Primary pulmonary chondrosarcoma in a bitch

Background: Primary lung neoplasms are uncommon in veterinary medicine, and when they develop, they are more frequently observed to be of epithelial origin. Although chondrosarcomas are the second most diagnosed type of neoplasm in dogs at skeletal sites, their development in extraskeletal tissues, including the spleen, aorta, heart, tongue, peritoneum, and lungs, corresponds to approximately only 1% of cases. Therefore, the occurrence of primary pulmonary chondrosarcoma is considered very rare in domestic animals. Considering the rare occurrence and scarcity of data regarding its development, the present report describes the clinical and pathological aspects of a case of primary pulmonary chondrosarcoma in a bitch. Case: A 8-year-old mixed-breed bitch, weighing 14.2 kg, was examined at one private veterinary clinic with the principal complaint of prolonged respiratory distress and resistance to exercise. Clinical evaluation revealed tachypnea with expiratory dyspnea due to intense pleural effusion, tachycardia, and diffusely pale mucous membranes. Thoracocentesis was performed with drainage of 1000 mL of modified transudate, and fluid cytology, blood count, and chest radiography were performed. Cytological analysis of the thoracic fluid did not identify neoplastic cells, the blood count showed intense regenerative anemia, and the radiograph showed an extensive area of consolidation in the left caudal lung lobe, compatible with neoplasia. The results of the tests performed, in addition to the evolution of the clinical picture and the impossibility of performing the indicated surgical intervention, culminated in the patient's unfavorable prognosis, followed by euthanasia, necropsy, and histopathological evaluation of the collected material. Necropsy revealed a white neoplastic formation with reddish areas and firm consistency that diffused into the parenchyma of the left caudal lung lobe with invasion of the rib cage, fracture of the fifth and sixth left ribs, diaphragmatic metastasis, intense hydrothorax, and moderate hydroperitoneum. Microscopically, in the histological sections of the lung and diaphragm, poorly differentiated mesenchymal cells with moderate anisocytosis and anisokaryosis and interspersed with them, moderately differentiated chondrocytes surrounded by chondroid matrix, moderate anisocytosis and anisokaryosis, and a low mitotic index culminated in the diagnosis of primary pulmonary mesenchymal chondrosarcoma. Discussion: Malignant epithelial neoplasms were suspected; however, the histopathological features observed were compatible with primary pulmonary chondrosarcoma. The characteristics of the fluid collected through thoracentesis led to its classification as a modified transudate, which is often associated with neoplastic and hemorrhagic processes; both alterations were present in this case. The diagnosis of primary pulmonary chondrosarcoma was established based on the histopathological findings since the cell type and distribution observed in the present case were compatible with the typical pattern observed in extraskeletal chondrosarcomas. An unfavorable prognosis is common in cases of primary or metastatic lung neoplasm since, in most cases, the condition is identified in the advanced stages of the disease, making therapeutic management challenging. Given the increase in the number of dog deaths due to neoplasms in recent years, this case report may contribute to a better understanding of the biological behavior of pulmonary chondrosarcoma and assist in the choice of treatment to be adopted when required.

Molecular docking, ADMET and molecular dynamics simulation revealed metralindole as a multitargeted inhibitor for division kinases / Ancoragem molecular, ADMET e simulação de dinâmica molecular revelaram o metralindol como inibidor multialvo para divisão quinases

Lung cancer is the most common type of cancer in the world, and alone, in 2020, almost 2.21 million new cases were diagnosed, with 1.80 million deaths, and are increasing daily. Non-small cell lung (NSCLC) is the primary type of lung cancer, predominantly forms around 80% of cases compared to small cell carcinoma, and about 75% of patients are already in an advanced state when diagnosed. Despite notable advances in early diagnosis and treatment, the five-year survival rate for NSCLC is not encouraging. Therefore, it is crucial to investigate the molecular causes of non-small cell lung cancer to create more efficient therapeutic approaches. Lung cancer showed a more significant and persistent binding affinity and energy landscape with the target CDK2 staurosporine and FGF receptor-1. In this study, we have picked two essential target proteins, human cyclin-dependent kinase-2 and Human Protein Kinase CK2 Holoenzyme and screened the entire prepared DrugBank prepared library of 1,55,888 compounds and identified 2-(2-methyl-5-nitroimidazole-1-yl) ethanol (Metralindole) as a major inhibitor. Metralindole has displayed high docking scores of -5.159 Kcal/mol and -5.99 Kcal/mol with good hydrogen bonding and other bonding topologies such as van der Waals force, and ADMET results shown excellent bioavailability, outstanding solubility, no side effects, and toxicity. The molecular dynamics simulation for 100ns in a water medium confirmed the compound's stability and interaction pattern with the lowest deviation and fluctuations. Our in-silico study suggests Metralindole, an experimental compound, can effectively cure lung cancer. Further, the experimental validation of the compound is a must before any prescription.

O câncer de pulmão é o tipo de câncer mais comum no mundo, e, apenas em 2020, foram diagnosticados quase 2,21 milhões de novos casos, com 1,8 milhão de óbitos, e isso vem aumentando diariamente. O câncer de pulmão de células não pequenas (CPCNP) é o tipo primário de câncer de pulmão, forma que predomina em cerca de 80% dos casos em comparação com o carcinoma de pequenas células, e cerca de 75% dos pacientes já estão em estado avançado quando diagnosticados. Apesar dos avanços notáveis no diagnóstico e tratamento precoces, a taxa de sobrevida em cinco anos para CPCNP não é animadora. Portanto, é crucial investigar as causas moleculares do CPCNP para criar abordagens terapêuticas mais eficientes. O câncer de pulmão mostrou uma afinidade de ligação e perfil energético mais significativos e persistentes com a estaurosporina CDK2 alvo e o receptor-1 de FGF. Neste estudo, escolhemos duas proteínas-alvo essenciais, a quinase dependente de ciclina humana-2 e a holoenzima CK2 da proteína quinase humana, examinamos toda a biblioteca preparada pelo DrugBank de 1,55,888 compostos e identificamos 2-(2-metil-5-nitroimidazol-1-il) etanol (metralindol) como inibidor principal. O metralindol apresentou altas pontuações de ancoragem de -5,159 Kcal/mol e -5,99 Kcal/mol, com boas ligações de hidrogênio e outras topologias de ligação, como a força de Van der Waals, e os resultados do ADMET mostraram excelente biodisponibilidade e solubilidade, sem efeitos colaterais e toxicidade. A simulação de dinâmica molecular para 100ns em meio aquoso confirmou a estabilidade e o padrão de interação do composto com os menores desvios e flutuações. Nosso estudo in silico sugere que o metralindol, um composto experimental, pode efetivamente curar o câncer de pulmão. Além disso, a validação experimental do composto é obrigatória antes de qualquer prescrição.

Carcinoma hepatocelular metastático em Amazona aestiva / Metastatic hepatocellular carcinoma in Amazona aestiva

Background: Hepatocellular carcinoma is a primary malignant tumor of the liver tissue and its occurrence in birds is considered rare. The tumor can occur as a single mass leading to hepatomegaly, or as multiple nodules in the liver. In animals of the genus Amazona, only 1 case of metastatic hepatocellular carcinoma has been reported in the United States, therefore, little is known about its epidemiology and clinicopathological aspects in these species. In this context, the aim of this work was to describe a case of metastatic hepatocellular carcinoma in an Amazona aestiva. Case: A blue-fronted amazon parrot (Amazona aestiva) was referred to necropsy after being found dead in its enclosure. On examination, it presented cachectic body score. Examination of the coelomic cavity, revealed a serous translucent fluid and adhesions between the liver and peritoneum.A red mass restricted to the right hepatic lobe and raised to the capsular surface, interspersed with whitish and dark red multifocal areas was observed. When cut, this mass was soft, protruding, multilobulated, whitish and with a friable reddish center. Additionally, on the dorsal surface of the left lung lobe, there was a rounded, well defined, whitish, and soft nodule. Microscopically, partial replacement of the hepatic parenchyma was observed by neoplastic proliferation of cuboidal epithelial cells, organized in mantle and supported by a scarce fibrovascular stroma. Cells have large, eosinophilic, well-delimited cytoplasm, with a central, oval nucleus, loose chromatin, and evident nucleolus. Moderate pleomorphism was characterized by anisocytosis, anisokaryosis, and aberrant nuclei. In the lung, a focally extensive mass with a pattern similar to that seen in the liver was observed. In the kidney, multifocal neoplastic emboli were noted. Liver immunohistochemistry was performed. Positive and negative controls were used to validate the reaction; however, there was no immunolabelling for the evaluated antibodies. Discussion: The histopathological characteristics observed in this study favored the diagnosis of hepatocellular carcinoma (HCC) with metastasis to kidney and lung. Primary liver tumors are rare in wild birds. In ducks, experimental studies have pointed aflatoxins and the duck hepatitis B virus as oncogenic agents, however, in birds of the genus Amazona, there are no studies that evaluate predisposing factors to the development of liver carcinoma. Macroscopically, hepatocellular carcinoma may present in massive, nodular or diffuse forms. In birds, the right lobe is the largest, which may suggest that this lobe is more prone to the development of HCC, as seen in the present case. The solid form, similar to that observed in this report, seems to be more commonly observed, as seen in the wild bird reports consulted. Metastases most often spread hematogenous, and in the present report there was metastasis to kidneys and lungs, which is a common feature for this neoplasm. In the present case, there was no labeling by any of the antibodies, perhaps because of their aggressiveness, associated with autolytic factors that prevent the labeling of antibodies, in addition to the specificity in the antibodyantigen relationship. This tumor must be differentiated from other liver tumors such as cholangiocarcinoma, and also the well-differentiated hepatocellular adenoma, in addition to non-neoplastic conditions. HCC should be considered as a differential diagnosis for Amazona aestiva found dead in the enclosure without previous clinical signs. This neoplasm is rare in Amazon parrots and reports should be encouraged in order to contribute to the understanding of the epidemiological and clinicopathological aspects of the tumor.

Hiperplasia fibroepitelial mamária em um gato macho: relato de caso / Mammary fibroepithelial hyperplasia in a male cat: case report

As neoplasias mamárias representam a terceira neoplasia mais comum em gatas, enquanto nos machos a incidência é rara. Esse trabalho relata o caso de um gato macho, não castrado, atendido no Hospital Veterinário da Universidade Estadual do Ceará, com uma neoformação mamária. O diagnóstico inicial, obtido por meio de punção aspirativa por agulha fina, sugeriu a presença de carcinoma mamário. Exames de imagem como a radiografia torácica e a ultrassonografia abdominal não evidenciaram a presença de metástase no parênquima pulmonar e nos órgãos abdominais, respectivamente. O tratamento instituído foi a remoção cirúrgica da neoformação, pela técnica de mastectomia parcial bilateral. O exame histopatológico da massa evidenciou uma hiperplasia fibroepitelial. Diante disso, conclui-se que, apesar de raras, as neoformações mamárias em gatos do sexo masculino podem ocorrer, devendo, dessa forma, compor parte da lista de diagnósticos diferenciais para aumentos de volume na região ventral desses animais.(AU)

Mammary neoplasms represent the third most common neoplasm in queens, while in tomcats the incidence is rare. This study reports the case of a tomcat, not neutered, treated at the Veterinary Hospital of the State University of Ceará, with a mammary neoformation. The initial diagnosis, obtained through aspiration cytology, suggested the presence of mammary carcinoma. Imaging tests such as thoracic radiography and abdominal ultrasound, did not show the presence of metastasis in the lung parenchyma and abdominal organs, respectively. The chosen treatment was the surgical removal of the neoformation, using the bilateral partial mastectomy technique. Histopathological examination of the mass showed a mammary fibroepithelial hyperplasia. Therefore, it is concluded that, although rare, mammary neoformations in male cats can occur, thus, it should be part of the list of differential diagnoses for increases in volume in the ventral region of these animals.(AU)

Adenocarcinoma pancreático em um gato / Pancreatic adenocarcinoma in a cat

Background: Despite being rare in domestic animals, pancreatic adenocarcinoma is the most common malignant tumor of the feline pancreas. Due non-specificity of clinical signs in cats and the late diagnosis of the neoplasm, it is necessary to understand this disease better, to contribute for the knowledge of its early recognition and treatment. Thus, this study aims to report a case of metastatic pancreatic ductal adenocarcinoma in a cat, focusing on the main clinical aspects, diagnosis, and prognosis of this disease, in addition to the description of the presentation of peritoneal carcinomatosis. Case: A 14-year-old male neutered mixed breed cat, was referred to the Feline Medicine Service (MedFel) of the Hospital de Clínicas Veterinárias (HCV) - Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, with a history of hyporexia, constipation and increased abdominal volume for 3 days, besides mild difficulty in locomotion and progressive weight loss in the last 6 months. On the physical examination, the patient was alert, with a body condition score of 6/9; muscle condition score 1/4 and moderate dehydration of 7%. Popliteal lymph nodes were enlarged, and abdominal distension was evident. Around 200 mL of a slightly cloudy, straw-yellow liquid were drained from the abdominal cavity. After draining the fluid, a new abdominal palpation was performed, and there were fecal retention and a palpable mass in the right hypogastric region. The result of the cytological analysis of the fluid was consistent with a protein-rich transudate, suggesting neoplastic effusion of epithelial origin. Hematological and biochemical changes included leukocytosis due to neutrophilia, monocytosis, lymphopenia, thrombocytosis and azotemia. On abdominal ultrasound, the patient had free fluid in the abdominal cavity, and the gallbladder had discreet of biliary sludge. The intestines showed some corrugated segments with other segments lacking definition of its layers, and without peristaltic movements, suggesting intestinal neoplasia. Pancreas and adrenals were not visualized. On the chest X-ray, moderate opacification of lung fields with a diffuse interstitial pattern was observed, suggesting lung metastasis. The patient presented an acute worsening of the clinical condition and the owner requested euthanasia. The patient was referred for necropsy and based on the macroscopic and microscopic changes, the post-mortem diagnosis was metastatic pancreatic ductal adenocarcinoma with peritoneal carcinomatosis. Discussion: The clinical presentation of cats with exocrine pancreatic neoplasia is nonspecific, as clinical signs are common to several diseases, such as anorexia, vomiting, abdominal pain, weight loss with normal appetite, jaundice, depression, and lethargy. Complementary blood tests also do not provide data that could lead to the suspicion of pancreatic neoplastic disease. In the present case, the diagnosis of metastatic pancreatic ductal adenocarcinoma with peritoneal carcinomatosis was only possible post mortem. The pancreas is a difficult organ to assess adequately using most diagnostic imaging methods, so histopathology is still the method of choice for differentiating pancreatic tissue comorbidities. Therefore, exploratory laparotomy should be instituted to provide tissue samples from the pancreas and its metastases for histopathological diagnosis, whenever ultrasound or other imaging methods indicate suspicious abdominal changes. The literature reports that less than 10% of affected cats treated with complete surgical removal of the mass and chemotherapy alone will survive more than a year, and the average time for untreated cats is only 6 days. The prognosis of this disease is bad and most cats are euthanized, due to rapid clinical worsening. Therefore, diagnosis is essential to determine an adequate prognosis in advanced cases and to support therapeutic decisions or euthanasia.

Adenocarcinoma de saco anal com metástase vertebro-medular em um Cocker Spaniel / Anal sac adenocarcinoma with vertebromedullary metastasis in a Cocker Spaniel

Background: Several neoplasms can affect the perianal region, being the hepatic adenoma and the anal sac adenocarcinoma (ASAC), which is considered the most frequent. The ASAC is a malignant neoplasm originating from the secretory epithelium of the perianal apocrine glands and is rarely seen in veterinary medicine. The ASAC occurs mainly in adult to elderly canines with high metastasis rates. Patients may be asymptomatic or manifest discomfort and behavioral changes. In the presence of metastasis, the most frequent clinical signs are inappetence, coughing, dyspnea, and colorectal obstruction. Given this scenario, this paper aims to describe the clinical presentation, diagnostic examination, and necropsy findings of a Cocker Spaniel with ASAC and metastasis in the vertebral body, spinal cord, and cauda equina. Case: A 8-year-old neutered male Cocker Spaniel (12 kg of body mass) with a clinical history of non-ambulatory paraparesis was evaluated. The patient also presented tenesmus, difficulty to defecate, and the presence of nodules in the anal sac area. On the neurological examination, asymmetrical changes compatible with injury between L4-S3 were found. A complete blood count, serum biochemistry, and imaging exams such as plain radiography, abdominal ultrasonography (US), and magnetic resonance imaging (MRI) were requested. Blood count revealed anemia and neutrophilic leukocytosis and hypercalcemia. The liver showed increased echogenicity and thickened pancreas in the abdominal US scan. A slightly heterogeneous, vascularized mass with irregular borders was identified in the topographic region of the sublumbar lymph nodes; MRI images demonstrated an expansile formation in the ventral region of the lumbosacral spine, corresponding to the sublumbar lymph nodes and interruption of the cerebrospinal fluid at L5, suggestive of compression of the spinal cord and cauda equina. A presumptive diagnosis of perianal neoplasm with metastasis was made based on the complementary exams. The dog was referred to necropsy, which revealed a 4 cm tumor in the perianal region that invaded the pelvic canal. Multifocal nodules were present on the lung surface, liver, and kidneys, suggesting metastasis. On the cross-section of the spine, one could note the presence of the tumor in the vertebral bodies, spinal cord, and cauda equina from L5 to S3. Even with histopathological evaluation of the tumor, only the immunohistochemical analysis allowed us to confirm the anal sac adenocarcinoma. Discussion: Adenomas and carcinomas are perianal gland neoplasms common in adult and elderly male dogs; the Cocker Spaniel breed is among the most affected. The clinical signs presented by the patient, such as tenesmus and difficulty in adopting the posture of defecation, are common, although neurological changes are rare. As for metastasis, carcinomas of the perianal region present high chances of metastasis to organs including the liver, kidneys, and lungs, both lymphatically and hematogenously, but few studies have related these factors to neurological alterations due to metastasis. We concluded that metastases from carcinomas to the spine must be considered a possible differential diagnosis in cases of patients presenting clinical signs that are compatible with spinal cord compression and a history of previous neoplasm.

Mesotelioma pleural em mediastino em uma cadela - remoção com esternotomia mediana / Mediastinal mesothelioma in a bitch - removal with median sternotomy

Background: Malignant pleural mesothelioma (MPM) is a neoplasm with low incidence in small animals, and the possible causes are poorly elucidated but may be related to contact with asbestos. In the thoracic cavity, MMP can be localized or generalized to all cavity structures, and its clinical signs depend on this localization. Although some alternative therapies are being discussed, few studies are conclusive, with surgical intervention as the leading therapeutic option. Given this context, this report aimed to describe a case of MMP located in the mediastinum of a bitch treated with radical excision through mediated sternotomy. Case: A 7-year-old bitch of the Shar-pei breed was referred for care due to progressive weight loss and intense dyspnea. During the physical examination, dyspnea and muffled lung sounds were noted. The patient underwent hemodialysis, which showed neutrophilic leukocytosis. An abdominal ultrasound was also performed and revealed mild abdominal effusion, and chest radiography revealed an extensive tumor covering the entire chest cavity. Thoracocentesis was performed, and the material analyzed was a malignant exudate; the patient was referred to median sternotomy for exploratory purposes, and afterward, total macroscopic extirpation of the tumor was performed. A sample was sent for histopathology, and malignant mesothelioma was confirmed. The patient was discharged after 8 days of hospitalization with home treatment and did not return to the hospital. Upon contacting the guardian, we were informed that the animal had died 154 days after the procedure due to unknown causes. Discussion: Malignant pleural mesothelioma affects humans and animals; it is associated with the risk factor of contact with asbestos and the use of flea antiparasitic drugs. In small animals, its incidence is rare, albeit mesotheliomas have been reported in wild and large animals. The clinical signs are related to the location of the neoplasm. When it is located in the thoracic region, dyspnea, muffled lung sounds, cyanosis, and pleural effusion are observed in most cases. Diagnosis is usually late and incidental, although some tests, such as ultrasonography, magnetic resonance imaging, tomography, radiography, and needle biopsy, can help in the diagnosis. Histopathology is the exam of choice for definitive diagnosis, as it helps one observe the proliferation of neoplastic mesothelial cells, atypical mitosis figures, and marked cellular pleomorphism. Many therapeutic options have been discussed, including chemotherapy, immunotherapy, and anti-tumor immunization, although there is little scientific proof of their efficacy in animals. The current treatment of choice is tumor excision by surgical procedure with a palliative objective since the prognosis of the disease is unfavorable. Minimally invasive video surgery has been gaining more and more space in veterinary medicine and has proven successful in numerous cases of thoracic masses. In the present report, we chose to perform median sternotomy for total excision due to the extension of the mass that occupied the thoracic cavity practically in its entirety. Further research should be conducted to help in palliative treatments and increase the survival of patients with mesotheliomas, given that most studies are done in humans and not animals. We conclude that median sternotomy is still the therapeutic option of choice for the palliative treatment of patients with extensive thoracic pleural mesotheliomas.

Epididymal primary mast cell tumor in a dog

Background: In the literature, there are a few descriptions of epididymis neoplasia in domestic animals, especially considering primary tumors. In the few reports found in literature, the lesions were a consequence of the invasion of testicular or paratesticular neoplasia, as a papillar carcinoma in a dog's and a bull's epididymis, and mesenchymal tumors - fibrome/ fibrosarcoma, leiomyoma/leiosarcome. On the other hand, mast cell tumors are the second most prevalent neoplasia in dogs in Brazil, affecting especially the skin. The aim of this report is to describe for the first time a low malignancy mast cell tumor in a mixed-breed dog's epididymis, without metastasis or recurrence in a 2-year follow-up period. Case: A 10-year-old male mixed-breed dog was presented for pre-surgical evaluation for elective orchiectomy. In the physical examination, an increase in the volume of approximately 2 cm with an irregular appearance was identified on palpation in the cranial pole of the left testis. In the trans surgical period, an increase in testicular volume (4 cm long x 2 cm wide) was observed, with a firm consistency in the region of the vas deferens with macroscopic changes in the region. The testis was sectioned, and the fragments were sent for histopathological evaluation in 10% buffered formaldehyde. There was a fairly cellular circumscribed neoplastic infiltrate, distributed in a sheet and separated by fibrovascular stroma, and rounded neoplastic cells with a moderate amount of basophilic cytoplasmic granulation, and discrete anisocytosis and anisokaryosis. The nuclei were rounded with vesicular chromatin with 1 or 2 distinct nucleoli. No mitosis figures were observed in 10 high power fields (400x). Few eosinophils were distributed throughout the neoplastic cell population. Immunohistochemistry demonstrated immunostaining for KIT protein with perimembranous staining in 95% of neoplastic mast cells, giving a KIT 1 pattern. There was no positive nuclear staining for Ki67 in any cell of the histological sections examined. A grade II mast cell tumor (low grade of malignancy) was diagnosed. After diagnosis, the animal underwent radiographic evaluation of the chest and abdominal ultrasound, and a new physical inspection in search of nodules, plaques, skin lesions, or subcutaneous masses. There were no metastases in the thorax and abdominal cavity, nor physical alterations, and it can be inferred that the epididymis was the primary site of the mast cell tumor. After 2 years of orchiectomy, there were no recurrences, and no chemotherapy treatment was performed. Discussion: Extracutaneous mast cell tumors are uncommon in animals, but have been reported in oral and nasal mucosa, nasopharynx, larynx, trachea, intestine, visceral lymph nodes, spleen, liver, spinal cord, intestine, ureter, conjunctiva, lung and more recently in tear gland of the third eyelid. However, in the authors' assessment, this is the first description of mast cell tumor in the epididymis in dogs. The diagnosis was established by histopathological examination, which revealed a grade II epididymal mast cell tumor and immunohistochemical evaluation (KIT and Ki-67) as being of low aggressiveness. The diagnosis of a primary tumor was confirmed since the staging was established after the histopathological diagnosis, involving chest radiography, abdominal ultrasound, cutaneous evaluation in search of nodules, plaques, cutaneous and subcutaneous lesions, and did not reveal other abnormalities or metastases not identified in the preoperative evaluation. In addition, immunostaining with KIT and Ki-67 reaffirmed the low degree of malignancy and the potential for metastases, which can be observed by the asymptomatic follow-up of the patient 2 years after the surgical excision.

Síndrome da feminização em cão com sertolioma / Feminization syndrome in a dog with Sertoli cell tumor

Background: The uncontrolled multiplication of Sertoli cells causes Sertoli cell tumor or Sertolioma. Because of this, the level of estrogen in the bloodstream increases rapidly and approximately 25% of dogs with this tumor develop feminization syndrome. Testicular neoplasms are more common in dogs than cats, and are often found in elderly patients. This work aims to describe the clinical signs of the feminization syndrome and the treatment instituted in a canine diagnosed with sertolioma. Case: A 18-year-old male canine, 19.5 kg of body mass, with an increase in testicular volume for about 2 years, was treated at the University Veterinary Hospital. On clinical examination, a matte and brittle coat, alopecia on the hind limbs and gynecomastia were observed. Also noted, non-harmonious aspect of the scrotum, pendular foreskin, atrophied right testicle and hyperplastic left, scrotal hyperthermia and absence of pain. In addition, as a result of the hyperestrogenism resulting from the neoplasm, the paraneoplastic syndrome of feminization, the patient also presented galactorrhea, pendular foreskin, atrophy of the penis and the contralateral testicle, dermatopathies, such as bilateral symmetrical alopecia of the flanks, easily removable hair and variable hyperpigmentation. Rectal body temperature of 38.6°C, clear lung auscultation and muffled cardiac auscultation. The results of laboratory tests showed changes such as thrombocytopenia, platelet counts below the reference levels, platelet count of 163,000/uL. There were no alterations that represented metastases in the imaging exams, such as in the chest X-ray in three incidences and in the abdominal ultrasonography. Then, we opted for the surgical procedure of orchiectomy, with the traditional technique of three clamps, associated with total ablation of the scrotum. Samples were sent to the histopathology laboratory and the diagnosis of sertolioma was confirmed. At 10, 30 and 90 days after the operation, the patient was reassessed for possible recurrences or alterations, but there were no complications or recurrence after the procedure. Discussion: Neoplasms of the male reproductive system are common in dogs. Sertolioma is considered one of the most frequent neoplasms in elderly dogs and that results in systemic clinical signs. This is in line with the 18-year-old dog described in the present report. In addition, it may result in clinical signs resulting from hyperestrogenism resulting from the neoplasm that is called paraneoplastic feminization syndrome. The characteristics of this syndrome are: gynecomastia, galactorrhea, pendular foreskin, atrophy of the penis and contralateral testicle, associated with dermatopathies, such as symmetrical bilateral alopecia. All these clinical signs were present. The diagnosis is made through complete anamnesis, complete clinical examination and complementary examination such as ultrasound help in the presumptive diagnosis, but only with histopathology can it be confirmed. In the clinical approach, histopathology was performed to close the diagnosis. Treatment is behind orchiectomy and total ablation of the scrotum, which was performed in the reported case. The treatment of choice was easy to apply, in addition to improving the patient's quality of life, promoting rapid post-surgical healing and an early return to normal life. However, for the effectiveness of the technique, the early diagnosis and collaboration of tutors is fundamental.

Cholangiocarcinoma in a bitch - multimodal diagnosis

Background: Hepatic tumors of primary origin account for 0.6% to 2.9% of cases in canine species, less common than hepatic metastases. The hepatic tumors are divided into hepatocellular tumors, neuroendocrine tumors, bile duct tumors or cholangiocarcinomas, and mesenchymal tumors. Cholangiocarcinomas, are classified according to their origin, being intrahepatic, extrahepatic, or gallbladder type. Cholangiocarcinomas are considered rare in dogs and cats with a ratio of 29% to 71% compared to hepatocellular carcinomas, accounting for 9% of the hepatic tumors. The present study aims to describe a case of cholangiocarcinoma in a bitch, focusing on the diagnostic approach. Case: A 10-year-old castrated bitch Poodle was attended presenting hypoglycemia and seizure crisis. The patient had previous exams of hemogram and serum biochemical profile, showing a discrete increase of the hepatic enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST), besides hypoglycemia. Previous ultrasound exam revealed the presence of a hepatic mass located between the right and square lobes, immeasurable, and significant splenomegaly. Abdominal palpation revealed the presence of immeasurable abdominal formation of undetermined origin. Abdominal computerized tomography (CT), glycemic curve, and insulin dosage were requested. Tomography exam showed an increase in hepatic volume with the presence of a heterogeneous formation in the right lateral lobe topography; increase in spleen dimensions and the presence of multiple nodules; and the presence of a nodule in the right lung, at the caudal thoracic region. The glycemic curve showed acute variations, and insulin dosage was between normal values. The animal was referred for surgery, as in abdominocentesis, it was observed the presence of hemorrhagic fluid, confirming active bleeding by ultrasonography. The owners chose for euthanasia. In the post-mortem evaluation the main lesion was confirmed of hepatic origin, with a massive, irregular, cavitary presentation, involving multiple hepatic lobes, and a single nodule was observed in the right caudal lobe of the right lung. Histopathological evaluation was considered inconclusive. Immunohistochemistry was performed and the association of the immunohistochemical profile with the morphological characteristics indicated diagnosis of cholangiocarcinoma. Discussion: The related symptomatology, in hepatic neoplasms, is generally considered non-specific, with reports of lethargy, vomiting, dyspnea, anorexia and weight loss, however, the dog in this study presented a unique manifestation of hypoglycemia and one episode of convulsive crisis resulting from it. The clinical manifestation observed was extremely unspecific making initial diagnosis difficult. The ultrasonographic examination was effective in evidencing the abdominal mass. In addition, abdominal CT was also performed, which confirmed the hepatic origin, detailing the macroscopic aspect. Biochemical analyses of ALT and AST showed a discrete increase. Biochemical changes may occur in dogs with hepatic neoplasms, although they are not specific. Functional pancreatic beta-cell tumors producing insulin are the most common cause of paraneoplastic hypoglycemia, although in the case the insulin dosage was within normal limits. In cases of nonislet cell tumor the mechanism is frequently associated with the production of insulin-like growth factor (IGF). In most cases the definitive diagnosis of cholangiocarcinoma can be obtained by histopathological examination, although in the present report the result obtained was inconclusive, requiring an immunohistochemical examination. Due to the aggressive and metastatic character of this neoplastic type, early detection becomes extremely important in order to maximize therapeutic chances, however, diagnosis may be difficult.

Recurrent thyroid carcinoma in a dog - diagnosis by 18F-fluorodeoxyglucose positron emission tomography

Background: Thyroid tumor is a common endocrine tumor that accounts for up to 3.8% of all tumors in dogs. Most of them are malignant and usually nonfunctional in dogs. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is an imaging modality that detects intracellular accumulation of radioactive deoxyglucose administered in the body and is used in combination with computed tomography to provide functional information with exact anatomical localization. It is used in human medicine to detect residual or recurrent head and neck neoplasm after treatments, such as surgical resection. This report describes the first case of diagnosing recurrent thyroid carcinoma (TC) through FDG-PET in a dog. Case: A 9-year-old castrated male Maltese dog presented with a palpable mobile mass in the right ventral cervical region. Radiography and ultrasonography (US) showed a radiopaque mass adjacent to the trachea, and the right thyroid gland was enlarged on computed tomography. The surgically excised mass was encapsulated and measured to be 2.3 × 1.0 × 3.4 cm (width x length x height) in size. Histopathologically, the mass was diagnosed as differentiated follicular TC, and gross and vascular invasions were observed. To prevent recurrence, postoperative carboplatin chemotherapy was performed for 5 months. Two months after completion of chemotherapy, a nodule of approximately 7 mm in diameter was detected in the thyroidectomy bed by US. FDG-PET scanning was performed as an effective means of evaluating the malignancy, local recurrence, and metastasis of differentiated follicular TC. The nodule had the dimensions of 2.8 × 5.9 × 8.6 mm, a maximum standardized uptake value (SUV) of 8.49, and a mean SUV of 5.6. The results of FDG-PET suggested the recurrence of TC; therefore, the second chemotherapy protocol using toceranib was applied for 16 months. After initiation of the 2nd chemotherapy, follow-up examinations were conducted approximately every 4 months. On the 134th day, although the nodule was not palpated, its size was observed to have increased to 5.0 × 3.8 × 13.6 mm on cervical US on the 232nd day, showing heterogeneous and hypoechoic parenchyma. On the 405th day, the tumor was enlarged to a size of 13.4 × 12.9 × 22 mm and identified as a lobular, amorphous shape, and its heterogeneity was increased. Moreover, 2 pulmonary nodules with well-defined margins were found on radiography in the left caudal lung lobe (9 × 10 mm and 12 × 12 mm [width × length]); thus, lung metastasis was suspected. On the 536th day, anorexia and lethargy occurred, and the dog was lost to follow-up. Discussion: In the present case, local recurrence of TC was suspected based on cervical US. Although US was useful as a screening tool, additional examinations were necessary for evaluating local invasiveness, malignancy, and nodal/distant metastasis. FDG-PET can detect recurrence at an early stage because it can sense increased tumor metabolism through physiologic absorption of FDG, even before the beginning of anatomic change in the lesion. Therefore, FDG-PET can assist in treatment planning and provide better prognosis. In humans, focal FDG uptake and a high maximum SUV in the thyroid gland on FDG-PET were associated with a higher risk of cancer. Because there was no evidence of neoplasia except the thyroid lesion during the FDG-PET examination, the tumor showed an increasingly malignant pattern of the thyroid gland on US during the follow-up period, and the metastatic pulmonary nodules were identified on the 650th day after the thyroidectomy, the present case was diagnosed as recurrent TC. This report describes the use of FDG-PET for diagnosing local recurrence of TC, pointing to FDG-PET as a potential strategy to evaluate loco-regional recurrence and distant metastasis of TC.

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

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

Non jaagsiekte retrovirus associated adenosquamous lung carcinoma in a goat

An 11-year-old pet goat presented a clinical history of acute respiratory distress with ultrasound diagnosis of wide lung injury. The animal was euthanized due to welfare reasons. At necropsy, it was found pleural effusion and adhesion on the right cranioventral thoracic region. The right cranial and middle lung lobes were firm and light gray with a neocavity containing purulent exudate. From the middle lobe, there was a nodular proliferation occupying alveolar spaces, densely cellular and composed by cuboid-columnar epithelial cells arranged in papillae and acini (60%), as well as polygonal cells arranged in nests with squamous differentiation (40%). Marked pleomorphism, anisocytosis and anisocariosis were also noted. A total of 39 mitosis figures for ten fields at 400x magnification were counted. Lung samples were negative for jaagsiekte retrovirus (JSRV) by PCR. Immunostaining for TTF1 and P53 occurred in zones of adenomatous and squamous differentiation, respectively. In MIB-1, 14% (82/594) of immunolabeled cells were observed in the squamous component. In conclusion, the histopathological and immunohistochemical characteristics confirmed the diagnosis of a pulmonary adenosquamous carcinoma, without JSRV involvement, in goat species.(AU)

Synergistic effect of oxytetracycline as a combination treatment with Carboplatin on MCF-7 breast cancer cell line / Efeito sinérgico da oxitetraciclina em um tratamento combinado com Carboplatina na linhagem de células cancerígenas pulmonares MCF-7

In breast cancer treatment, chemotherapy resistance is a major problem where many receptive tumors rebound and develop resistance. When provided in combination, cancer drugs are most successful, thus reducing the risk of developing resistant cancer cells. However, the evaluation of combination therapies has increased rapidly in recent years. Consequently, by repurposing old treatments, the discovery of additional medicines that may interact synergistically with chemotherapy is considered a current medical aim through discovering a new cancer medication or therapeutic strategy. The purpose of this research is to increase the anti-cancer activity of carboplatin (CP) by increasing the apoptotic effect of breast cancer cells (MCF-7) during in vitro experiments in combination with oxytetracycline. Our results showed a high synergistic effect between oxytetracycline and carboplatin, MCF-7 representative cell treated with carboplatin with/without different concentrations of oxytetracycline (5% and 10% of IC50). Oxytetracycline, which potentiated the action of carboplatin and/or had notable activity was reported as a single agent. This research demonstrated the synergistic relationship between oxytetracycline and carboplatin in viability assays. Surprisingly, our findings suggest that inhibiting treatment strategies can extend carboplatin's therapeutic window, potentially allowing for cancer therapy.(AU)

No tratamento do câncer de pulmão a resistência à quimioterapia é o maior problema no qual muitos tumores receptivos apresentam um rebote e desenvolvem a resistência. Quando oferecidas em combinações, as drogas anticancerígenas apresentam maior taxa de sucesso, reduzindo assim o risco de desenvolvimento de células cancerígenas resistentes. Contudo, a avaliação das terapias de combinação tem crescido muito rapidamente. Consequentemente, por reaproveitamento de tratamentos antigos, a descoberta de novos medicamentos adicionais que podem interagir sinergicamente com a quimioterapia que é considerada como auxílio médico na corrente busca à descoberta de novas medicações anticancerígenas ou estratégias terapêuticas. O propósito da presente pesquisa é aumentar a atividade anticancerígena da Carboplatina (CP) pelo incremento do efeito apoptótico de células de câncer pulmonar (MCF-7) em experimentos in vitro pela combinação com oxitetraciclina. Os resultados obtidos confirmaram elevado efeito sinérgico entre oxitetraciclina e Carboplatina em células MCF-7 representativas tratadas com Carboplatina, com e sem diferentes concentrações de oxitetraciclina (5% e 10% de IC50). A oxitetracilina que potencializou a ação da Carboplatina e/ou teve uma notável atividade relatada como um agente isolado. A pesquisa demonstrou a relação sinérgica entre oxitetraxiclina e Carboplatina nos ensaios de viabilidade. Surpreendentemente, os resultados obtidos sugeriram que as estratégias de tratamento inibidor podem aplicar um janela terapêutica da Carboplatina com potencial para a terapia do câncer.(AU)

The effect of size and clinical staging of mammary tumors on blood parameters in bitches

Background: Mammary tumors are the most common type of tumor in female dogs and account for 50% of all tumors in dogs. The clinical prognosis of canine mammary tumors is strongly affected by the size, stages, histological type, and grade of tumor; mitotic index; and nearby and distant metastasis. In canine mammary tumors, it is recommended that prognostic evaluation should also include complete blood count, serum biochemistry, and blood gases in addition to tumor size and stage. This study aimed to investigate the effect of tumor size, volume, and clinical stage on complete blood count, blood gas analysis, and serum biochemical parameters in bitches with mammary tumors and the correlation between them. Materials, Methods & Results: The study included a total of 18 bitches of different breeds, aged 6-15 years, of which 12 had mammary tumors and 6 were healthy. Thoracic X-rays were performed on bitches with mammary tumors in ventrodorsal and laterolateral positions to evaluate lung metastasis. Blood samples were collected from the cephalic vein from bitches in both groups in 2 different tubes (with plastic gel and ethylenediaminetetraacetic acid), 5 mL each, to perform complete blood count and evaluate blood gases and serum biochemical parameters. Blood samples were collected from the animals at the time of initial examination without any intervention. Analysis of the blood showed that bitches with mammary tumors had decreased levels of RBC, HCT, HGB, potassium, TCO2 , base excess, THbc, and ALT enzyme activity and increased levels of lactate, total protein, cholesterol, triglyceride, LDL, uric acid, and ALP and LDH enzyme activities compared with those in the control group. Furthermore, the dogs with a primary tumor of > 5 cm were found to have significantly higher levels of WBC, lactate, total protein, triglyceride, LDL, uric acid, and ALP and LDH enzyme activities and significantly lower levels of RBC and THbc compared with those in the control group. Bitches with tumors in multiple mammary lobes were found to have significantly higher levels of WBC, total protein, triglyceride, LDL, and ALP and LDH enzyme activities and significantly lower levels of RBC, HCT, HGB, TCO2 , THbc, and ALT enzyme activity compared with those in the control group. Based on the laboratory findings and approval of the owners of the dogs, mammary tissues containing the tumor and lymph nodes were surgically removed. After the operation, the removed mammary tissues were evaluated for size and volume. Clinical staging of the tumors was performed based on the size of the primary tumor (T), nearby lymph nodes (N), and metastasis (M) in accordance with the criteria set by WHO. Clinical staging of the tumors was, thus, based on the tumor, nodes, and metastases (TNM) score obtained according to the following system: Stage I: T1 N0 M0 , Stage II: T2 N0 M0 , Stage III: T3 N0 M0 , Stage IV: TanyN1 M0 , Stage V: made as TanyNanyM1 . Discussion: Mammary tumors are the most common type of neoplasm in bitches and, thus, cause serious problems in veterinary medicine. Tumors are significantly correlated with better prognosis compared with larger tumors. Based on this finding, this study investigated the effect of size, volume, and stage of mammary tumors in bitches on some blood parameters and the correlation between them. Therefore, it was concluded that clinical staging and evaluation of blood parameters could be useful in the diagnosis, treatment, and prediction of prognosis in canine mammary tumors. This study found that bitches with mammary tumors exhibited significant changes in their blood parameters (complete blood count, blood gas analysis, and serum biochemistry). The results obtained from this study may contribute to the development of approaches to the diagnosis, prediction of prognosis, and treatment of canine mammary tumors.

Metastatic vulvar squamous cell carcinoma in a mare

Background: Squamous cell carcinoma (SCC) is a common cutaneous neoplasm in horses, which mainly affects the external genitalia, oral cavity, and periocular region. The development of SCC metastases is rare in these animals, and the most common occurrence is a marked local infiltration. Exposure to ultraviolet rays and skin depigmentation are the main etiological factors of SCC. Definitive diagnosis of the neoplasm is performed through histological examination of lesions. The present report describes the clinical, anatomopathological, and immunohistochemical (IHC) aspects of a case of metastatic SCC, with the vulva as the primary site in a mare. Case: A 17-year-old mare, mixed breed, was referred to the Veterinary Hospital of the Universidade de Passo Fundo (UPF), with history of areas of depigmented skin (pinto coat), and clinical history of anorexia, frequent episodes of colic, and recumbency. During clinical evaluation, heart rate (68 bpm), rectal temperature (38.4ºC), and respiratory rate (48 mpm) were elevated, and the oral mucosa was pale. The mare also had an ulcerated tumor mass involving the vulva, which extended to the inguinal region and involved the mammary gland. A cytological aspirate of the vulvar tumor was performed, in which no neoplastic cells were found. Next, a biopsy of 2 distinct areas of the vulva was performed. The material was sent for anatomopathological examination, which showed markedly pleomorphic malignant squamous cells, with individual keratinization and high mitotic index, organized in trabeculae with rare keratin pearl-like formations. The exam allowed the diagnosis of SCC Grade II. Due to the poor prognosis and high cost of treatment, the owner consented to euthanasia and necropsy examination. During necropsy, the vulvar tumor mass was grayish, firm to hard, infiltrative, and had friable areas. Tumor foci suggestive of metastasis were also observed in inguinal, mesenteric, mediastinal and renal lymph nodes, adrenal glands, lung, pericardium, medullary canal, intercostal muscles, right 15th rib, and tissue surrounding the azygos vein. Samples from all organs were collected for anatomopathological examination. Diagnosis of metastatic vulvar SCC was confirmed through histological and IHC studies, which evaluated the expression of cytokeratins (AE1/ AE3), as well as the proliferative activity of neoplastic cells through the PCNA marker. Discussion: The diagnosis of metastatic SCC was obtained through the observed clinical, necroscopic, histological, and IHC characteristics. This neoplasm usually appears in depigmented regions exposed to ultraviolet light, and older animals are more likely to be affected. The mare in the present case had areas of depigmented skin (pinto coat). The animal was kept in a paddock outdoor and exposed to constant solar radiation. Although rare in horses, manifestation of anorexia, progressive weight loss, and frequent colic episodes and recumbency may be closely related to the multiple sites of metastasis in the present case. The main histological findings of the neoplasm were the dense proliferation of malignant squamous cells with individual keratinization, arranged in a trabecular pattern and with rare formations of keratin pearls, in line with previous studies. During IHC evaluation, the neoplastic cells showed expression of cytokeratins (AE1/AE3), as well as high proliferative activity evidenced by the PCNA marker. Given this background, the present report describes the clinical, anatomopathological, and IHC aspects of a case of metastatic SCC with a primary site in the vulva of a mare.

Abordagem diagnóstica de mastocitoma cutâneo metastático em canino / Diagnostic approach of metastatic cutaneous mastocytoma in dog

O mastocitoma é uma das neoplasias cutâneas mais comuns que acometem cães. O diagnóstico da doença é baseado em aspectos clínicos e laboratoriais, sendo a citologia e a histopatologia os métodos de eleição. Diante disso, o objetivo deste estudo é relatar a importância da ampla abordagem diagnóstica de mastocitoma cutâneo metastático em uma fêmea canina castrada, atendida no Hospital Veterinário da Universidade Estadual do Ceará, com uma neoformação em membro compatível com mastocitoma. O estadiamento da paciente foi feito através de exames laboratoriais de hemograma completo, e citologia aspirativa de linfonodo regional e medula óssea, que evidenciaram a presença de focos de metástase; bem como do exame de ultrassom abdominal, que evidenciou alterações no parênquima hepático e linfoadenomegalia ilíaco medial direita. Diante das suspeitas, optou-se pela eutanásia da paciente, cujo corpo foi enviado para os exames de necropsia e histopatologia, os quais confirmaram o diagnóstico de mastocitoma cutâneo de alto grau, com metástase em fígado, pulmão, medula e linfonodos. Desta forma pode-se concluir que o mastocitoma cutâneo metastático é uma neoplasia de diagnóstico multifatorial, em que a realização de exames hematológicos associados às análises citológicas, histopatológicas e de imagem são indispensáveis para estabelecer o diagnóstico definitivo para que seja determinada uma melhor conduta terapêutica e prognóstico de pacientes caninos.

Mast cell tumors are one of the most common skin neoplasms that affect dogs. The diagnosis is based on clinical and laboratory aspects, with cytology and histopathology being the preferred methods. Therefore, this study aims to report the importance of the broad diagnostic approach of metastatic cutaneous mastocytoma in a castrated a female dog attended at the Veterinary Hospital of the State University of Ceará, with a neoformation in a member compatible with mast cell tumor. The patient's staging was performed through laboratory tests of complete blood count, aspiration cytology of regional lymph nodes and bone marrow, which showed the presence of focus of metastasis, as well as the abdominal ultrasound examination, which showed changes in the liver parenchymas and right medial iliac lymphadenopathy. Given the suspicions, the patient was euthanized and the body was sent for necropsy and histopathological examination, which confirmed the diagnosis of high-grade cutaneous mast cell tumor, with metastasis in the liver, lung, bone marrow, and lymph nodes. Thus, it can be is concluded that mast cell tumor is a neoplasm of multifactorial diagnosis, where hematological tests associated with cytology, histopathological, and imaging analyses are essential to establish the definitive diagnosis to determine a better therapeutic behavior and prognosis of canine patients.

Esophageal squamous cell carcinoma in cats

Background: Esophageal neoplasms are rarely reported in cats. The frequency rate is less than 0.5% and those neoplasms are usually malignant. Esophageal squamous cell carcinoma (SCC) is an idiopathic epithelial neoplasm, invasive and metastatic that can induce partial or complete obstruction of the esophageal lumen. There is no breed or sex predisposition, and it is more common in cats over 8-years-old. Esophageal SCC is more frequent in the middle third of the esophagus. The prognosis is poor, as the cats are usually diagnosed at an advanced stage. This report aims to describe clinical, endoscopic, radiographic, and pathological features of two cases of esophageal squamous cell carcinoma in cats. Cases: A 11-year-old neutered male cat presenting regurgitation, weight loss, anorexia and dyspnea was referred to veterinary internal medicine care. Simple and contrast-enhanced radiographic images of the cervical and thoracic regions showed an alveolar pattern in the cranial lung lobes and signs of esophageal lumen irregularity and dilatation in the mediastinum topography. The upper digestive endoscopy showed a dilated esophageal lumen, and an irregular mass was observed in the thoracic esophagus involving the entire esophageal circumference. Biopsy fragments were collected, and the histopathological result was compatible with squamous cell carcinoma. The second case was a 10-year-old neutered male cat presenting hyporexia, regurgitation, dyspnea, tachypnea, and abnormal breath sounds. The ultrasound of the chest showed 3 amorphous hypoechogenic and heterogeneous areas in the right and left hemithorax between parietal and visceral pleura. The cytological examination was compatible with a malignant epithelial tumor. The patient died 3 months after the onset of clinical signs. At gross exam, it was observed a friable, irregular, and ulcerated mass of 5.0 x 3.0 cm in the middle third of the esophagus...

Melanomas em cães no Sertão do Nordeste do Brasil - epidemiologia, fatores de risco e achados clinicopatológicos / Melanoma in dogs in the backlands of Northeastern Brazil - epidemiology, risk factors and clinicopathological findings

Background: Melanoma is a malignant neoplasm that arises from melanocytes and malanoblasts. It is also more frequently reported in dogs than in other species. They may arise from melanocytes in the skin, on the surfaces of the mucous membranes, and eyes. The aim of this study was to describe the epidemiological aspects, risk factors and clinicopathological findings of melanoma in dogs in the backlands, northeastern Brazil. Materials, Methods & Results: A retrospective study was carried out in all biopsy samples and necropsy examinations of dogs, from January 2003 to December 2021, at the Animal Pathology Laboratory of the Federal University of Campina Grande, Patos, Paraiba, northeastern Brazil. Epidemiological data, clinical signs, and gross lesions were reviewed from the diagnostic laboratory reports. Samples of the skin, lymph nodes, central nervous system and organs of the thoracic and abdominal cavities were fixed in 10% buffered formalin, processed routinely for histopathology, embedded in paraffin wax, cut into 4 µm sections, and stained with hematoxylin and eosin (HE). Histological sections were also submitted to immunohistochemistry with the primary antibody anti-Melan A. Of the 4717 records found, 1158 (24.5%) were diagnosed with neoplasms, of which 48 (4.14%) cases were of melanoma. Of this total, 28 (58.3%) dogs were elderly, 19 (39.6%) were adults, and 1 (2.1%) was young. Mixed breed animals were the most affected (42.6%), followed by the pinscher breed (19.1%). According to the anatomical region, the most affected site was the skin (38/53=71.7%), followed by the oral cavity (12/53=22.65%) and the eyes (3/53=5.7%). Grossly, the skin lesions were characterized by exophytic and usually blackened, sometimes irregular and firm, nodules. At cut, they had a smooth, compact and blackened surface. Lesions in the oral cavity were characterized by blackened, irregular and infiltrating nodules or masses. The ocular lesions were always unilateral and were characterized by an enlarged and diffusely blackened eyeball, with areas of ulceration and subversion of tissue architecture. In 5 animals there was more than one anatomical site affected, totaling 53 lesions. In 9 (17%) cases, metastases were identified, 8 in regional lymph nodes and 1 in the lung. Histopathology showed a densely non-encapsulated, poorly delimited, expansive and infiltrative neoplasm, composed of neoplastic cells arranged in islands or nests and supported by fibrovascular stroma, containing a variable amount of brownish pigment (melanin). Immunohistochemistry showed strong immunostaining of the neoplastic cells in brown by the anti-Melan A antibody. Discussion: The diagnosis of melanoma was established based on epidemiological, clinical, anatomopathological, and immunohistochemical findings. Gender is not a predisposing factor, and although there was no statistically significant relationship, males were more affected. Senescence is a conditioning risk factor. Elderly animals were more affected (P < 0.0001) than adult ones, with OR = 4.38; and young ones (P = 0.0051), with OR = 12.65. Some breeds, especially those with marked skin pigmentation, were more affected, however the most affected ones in this survey were pinscher and poodle. Cutaneous melanoma accounted for almost 72% of cases, contesting recent studies where oral cavity melanoma was more frequent. Therefore, it is believed that the climatic conditions of the backlands sub-region, in northeastern Brazil, associated with the individual characteristics of the dogs, are involved in the development of these neoplasms, since the climate is predominantly dry, with high temperatures throughout the year, with maximums that can reach 40ºC, favoring the exposure to high incidence of ultraviolet radiation.

Linfoma mediastinal em gato com vírus da leucemia felina / Mediastinal lymphoma in a cat with feline leukemia virus

Background: Mediastinal lymphoma occurs at a high incidence in cats positive for feline leukemia virus (FeLV). It is a malignant lymphocytic neoplasm that may trigger clinical signs such as dyspnea, apathy, regurgitation, and weight loss. The objective of this work is to report a case of mediastinal lymphoma associated with FeLV in a cat, and describe the clinical, pathological, diagnostic, and therapeutic aspects that can help the diagnosis and treatment of this disease. Case: A 3-year-old male neutered cat weighing 4.6 kg, positive for FeLV, and with a history of dyspnea and hyporexia was referred to a private veterinary clinic in the city of Caxias do Sul, RS, Brazil. The only alteration found at the clinical examination was a muffled sound during lung auscultation. Radiographs of the thorax revealed the presence of pleural effusion; after drainage of the fluid, a mass located in the mediastinal area became radiographically observable. An analysis of the effusion fluid showed high cellularity characterized by a markedly pleomorphic population of individual round cells consistent with lymphocytes. Small lymphocytes with a high nucleus:cytoplasm ratio, round nucleus, condensed chromatin, and inconspicuous nucleoli were observed, along with medium and large lymphocytes. The medium and large lymphocytes were characterized by a variably increased nucleus:cytoplasm ratio and a scant to moderate cytoplasm exhibiting moderate to intense basophilia and, occasionally, vacuoles. The nuclei were round, idented, or irregular; most of them were located eccentrically and contained coarse to finely granular chromatin. Nucleoli varied from single to multiple, round to angular, and central to peripheral and prominent. Macronucleoli and marked anisonucleosis were also observed, as well as binucleated cells and rare multinucleated cells. The conclusion was that it was a case of neoplastic effusion caused by a lymphoma. After an appointment with an oncologist, a chemotherapy protocol was established. The treatment of choice was CHOP, a combination of cyclophosphamide (20 mg/kg orally), doxorubicin (1 mg/kg intravenously), vincristine (0.5 mg/m2 intravenously), and prednisolone with a regressive dose starting at 2 mg/kg. The patient underwent 4 rounds of chemotherapy, and received a maintenance treatment thereafter. The patient's condition remained stable for 390 days without relevant clinical or hematological alterations. Discussion: The diagnosis of mediastinal lymphoma was established by associating clinical finings, laboratory exams, and radiographic findings. Exams of utmost importance to reach this diagnosis were the thoracic radiography, which revealed the presence of a mass in the thorax, and the cytopathological analysis of the effusion fluid, as round cell neoplasms are easily dissociated. Young cats are the group most affected by FeLV, and mediastinal lymphoma is considered the most prevalent type of lymphoma in this species. The most common clinical sign is dyspnea; however, other signs such as apathy, weight loss, regurgitation (due to pressure on the esophagus), and Horner's syndrome (owing to pressure on the thoracic sympathetic innervation) may also occur. This disease is treated with chemotherapy, with CHOP frequently used as the chemotherapeutic protocol. The good therapeutic response for a longer time than the average estimated by studies on the prognostic of this disease indicates that a correct diagnosis along with an assertive approach and the cooperation of the tutor are essential in cases of mediastinal lymphoma.