Epidemiological data are important to profile the affected population and establish an early treatment strategy, optimizing treatment and increasing the chances of cure and quality of life. The objective of this study was to present the clinical epidemiological aspects of dogs treated with neoplasms in the oral cavity at the Oncology Service of the Veterinary Hospital of the Federal Rural University of Rio de Janeiro between the years 2011 and 2017 through a retrospective study of all the medical records of the respective service. The epidemiological data extracted from the archives showed that out of 2832 cases of neoplasms treated in the oncology sector over a 7-year interval (2011 to 2017), 176 animals (6.21%) were affected by oral cavity neoplasms. The dogs without a defined breed were the most affected, the main site affected was the maxilla and melanoma was the most prevalent neoplasm.(AU)

A cavidade oral figura entre os principais sítios de acometimento por neoplasias, tanto benignas quanto malignas. Aquelas que possuem características de malignidade têm o prognóstico desfavorável pelo seu comportamento biológico e pela dificuldade diagnóstica e terapêutica. Os dados epidemiológicos são importantes para se traçar um perfil da população acometida e estabelecer uma estratégia de tratamento precoce otimizando o tratamento e aumentando as chances de cura e a qualidade de vida. O objetivo deste trabalho foi apresentar os aspectos clínicos epidemiológicos dos cães atendidos com neoplasias na cavidade oral no Serviço de Oncologia do Hospital Veterinário da Universidade Federal Rural do Rio de Janeiro entre os anos de 2011 e 2017 por meio de um estudo retrospectivo de todos os prontuários do referido serviço. Os dados epidemiológicos extraídos dos arquivos evidenciaram que dos 2832 casos de neoplasias atendidos no setor de oncologia em um intervalo de 7 anos (2011 a 2017), as neoplasias da cavidade oral acometeram 176 animais (6,21%). Os cães sem raça definida foram os mais acometidos, o principal local acometido foi a maxila e o melanoma foi a neoplasia mais prevalente.(AU)