Ovarian papillary carcinoma in a Mongolian gerbil (Meriones unguiculatus)

Neoplasms are among the most impacting disease diagnoses in veterinary medicine and have become increasingly common due to the greater longevity of animals as living conditions improved. The Mongolian gerbil is a small rodent species that has become popular recently. In these animals, the occurrence of neoplastic processes is relatively common, mainly tumors of the ventral gland in males and ovarian tumors in females. This work aims to report an ovarian tumor in a Mongolian gerbil Meriones unguiculatus Milne-Edwards 1867 (Rodentia, Muridae). At the initial presentation, the animal had dyspnea, prostration, and increased abdominal volume in the topography of the right ovary of approximately 2 cm. The animal was submitted to exploratory laparotomy because of the emergency nature of the case and the owners' refusal of additional exams due to financial restrictions. Thus, an ovariohysterectomy was performed, followed by a histopathological examination. The histopathology revealed an ovarian papillary carcinoma affecting both ovaries and cystic endometrial hyperplasia. With surgical removal and drainage of the thoracic fluid, the animal showed good recovery, with general improvement and return to regular activity, with a life expectancy of two years. Currently, the demand for specialized veterinarians for unconventional pets is increasing. This condition allows owners to raise their animals more properly, favoring greater longevity. Knowledge about the prevalence and incidence of diseases in different species is of enormous relevance in establishing the appropriate therapy, improving life quality, and increasing life expectancy in animals' lives.(AU)

Histone epigenetic modifications and their relationship with cancer: a comparative medicine view / Modificações epigenéticas de histonas e sua relação com o câncer: uma visão da medicina comparada

ABSTRACT: Epigenetic modifications have become highly important in the study of cancer pathogenesis due to research showing that changes in the expression of DNA-associated proteins can affect gene expression but may be reversible after treatment. The changing histones are being studied on a large scale in medicine while recent studies also show this relationship in veterinary medicine. Histone deacetylation is related to tumor progression and overexpression of histone deacetylases (HDACs) is responsible for these changes. The silencing of tumor suppressor genes related to epigenetic changes favors tumor progression; however, using HDAC inhibitors has been shown to effectively reverse these histone changes while having anticancer effects. This research provided an overview of comparative medicine between humans and dogs concerning epigenetic changes while showing the physiological mechanisms and the relationship between cancer and epigenetics, specifically regarding histone acetylation and deacetylation. This overview should contribute to a better understanding of epigenetics and cancer and their relationship with new target-molecular therapies in veterinary medicine and the importance of such studies.

RESUMO: Mudanças epigenéticas assumiram importância na patogênese do câncer a partir de pesquisas que mostraram que mudanças na expressão de proteínas associadas ao DNA podem afetar a expressão gênica e podem ser reversíveis após o tratamento. As alterações nas histonas têm sido estudadas em larga escala na medicina, particularmente no câncer de mama, e estudos recentes mostram essa relação também na medicina veterinária. A desacetilação das histonas está relacionada à progressão tumoral e a superexpressão de histonas desacetilases (HDACs) é responsável por essas alterações. O silenciamento de genes supressores de tumor relacionados a alterações epigenéticas favorece a progressão tumoral, entretanto, o uso de inibidores de HDAC é eficaz em reverter as alterações nas histonas e tem efeitos anticâncer. Uma visão da medicina comparada entre humanos e cães em relação às alterações epigenéticas, será o objetivo deste trabalho, mostrando os mecanismos fisiológicos e a relação entre o câncer e a epigenética, especificamente com a acetilação e desacetilação de histonas. Essa visão contribuirá para um melhor entendimento da epigenética e do câncer, bem como a relação com as novas terapias moleculares-alvo na medicina veterinária e a importância dos estudos neste contexto.

Clinical presentation, histological findings, and prognosis in female dogs with mixed mammary neoplasms / Apresentação clínica, achados histológicos e prognóstico em cadelas com neoplasias mamárias mistas

The aim of this study was to describe the clinical and morphological characteristics of mixed mammary neoplasms and verify what characteristics affect the prognosis of female dogs with carcinomas in mixed tumors and carcinosarcomas. This was a retrospective study of 67 female dogs that underwent mastectomies and were diagnosed with benign mixed tumors (n=13), carcinomas in mixed tumors (n=44) and carcinosarcomas (n=10). Data regarding the clinical and histological aspects of the neoplasms were collected and the relation with specific survival times, and hazard ratios (HR) in 24 months was calculated. In univariate analysis, the diagnosis of carcinosarcoma (HR 8.26, p=0.006), carcinomatous areas with micropapillary or solid patterns (HR 17.49; p=0. 001) and lymph node metastasis (HR 7.07;p=0.020) were associated with specific survival. In multivariable analysis, only micropapillary or solid pattern (HR=16.34; p=0.007) remained independent factor associated with lower specific survival. Micropapillary or solid carcinomatous patterns were associated with shorter specific survival time (p=0.002) among animals with carcinomas in mixed tumors. Among the carcinosarcomas, lymph node metastasis (p=0.010) was associated with a shorter specific survival time. In conclusion, carcinomas in mixed tumors and carcinosarcomas vary in prognosis depending on the carcinomatous proliferation patterns and spread of the disease.

O objetivo deste estudo foi descrever as características clínicas e morfológicas das neoplasias mamárias mistas e verificar quais características interferem no prognóstico de cadelas com carcinomas em tumores mistos e carcinossarcomas. Este foi um estudo retrospectivo de 67 cadelas, que foram submetidas a mastectomias e diagnosticadas com tumores mistos benignos (n = 13), carcinomas em tumores mistos (n = 44) e carcinossarcomas (n = 10). Foram coletados dados sobre os aspectos clínicos e histológicos das neoplasias e a relação com o tempo de sobrevida específica e a razão de risco (OR) em 24 meses foram calculadas. Na análise univariada, o diagnóstico de carcinossarcoma (HR 8,26; p=0,006), as áreas carcinomatosas com padrão micropapilar e sólido (HR 17,49; p= 0,001) e metástase linfonodal (HR 7,07; p=0,020) foram associadas à menor sobrevida específica. Na análise multivariável, apenas o padrão micropapilar ou sólido (HR=16,34; p=0,007) permaneceu como fator independente associado à sobrevida. Proliferações carcinomatosas micropapilares ou sólidas (p = 0,002) foram associadas a tempos de sobrevida específica mais curtos entre os animais com carcinomas em tumor misto. Entre os pacientes com carcinossarcoma, metástases em linfonodos (p = 0,010) foram associadas a um menor tempo de sobrevida específica. Em conclusão, os resultados mostraram que os carcinomas em tumores mistos e os carcinossarcomas podem ter prognóstico variável, dependendo do padrão de proliferação carcinomatosa e da disseminação linfática da doença.

Tumor neuroendócrino em coração de cão / Neuroendocrine tumor involving the heart of a dog

Background: Neuroendocrine tumors are epithelial tumors with predominant neuroendocrine differentiation. Ectopic thyroid carcinoma develops in the ectopic thyroid parenchyma, in the anterior mediastinum, being an important differential diagnosis of paraganglioma, although occurring less frequently than the same. The cells invade the mediastinal fat reaching the adventitia of the aorta. There is a possibility of metastatic formations in the lung, kidneys, and pancreas. A supporting treatment was provided. The present study proposes the exposition and description of a case of neuroendocrine tumor in the heart, considering the rarity of the involvement of this tumor in the canine species. Case: A 9-year-old American Bulldog male canine was treated at home in the city of Rio de Janeiro. On clinical examination, dyspnea, edema of the hind limbs and an increase in abdominal volume were observed. With the suspicion of congestive heart failure, mainly on the right, cardiac exams were requested. Because it was an aggressive animal, sedation was performed with a combination of tiletamine and zolazepam. During cardiac auscultation, the presence of S4 was noticed, characterizing a gallop rhythm. No alterations were observed on the electrocardiographic examination. The echocardiogram showed a tumor mass in the atrium and dilation of the venous return vessels. The tumor enveloped 80% of the atrium of a 9-year-old male American Bulldog. The abdominocentesis procedure was performed to drain abdominal free fluid. Furosemide, enalapril and digoxin were prescribed as a treatment. Three months after the start of treatment, the animal presented intense dyspnea that culminated in the death of the patient, who later had the body sent for necropsy and subsequent tissue collection for histopathological analysis. Based on the immunohistochemical markers chromogranin and synaptophysin, the work here presented describes a case of a neuroendocrine tumor suggestive of paraganglioma involving a dog's heart. Discussion: Brachycephalic dogs, such as Boxers, Bulldogs and Boston Terriers, are predisposed to the development of paragangliomas. The genetic predisposition is related to hyperplasia of the carotid bodies generated by chronic hypoxia, resulting from obstructive processes in the airways. As the reported dog is an American Bulldog, the possibility of the tumor in question was reinforced. Paragangliomas are more frequent in males from nine to thirteen years of age, commonly associated with other endocrine neoplasms. It is also an important marker present in paragangliomas. In contrast to the literature, the report points to a neuroendocrine tumor suggestive of paraganglioma, without eliminating the possibility of an ectopic thyroid tumor, because although TTF-1 appears in most thyroid tumors, not all of them are present, although it is very suggestive. Treatment in question, attributed to the control of right congestive heart failure, although with little effect, denotes that the obstructive process of the return pathway, even with the use of drugs that prevent congestion, did not delay the evolution of the disease. However, it is observed that the treatment resources for these tumors, whether by surgical or chemotherapy option, also have few answers. The lack of literature on ectopic thyroid tumors influences the diagnosis of paraganglioma. Thus, clinical and complementary findings, mainly along with immunohistochemistry, were essential in the diagnosis of neuroendocrine tumor. After 3 months of the start of the treatment, the animal died.

Extraskeletal osteosarcoma in the duodenum of a dog

Background: Osteosarcoma is the most observed primary bone tumor in dogs, and may affect the appendicular and axial skeletons. In addition, it may be present in extraskeletal form, accounting for only 1% of cases. As shown by few reports in the literature, the involvement of the intestinal region by is rare. The objective of this study was to report the case of a 13-year-old Yorkshire dog, submitted to an exploratory laparotomy for suspected partial intestinal obstruction, diagnosed with extraskeletal osteosarcoma. Case: A 13-year-old dog, Yorkshire Terrier, male, presented clinical signs of gastrointestinal abnormalities. An ultrasound examination was performed and was found a mass in small intestine region with wall and lumen invasion. Then, was realized exploratory laparotomy and detected intestinal obstruction due to a mass with approximately 5.0 x 6.0 x 4.4 cm localized in duodenum. Surgical removal was performed and the sample sent to the veterinary diagnostic laboratory for histopathological examination. The sample had an irregular surface and firm consistency. In addition, when cut, the mass enveloped the intestinal layers and sometimes obstructed the lumen. Then, the sample were processed routinely for histopathology. After that, in microscopy evaluation was detected cell proliferation, affecting all layers of intestine. In detail, cells were elongated with pleomorphism marked and atypical mitosis. In addition, there was production of cartilage and bone matrix. So, due the absence of others sites, the neoplasm was considered primary of intestine. After that, to evaluate the expression of KI-67 and COX-2 was performed, and the cell proliferation index was 54.0% and the COX-2 expression was moderate in less than 10% of neoplastic cells. After the surgery, the patient was hospitalized for a week and continue the treatment in home. Afterwards, the tutor received the diagnosis, but even though he was instructed on the severity of the case, he chose not to undergo chemotherapy. After three months, the patient presented abdominal fluid and nodules in your liver, suggesting metastasis, but without diagnosis confirmation. The patient died five months after the diagnosis of extraskeletal osteosarcoma. However, no necropsy was realized, impossibility the diagnosis confirm. Discussion: The frequency of extraskeletal osteosarcoma in dogs remains unknown, with the mammary glands being the most affected site. In the present study, osteosarcoma affects the duodenal region and no reports of this neoplasm in the duodenum of dogs have been found in the literature. The clinical sign of dyschezia was important for the tutor to refer the animal to the veterinarian and perform the ultrasound in an attempt to elucidate the case, as the tumor mass is not always palpable. Histopathological examination and immunohistochemistry were necessary for the differential diagnosis and to establish the prognosis, although after the surgery the tutor chose not to perform chemotherapy. Extraskeletal osteosarcoma are usually highly metastatic, mainly affecting the lymph nodes and liver. In this case, the patient presented a liver nodule three months after the tumor removal surgery, but unfortunately, there was no diagnostic confirmation. Such neoplastic type is rarer and more aggressive than appendicular and axial osteosarcoma, with an average survival of 1 to 3 months. In this case, as a necropsy was not obtained, we cannot attribute the survival time to the disease. The survival rates of osteosarcomas in dogs are few months, but in the present case, although the patient died five months after surgery, the failure to perform a necropsy compromises the attribution of survival time to extraskeletal osteosarcoma.

Cutaneous epitheliotropic lymphoma in a Lhasa Apso

Background: Lymphoma neoplasms originate from the lymphocytes. Anatomically, these tumors can be classified into multicentric, digestive, mediastinal, and cutaneous forms. The etiology of cutaneous lymphoma remains unclear; however, it has been associated with chronic skin inflammation. The definitive diagnosis is based on histological analysis and immunohistochemistry, although fine-needle aspiration cytology has shown good results. The aim of this paper is to describe the clinicopathological aspects of a case of cutaneous epitheliotropic T cell lymphoma, classified as mycosis fungoides, in a Lhasa Apso dog. Case: A 8-year-old bitch Lhasa Apso with multiple non-pruritic skin nodules and history of 10-day evolution was referred to the Veterinary Hospital of the Centro Universitário do Espírito Santo (UNESC), Colatina, ES, Brazil. The nodules were erythematous, exophytic, firm, circumscribed, and measured 0.2-4 cm in diameter in locations throughout the animal's body. An incisional biopsy was performed with an 8-mm punch and sent for histopathological examination. An infiltrative, poorly demarcated, non-encapsulated, densely cellular neoplasm, which was replacing the dermal collagen and displacing the adnexa, was observed in the dermis. The tumor was composed of a population of round cells, with generally distinct cell borders and a small-to-moderate amount of eosinophilic cytoplasm. The nuclei were irregularly rounded and occasionally edentulous, with vesicular chromatin, a visible nucleus, and 11 mitotic figures in an area of 2.37 mm2 . The immunohistochemical test, which was positive for the CD3 marker, confirmed the diagnosis of T cell lymphoma. On an ultrasound to identify metastasis, the liver showed heterogeneous parenchyma, heterogeneous expansive formation, areas of cavitary appearance, and cytology compatible with lymphoma. Antineoplastic chemotherapy was administered using the CHOP regimen (cyclophosphamide, doxorubicin, vincristine, and prednisone). However, the animal died after 45 days. Discussion: A diagnosis of the mycosis fungoides type of cutaneous epitheliotropic T cell lymphoma was established based on clinical, laboratory, anatomopathological, and immunohistochemical findings. Pruritus is a common clinical condition in animals with mycosis fungoides, particularly in those with the erythrodermic form of the disease. Epitheliotropic lymphomas have no sexual or racial predilections and usually affect dogs over 9 years of age. The Cocker Spaniel, English Bulldog, Boxer, Golden Retriever, Scottish Terrier, Briard, English Springer Spaniel, Beagle, German Shepherd, and English Cocker Spaniel breeds are frequently affected by these lymphomas. These neoplasms can have a primary skin origin, or they can be secondary and associated with lymphoma found elsewhere in the body. Chemotherapy is the treatment of choice, especially in cases with multifocal distribution. Protocol preference varies with disease stage, patient clinical and laboratory conditions, and the degree of toxicity. Commonly used chemotherapy regimens include L-CHOP (vincristine, cyclophosphamide, doxorubicin, L-asparaginase, and prednisolone), CHOP, COP (cyclophosphamide, vincristine, and prednisone), LAP (lomustine, L-asparaginase, and prednisolone), LOPP (lomustine, vincristine, procarbazine, prednisolone), chlorambucil, and prednisolone. The prognosis of canine epitheliotropic cutaneous lymphoma is unfavorable, with a survival time ranging from a few months to 2 years. The animal in this study survived for 105 days. In addition, epitheliotropic cutaneous T cell lymphoma is aggressive, which may result in a shorter survival time in animals affected by this type of tumor.

Cutaneous myxoma in broiler chicken detected during slaughtering

Background: A cutaneous or superficial myxoma is a benign neoplasm of dermal or subcutaneous fibroblast origin. Although rare, it has been previously described in several species, including poultry. It presents as a single node or soft mass with a gelatinous cut surface. Histopathological analysis is essential for diagnosis and to differentiate it from other mesenchymal neoplasms and inflammatory or degenerative processes. Microscopically, it consists of dermal or subcutaneous lobules of plump, stellate, or spindle-shaped, bland-looking cells embedded in a basophilic myxoid matrix. This report describes the pathological findings in a rare case of cutaneous myxoma in a 42-day-old broiler flock. Cases: During ante mortem inspection of a 42-day-old broiler flock at a slaughterhouse under the authority of the Federal Inspection Service (southern Brazil), nodular lesions or encrusted areas with yellow and black areas were observed in the head skin of less than 1% of animals. These lesions, approximately 0.5 cm in diameter, were observed on the comb, in the periocular skin region, and close to the animals' nostrils. During the breeding period, no health or epidemiological events were observed. Fragments of the lesions in the comb and periocular skin were collected and fixed in buffered 10% formalin. The samples were sent to the laboratory, routinely processed, and stained with hematoxylin and eosin and Alcian blue. Microscopically, the lesions consisted of irregular multifocal proliferation of connective tissue showing spindle cells with poorly demarcated borders and scarce cytoplasm in a slightly basophilic myxoid aspect matrix. The adjacent epidermis is compressed due to neoplastic proliferation. No areas of epithelial hyperplasia or inclusion bodies were observed. According to the pathologic description and considering its descriptive epidemiology, our main clinical suspicion was cutaneous fowl pox, a pathology characterized by the appearance of nodules in regions devoid of feathers. However, the microscopic changes observed were compatible with those described for cutaneous myxomas. In addition, the extracellular matrix was positive for Alcian Blue staining, which is an indicator of myxoma. In the present case, the SIF did not report the same macroscopic lesions in other flocks of the same origin. Discussion: Connective tissue tumors, including myxomas, occur considerably less frequently under field conditions. In addition, these neoplasms are more frequent in mature birds and are not usually described in broilers, as observed in this report. The cutaneous myxoma described in broilers is usually a sporadic neoplasm that does not cause zootechnical losses, as observed in the case report. Its etiology is unknown and has been associated with various factors, such as local trauma and foreign bodies. Some fragments of plant material from the breeding environment were microscopically detected in the encrusted areas, which may indicate previous trauma or a foreign body. Myxoma has been associated with avian leukosis virus (ALV) subgroup A, but SIF did not report the same macroscopic lesions in other flocks of the same breeder hen's origin in the present case. Furthermore, sporadic connective tissue tumors associated with the virus occur in mature chickens but not in broilers. Myxoma lesions should be considered in the differential diagnosis of other connective tissue tumors and infectious agents that cause lesions in the skin and subcutaneous tissue.

A comparative analysis of anatomopathological features and COX-2 expression of mammary neoplasms with malignant mesenchymal components in female dogs / Análise comparativa das características anatomopatológicas e expressão de COX2 em neoplasias mamárias com componentes mesenquimais malignos em cadelas

ABSTRACT: Canine mammary neoplasms with malignant mesenchymal components, such as carcinosarcomas and sarcomas, belong to an uncommon and histologically heterogeneous group. Little is known about the biological behavior of these histogenic variants. This study aimed to compare the clinicopathological characteristics and the COX-2 immunohistochemical expression of different histologic subtypes of carcinosarcomas and sarcomas. Samples of 23 carcinosarcomas and 15 sarcomas from the mammary glands of female dogs were studied. Medical records were reviewed to obtain clinical data. Subsequently, histology microscope slides were analyzed to assess for mesenchymal subtypes, necrosis, vascular invasion, histologic grades, and lymph node metastasis. Immunohistochemistry was used to assess the COX-2 expression. The malignant mesenchymal proliferation was categorized into osteosarcomas (23/40), fibrosarcomas (5/40), liposarcomas (6/40) and chondrosarcomas (4/40). The osteosarcomatous differentiation was the most predominant type among the sarcomas and carcinosarcomas and was associated with vascular invasion (P=0.010) and lymph node metastases (P=0.014). High COX-2 expression was detected in 14.3% of the carcinosarcomas (carcinoma and/or sarcoma cells) and 27.3% of the sarcomas. The carcinosarcomas and sarcomas had similar clinical and pathological characteristics and developed as large tumors, with intratumoral necrosis and a predominance of high histologic grades, although the frequency of vascular invasion and lymph node metastasis was low. Osteosarcoma subtypes presented more aggressive characteristics than non-osteosarcoma subtypes.

RESUMO: Neoplasias mamárias caninas com componentes mesenquimais malignos, como carcinossarcomas e sarcomas, são um grupo de neoplasias pouco frequentes e histologicamente heterogêneas e pouco se sabe sobre o comportamento biológico das variantes histogênicas. O objetivo desse estudo é comparar as características anatomopatológicas e a expressão imunoistoquímica de COX-2 de diferentes subtipos histológicos de carcinossarcomas e sarcomas. Foram estudados 23 carcinosarcomas e 17 sarcomas da glândula mamária de cadelas. Os prontuários médicos foram revisados para obtenção de dados clínicos. Posteriormente, as lâminas histológicas foram avaliadas para acessar os subtipos mesenquimais, necrose, invasão vascular, grau histológico, metástase linfonodal. A imunoistoquímica foi realizada para avaliar a expressão de COX-2. Os tipos encontrados de proliferação mesenquimal maligna foram osteossarcoma (23/40), fibrossarcoma (7/40), lipossarcoma (6/40) e condrossarcoma (4/40). A diferenciação osteossarcomatosa foi predominante entre os sarcomas e carcinossarcomas e foi associado com invasão vascular (P=0,006) e metástase linfonodal (P=0,014). Uma expressão alta de COX-2 foi detectada em 14,3% dos carcinossarcomas (células carcinomatosas e/ou sarcomatosas) e 27,3% dos sarcomas. Os carcinossarcomas e sarcomas apresentaram características clínicas e patológicas semelhantes e se desenvolveram como tumores grandes, com necrose intratumoral e predomínio de alto grau histológico, mas com baixa frequência de invasão vascular e metástase distante. Os subtipos osteossarcomatosos apresentaram características mais agressivas quando comparados com subtipos não osteossarcomatosos.

Canine mixed tumors as one of the mammary neoplasia varieties

The most significant interest in veterinary oncology is occupied by tumors of a mixed nature, which are represented by the direct interaction of epithelial and mesenchymal components. According to some data, the formation of cell lineage of mesenchymal cells occurs due to the transformation of epidermal basket cells surrounding the glandular epithelium. In this case, the formation of a cartilage anlage with its further transformation into differentiated bone tissue occurs. The article contains information about the structure and features of the location and interaction of mixed tumors' glandular and stromal components in female dogs (n=29). It was revealed that in addition to simple mixed neoplasms, tumors with proplasia of the mesenchymal component into highly differentiated cartilage or bone tissue were also often registered. To confirm subcellular changes in the expression of certain types of proteins, such as a-SMA and vimentin, an IHC study was used. The expression of the studied biomarkers was established in mesenchymal fibroblastic differon cells and myoepithelial cells. The intensity of immunoreactive material expression ranged from moderate (2+) to strong (3+), indicating changes in myoepithelial cells' genotype during the formation of mixed mammary neoplasms.(AU)

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.

Diagnosis of transmissible venereal tumors in bitches - platelet indices are a remarkable marker?

Background: Hematological analyses are seen as more preferred laboratory analyses in canine transmissible venereal tumor studies. There is no information about the availability of platelets and their indices in routine practice in canine transmissible venereal tumor cases. Taking this as a starting point, this study analyzed the usefulness of platelet indices in dogs with transmissible venereal tumor in clinical laboratory diagnosis as well as examined the relationship between white blood cells, red blood cells, platelets (PLT), main platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT), and the ratio of main platelet volume to platelets (MPV/PLT). Materials, Methods & Results: In the study, a total of 42 bitches of various breeds were used. Nineteen healthy bitches were used as a control group, and the others 23 with cTVT as a study group. Metastasis was not observed in any of the bitches involved in the study. History, clinical findings, and cytological examinations were evaluated for the diagnosis of cTVT. In animals with hemorrhagic discharge and neoplastic lesions, a vaginal cytological examination was performed. Typical TVT cells with large nuclei and intracytoplasmic vacuoles were observed in the vaginal cytological examinations, and the diagnosis of TVT was made. Healthy bitches (19) and those with TVT (23) were 39.16 5.37 months and 47.61 5.14 months old, respectively. From all animals, 2 mL blood samples were collected from V. cephalica to evaluate PIs in the complete blood count (CBC). Collected blood samples were analyzed using an automated hematology analyzer. As a result of the analysis, WBC, RBC, HGB, HCT, MCV, MCHC, RDW, PLT, MPV, PDW, PCT, and MPV/PLT data were obtained. Mild leukocytosis, an increase in PLT, and a decrease in MCV and MPV/PLT were determined in the study group compared to the control group. Cut-off values in CBC of bitches with TVT were determined as WBC: 13.35 (sensitivity: 78%; specificity: 90%); MCV: 67 (sensitivity: 57%; specificity: 95%); PLT: 315.50 (sensitivity: 65%; specificity: 74%); and MPV/PLT: 0.028 (sensitivity: 78%; specificity: 58%). In CBC analyses, a strong negative correlation between PLT and MPV/PLT was detected in both groups. Discussion: Canine transmissible venereal tumors are common in both stray and pet dogs. It is naturally transferred from animal to animal during mating by live tumor cells. This tumor can commonly affect the external genitalia and internal organs in some cases. It generally has the look of cauliflower, and its surface is ulcerated, inflammatory, hemorrhagic, and infectious. More preferred laboratory analyses are complete blood count and blood chemistry analysis in cTVT for to evaluate the success of treatments. Platelet indices have been investigated in many diseases such as endotoxemia, chronic enteropathy, mammary tumor, parvoviral enteritis, septic peritonitis, lymphoma, pyometra, visceral leishmaniasis, and babesiosis in dogs. There is no information available for either diagnostic or prognostic use of the PIs in canine TVT cases. Ultimately, in light of the presented study's results, platelet indices, especially PLT and the MPV/PLT ratio, seem to be notable laboratory markers in terms of easy accessibility and low-cost assessment techniques in canine transmissible venereal tumor cases. New data, however, should be established by a thorough follow-up study using a larger sample size and addressing its usefulness as a diagnostic or prognostic marker in canine transmissible venereal tumors.

Efficacy of fine needle aspiration in the diagnosis of spontaneous mammary tumors / Eficácia da citologia aspirativa no diagnóstico de tumores mamários espôntaneos / La eficacia de la aspiración con aguja fina en el diagnóstico de tumores mamarios espontáneos

The cytopathology exam has been utilized to diagnose mammary disorders in female dogs. The success of cytopathology results depends on, among other factors, the diagnostic accuracy of the exam. The present study aimed to compare the cytopathological and histopathological findings from mammary disorder cases in female dogs and evaluate the lesion cytopathology exam accuracy. The concordance degree was evaluated between the cytopathology and histopathology exams of 67 female dogs, carriers of palpable breast lumps, cared for at the university hospital from which the following indicators were calculated: sensitivity, specificity, positive predictive value, negative predictive value, false positives, false negatives, and exam accuracy. The sensitivity was 95.23%, the specificity 75%, positive predictive value 98.36%, negative predictive value 60%, and accuracy 94.02%. There were 2 false negatives and 1 false positive. In conclusion the cytopathology exam can be amply utilized as a means of diagnosis with high accuracy and sensitivity in the first examination of female dogs with mammary tumors.(AU)

O exame citológico tem sido utilizado no diagnóstico das afecções mamárias das cadelas. O êxito no resultado da citologia dependerá, além de outros fatores, da acurácia diagnóstica deste exame. O objetivo deste estudo foi comparar os achados citológicos e histológicos das afecções mamárias de cadelas e avaliar a acurácia do exame citológico nestas lesões. Avaliou-se o grau de concordância entre os exames citológico e histológico de 67 cadelas, portadoras de nódulo mamário palpável, atendidas em um hospital universitário e foram calculados os indicadores: sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo, falso positivo, falso negativo e acurácia do exame. A sensibilidade foi de 95,23%, a especificidade de 75%, o valor preditivo positivo de 98,36%, o valor preditivo negativo de 60% e a acurácia de 94,02%. Ocorreu 1 resultado falso positivo e 2 falso negativos. Conclui-se que o exame citológico pode ser amplamente utilizado como meio de diagnóstico com elevada acurácia e sensibilidade no atendimento primário das cadelas com tumor de mama.(AU)

El examen citológico se ha usado en el diagnóstico de cáncer de mama en perras. El éxito de la citología depende, entre otros factores, la precisión diagnóstica de este examen. El objetivo de este estudio fue comparar los resultados de citología y examen histológico de las enfermedades de mama en las perras y evaluar la exactitud de la citología de estas lesiones. Se evaluó el grado de acuerdo entre los exámenes citológicos e histológicos de 67 perros, que sufren de bulto palpable en la mama atendidos en un hospital universitario y se calcularon los indicadores: sensibilidad, especificidad, valor predictivo positivo, valor predictivo negativo, falsos positivos, falsos negativo y exactitud de la prueba. La sensibilidad fue del 95,23%, especificidad 75%, valor predictivo positivo del 98,36%, valor predictivo negativo del 60% y el 94,02% de precisión. Hubo un resultado positivo falso y dos falsos negativos. Se concluye que el examen citológico puede ser ampliamente utilizado como una herramienta de diagnóstico de alta precisión y sensibilidad en la atención primaria de perros con cáncer de mama. (AU)

Multilobular tumor of bone in bitches: clinical, histopathological, immunohistochemical and overall survival aspects

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

Epidemiological, clinical, and therapeutic aspects of canine transmissible venereal tumor in Rio de Janeiro, Brazil (2015-2020) / Aspectos epidemiológicos, clínicos e terapêuticos do tumor venéreo transmissível canino no Rio de Janeiro, Brasil (2015-2020)

Canine transmissible venereal tumors (TVT) have a high incidence in Brazil. This is partly due to the large population of stray dogs and the ineffectiveness of epidemiological control programs. This study aimed to describe the epidemiological data, clinical manifestations, and treatments used in dogs affected by TVT. Data were retrospectively collected from the 2015-2020 records of the Veterinary Hospital of the Federal Rural University of Rio de Janeiro. A total of 252 dogs were diagnosed with TVT during the study period. Of these, 81.3% were mixed-breed, 50.4% were males, and 88.9% were young or adult animals. The genital region only was affected in 77.3% of cases. Exclusively extragenital lesions were observed in 22.6% of cases. Among the animals seen, 40.1% received no treatment. Of those treated, 99.3% underwent a vincristine sulfate protocol, and in 77.2%, the treatment resulted in total remission of the neoplasm after 4 to 6 chemotherapy sessions. It was concluded that TVT is a neoplasm most often seen in mixed-breed dogs and located in the genital region, with hemorrhagic secretion being the main clinical sign reported by owners. Vincristine sulfate is currently the most used therapy, with high efficacy. However, despite the good prognosis, there was a high rate of non-adherence or abandonment of treatment, and this is an important factor to be considered and addressed by veterinarians.

O tumor venéreo transmissível (TVT) apresenta elevada incidência no Brasil, relacionada a elevada população de caninos errantes e a ineficácia dos programas de controle epidemiológicos. O objetivo do estudo foi descrever dados epidemiológicos, manifestação clínica e o tratamento empregado em cães acometidos pelo TVT no Hospital Veterinário da Universidade Federal Rural do Rio de Janeiro entre os anos de 2015 e 2020. Foram diagnosticados 252 cães com TVT durante o período do estudo, sendo 81,3% cães sem raça definida, 50,4% machos e 49,6% fêmeas, e com 88,9% animais jovens ou adultos. A região genital foi acometida em 77,3% dos casos. Lesões exclusivamente extragenitais foram observadas em 22,6% dos casos. Quanto ao tratamento, 40,1% dos cães não receberam tratamento. Entre os animais tratados, 99,3% utilizaram protocolo com sulfato de vincristina e em 77,2% o tratamento resultou em remissão total da neoplasia, com a realização de 4 a 6 sessões do quimioterápico. Conclui-se que o TVT é uma neoplasia frequentemente relacionada a cães sem raça definida, localizados na região genital, com secreção hemorrágica sendo o principal sinal clínico reportado pelos proprietários. O sulfato de vincristina é a terapia mais empregada, com alta eficácia. Entretanto, apesar de ser uma neoplasia com bom prognóstico, o alto índice de não adesão ou abandono ao tratamento representa um importante fator a ser considerado e trabalhado pelos médicos veterinários.

Lomustine for treatment of canine transmissible venereal tumor / Eficácia da lomustina no tratamento do tumor venéreo transmissível canino

Canine transmissible venereal tumor (TVTC) is a highly casuistic transmissible neoplasm in Brazil. Chemotherapy with vincristine sulfate is considered the treatment of choice, but the need for weekly applications and hematological monitoring, in addition to costs, are obstacles to owners' adhesion to the treatment. Lomustine is an alkylating class antineoplastic agent, and because it is administered orally, it is a more practical and less costly treatment option for the owners of animals with neoplasms sensitive to the drug. This study evaluated the therapeutic efficacy of lomustine in dogs affected by TVTC. Twelve dogs with cytopathological diagnosis of natural genital TVTC were selected. The dogs were submitted to the experimental protocol with lomustine administration at doses of 70 to 85 mg/m2 orally every 21 days, totaling a maximum of two administration cycles. The animals were reevaluated every 7 days until a maximum of +49 days after the first dose of lomustine, to monitor the regression of neoplastic lesions through measurements. Among the 12 dogs submitted to the lomustine protocol, 8/12 achieved complete remission of the neoplasm and were considered cured (66.6%), 1/12 had partial response to treatment (8.33%) and 3/12 had stable disease (25%). Important adverse effects such as severe neutrophilic leukopenia were detected in 3/12 dogs (25%). The clinical study indicated that lomustine may be a treatment option for TVTC.

O tumor venéreo transmissível canino (TVTC) é uma neoplasia transmissível de elevada casuística no Brasil. A quimioterapia com sulfato de vincristina é considerada o tratamento de escolha, mas a necessidade de aplicações semanais e acompanhamento hematológico, além dos custos, são obstáculos à adesão dos proprietários ao tratamento. A lomustina é um antineoplásico da classe dos agentes alquilantes e, por ser administrado por via oral, representa um opção de tratamento mais prática e menos onerosa para os proprietários de animais com neoplasias. O objetivo deste estudo foi avaliar a eficácia terapêutica da lomustina em cães acometidos por TVTC. Foram selecionados 12 cães com diagnóstico citopatológico de TVTC genital de ocorrência natural. Os cães foram submetidos ao protocolo experimental com administração de lomustina nas doses de 70 a 85 mg/m2 por via oral a cada 21 dias, totalizando no máximo dois ciclos de administração. Os animais foram reavaliados a cada sete dias até um máximo de +49 dias após a primeira dose de lomustina, para monitorar a regressão das lesões neoplásicas por meio de mensuração das lesões. Entre os 12 cães submetidos ao protocolo, 8/12 obtiveram remissão completa da neoplasia e foram considerados curados (66,6%), 1/12 tiveram resposta parcial ao tratamento (8,33%) e 3/12 tiveram doença estável (25%). Efeitos adversos importantes, como leucopenia neutrofílica grave, foram detectados em 3/12 cães (25%). O estudo clínico indicou que a lomustina pode ser uma opção de tratamento para TVTC.

Cytological grading of canine mast cell tumors: correlation with histologic grading and survival time / Graduação citológica de mastocitomas caninos: correlação com graduação histológica e sobrevida

ABSTRACT: Mast cell tumors are one of the most common neoplasia in dogs and cytopathology and/or histopathology examinations are used for diagnosis. Histologic grading is considered the gold standard test to predict the prognosis of this neoplasia. However, studies have been conducted using the cytological grading system to provide similar information in a faster, less invasive, and more accessible way. This study aimed to investigate cytological graduation and correlate it with histological grading and the survival time of dogs diagnosed with cutaneous mast cell tumors at the Veterinary Hospital of "Universidade Federal de Uberlândia" over five years. For that, cytological and histological slides from 72 animals were reviewed. The statistical methods used were the kappa test for agreement between grading systems, the Kaplan-Meier for survival time, Cox regression for comparison of cytological and histological grades and survival time. The cytological grading when compared to the two-tier histologic grading, high and low grades, had a moderate agreement (kappa 0.566). When the correlation between survival time and the cytological grade was evaluated, there was a higher death rate in the group with high-grade mast cell tumors compared to low grade, pointing to a correlation between survival time and cytological grade (p=0.009). In conclusion, the cytological grade is useful to treatment planning and providing prognostic information that precedes tumor removal, showing a good correlation with the two-tier histologic grading and with the survival time of the animals.

RESUMO: O mastocitoma é uma das neoplasias cutâneas mais comum nos cães e os exames citopatológicos e/ou histopatológicos são utilizados para diagnóstico. A graduação histológica é considerada padrão ouro para prever o prognóstico dessa neoplasia. Contudo, estudos têm sido realizados visando utilizar graduação citológica para fornecer informações semelhantes de maneira rápida, menos invasiva e mais acessível. Esse trabalho objetivou realizar graduação citológica e correlacionar com as graduações histológicas e com a sobrevida de cães diagnosticados com mastocitoma cutâneo no Hospital Veterinário da Universidade Federal de Uberlândia durante 5 anos. Para isso, lâminas de citologia e histologia de mastocitomas de 72 animais foram revisadas. Os métodos estatísticos utilizados foram teste kappa para concordância entre os sistemas de graduação, método Kaplan-Meier para tempo de sobrevida dos animais, e análise pela regressão de Cox para comparação do grau citológico e grau histológico e o tempo de sobrevida global. A graduação citológica quando comparada com a histológica de dois níveis, alto grau e baixo grau, obteve uma concordância moderada (kappa 0,566). Na avaliação da correlação entre sobrevida e grau citológico, houve maior taxa de óbito no grupo de cães com mastocitoma de alto grau, comparado aos de baixo grau, sendo observada correlação entre a sobrevida e o grau citológico (p=0,009). Esse estudo concluiu que o grau citológico é útil para o planejamento do tratamento e para fornecer informações prognósticas que antecedem a exérese do tumor, tendo boa correlação com a graduação histológica de dois níveis e com a sobrevida dos animais.

Scrotal hemangiosarcoma in a Large White boar / Hemangiossarcoma na bolsa escrotal de um reprodutor Large White

Tumors are rarely diagnosed in swine specie because of the short lifespan of production animals. Normally, these tumors do not present any clinical signs and are often detected at the time of slaughter. A 2-year-old Large White boar, used in the reproductive management of a farm and without a history of pre-existing problems, was examined for skin lesions on the scrotum. Samples were collected from skin segments containing lesions for histopathological and immunohistochemical diagnosis. Microscopically, the nodes in the scrotum pouch consisted of poorly demarcated, highly cellular, expansile, and multifocally invasive neoplasms, composed of immature endotheliocytes organized into neovascular formations. The tumor cells were pleomorphic, slightly oval to spindle-shaped, with eosinophilic cytoplasm and hyperchromatic nuclei with one to three nucleoli. All the nodules analyzed were compatible with hemangiosarcoma. After immunohistochemical evaluation, for the quantification of tissue angiogenesis the neoplastic cells immunoexpressed the CD31 monoclonal antibodies and factor VIII, through the identification of proteins expressed on the surface of endothelial cells. The Ki67 cell proliferation marker was positive in approximately 10% of the neoplastic cells, demonstrating a high degree of malignancy. Hemangiosarcoma in swine species has already been identified in several organs and tissues; however, to date, no study has demonstrated the diagnosis of this condition on the skin of the scrotum, as reported in this study. Therefore, it is expected that this report will contribute to the knowledge of the frequency of neoplasms in swine species.

Na espécie suína os tumores são pouco diagnosticados devido a curta vida útil dos animais de produção. Normalmente não causam sinais clínicos, sendo, muitas vezes, encontrados no momento do abate. Um reprodutor com dois anos de idade, da raça Large White, utilizado no manejo reprodutivo de uma granja, sem histórico de problemas pré-existentes, foi examinado em função de lesões na pele da bolsa escrotal. Foram coletadas amostras de segmentos de pele contendo lesões para o diagnóstico histopatológico e imunohistoquímico. Microscopicamente os nodos em bolsa escrotal consistiam em neoplasias mal demarcadas, altamente celulares, expansivas e multifocalmente invasivas composta por endoteliócitos imaturos organizados em formações neovasculares. As células tumorais eram pleomórficas, levemente ovais a fusiformes com citoplasma eosinofílico e núcleos hipercromáticos e com um a três nucléolos. Todos os nódulos analisados foram compatíveis com hemangiossarcoma. Para a quantificação da angiogênese tecidual, após a avaliação imunohistoquímica, as células neoplásicas imunoexpressaram os anticorpos monoclonais CD31 e Fator VIII, através da identificação de proteínas expressas na superfície das células endoteliais. Observou-se o marcador de proliferação celular Ki67 positivo em aproximadamente 10% das células neoplásicas, demonstrando um alto grau de malignidade. O hemangiossarcoma na espécie suína já foi identificado em vários órgãos e tecidos, mas, até o momento, nenhum trabalho demonstrou o diagnóstico na pele da bolsa escrotal, como reportado, ineditamente, neste estudo. Face o exposto, espera-se que este relato contribua para a frequência de neoplasias encontradas na espécie suína.

Canine splenic tumors: Histopathological study of 9 cases in Uruguay, 2019-2020

There are no reports of what kind of spleen tumors have developed within a certain period of time in Uruguay. Therefore, we investigated spleen tumors that were surgically resected and brought into our laboratory for a year (2019-2020). As a result, 9 splenic tumors were observed. Hemangiosarcomas occurred at the highest incidence in 6 of 9 cases. In addition, 1 case each of lymphoma, fibrosarcoma, and perivascular wall tumor was observed. Furthermore, the perivascular wall tumor, which has not been reported so far, was observed in a seven years-old female Cocker Spaniel.(AU)

Adenocarcinoma em glândula lacrimal de equino / Equine lacrimal gland adenocarcinoma

Background: Lacrimal gland adenocarcinoma is an extremely rare malignant neoplasm, with few descriptions in the literature. Therefore, its etiology and treatment are not well understood. The present study aims to report the case of an equine histologically diagnosed with lacrimal gland adenocarcinoma in the lower eyelid region and third eyelid treated by surgical excision and intralesional chemotherapy. Case: A 17-year-old male mixed-breed equine weighing 300 kg was treated in the large animal clinic and surgery sector of the Federal University of Santa Catarina in the city of Curitibanos, Santa Catarina, Brazil. The equine revealed an alert and docile temperament without considerable physiological changes in the physical examination. In the evaluation of the right eye, a tumor mass was observed in the region of the lacrimal gland adhered to the third eyelid and lower eyelid, with a light red ulcerated appearance approximately 7 cm in diameter. Therefore, the surgical excision of the adhered tumor mass was performed, with the subsequent intralesional application of 2 mL of Vincristine Sulfate. In the histopathological evaluation following the surgical excision of the tumor mass, yellowish-white fragments of irregular nodules were observed measuring from 3.5×2.0×1.7 cm to 2.0×0.5×0.3 cm, in addition to microscopy focus clusters of weakly basophilic neoplastic glandular cells, some with a randomly arranged lacy aspect, forming disorganized acinar structures and others showed marking islands of the cells organized in a palisade shape by vascular delicate stroma. The neoplastic cells presented anisocytosis, anisokaryosis, prominent nucleoli sometimes binucleated and with basophilic intracytoplasmic secretory material, delimited by scarce connective tissue. In some areas, there were small foci of infiltrated lymphocytes and plasmocytes and areas of necrosis. The mass was surrounded by connective tissue, where red blood vessels were found outside the vessels (hemorrhage), and mitoses were observed 2 per field at high magnification (40x). After the surgical procedure, it was not possible to follow up and reassess of the patient, so there is no clarification on the possibility of tumor recurrence. Discussion: The case reported is uncommon, being only the second report of adenocarcinoma in the equine lacrimal gland. Therefore, there are few descriptions in the literature about its defined etiology and the best treatment method, although, surgical excision is the method of choice because it is a tumor of high recurrence and invasiveness. In this case, we opted for the exeresis of the tumor mass and later application of chemotherapy, a treatment that was relatively effective, to avoid recurrence and the failure of the technique. In these cases, monitoring the animal after the procedure is recommended, evaluating whether there was tumor recurrence, although this was not possible in the present possible. The third eyelid, lacrimal, and zygomatic salivary glands may be sources of intraorbital neoplasms. These neoplastic processes may have similar histological and behavioral characteristics, and their differentiation is, therefore, problematic. These structures may be differentiated based on the anatomical location, however, clinical appearance and symptoms are identical in most cases. Adenocarcinoma in the equine lacrimal gland is a neoplasm considered rare, so it is important to emphasize an accurate diagnosis through histopathological analyses to differentiate it from other frequent orbital neoplasms in horses, allowing more information about this tumor and establishing different treatment methods.

Pólipo fibroepitelial atípico em córnea de um cão Lhasa Apso / Atypical fibroepithelial polyp in the cornea of a Lhasa Apso dog

Background: Fibroepithelial polyps are benign tumors of mesenchymal and ectodermal origin. Regarding the localization related to the cutaneous region, they may affect the eyelid and periocular area. In veterinary medicine, polyps located in the urethra of dogs and monkeys, vagina of bitches and on the skin have been described. Fibroepithelial polyps may present as single to multiple nodules, exophytic to pedunculated, usually arising on a smooth surface of a common base. The aim of this paper is to describe the ocular and histopathological changes of a corneal fibroepithelial polyp of recurrent character in a dog. Case: A 20-year-old Lhasa Apso dog, with a history of progressive corneal neoformation in the right eye for 4 months. Patient was submitted to routine ophthalmic evaluation. At biomicroscopy, a discrete mucopurulent discharge was observed in the nasal corner, a nodule in the lower eyelid (± 3 mm), moderate conjunctival hyperemia, vascularization and corneal edema between 12 and 5 h, presence of a pinkish proliferative mass in 3 h, affecting the anterior stroma and opacity of the lens, Schirmer's Tear Test (STT) 20 mm/min and intraocular pressure (IOP) 10 mm/Hg. In the left eye, the STT and IOP were within normal range (17 mm/min and 11 mg/Hg, respectively) and at biomicroscopy only lens opacity was observed. Given the presence of the neoformation in the cornea, the patient underwent lamellar keratectomy to excise the mass and third eyelid flap. The tissue was then submitted to histopathology. The histopathological examination showed a proliferation of fibrous component with areas presenting reactive fibroblasts, with acidophilic cytoplasm and with little volume and slight neovascularization, presence of hyperplasia of the lining epithelium and cells with round to oval nuclei, with inconspicuous nucleoli, compatible with fibroepithelial polyp, without evidence of malignancy. After 18 months, the patient presented recurrence of the condition with a history of slow evolution (about ten months). The ophthalmic evaluation showed lesions very similar to the initial one, describing a recurrence of the lesion. Discussion: Corneal neoplasms are uncommon in dogs. The clinical findings in patients with ocular neoplasms include irregular to nodular masses, gray to reddish in color, and typically associated with a vascular supply. These features are related to the type of tumor and its degree of evolution. There are reports in the literature of ocular neoplasms such as squamous cell carcinoma, papilloma, melanocytoma, fibrosarcoma, hemangiosarcoma, melanoma, lymphoma. Related to fibroepithelial polyp with ocular involvement, there are rare reports in human literature and none in veterinary medicine. There is a human description of the presence of a polyp affecting the cornea associated with a corneal dermoid and e other cases of polyps of conjunctival origin. As far as treatment is concerned, the polyp should be surgically removed because of the possibility of recurrence, tissue metaplasia, or even transformation into a malignant tumor, as seen in the case reported here, in which even with surgical removal there was recurrence and metaplasia of the cells. Based on the histopathological findings, it can be concluded that this is a fibroepithelial polyp with a recidivating characteristic, not well described in the veterinary literature, with an atypical presentation affecting the cornea.