Follicular lipidosis in a dachshund dog.

BACKGROUND: Follicular lipidosis is a rare disease, having only been reported in six Rottweiler dogs. The diagnosis of follicular lipidosis is confirmed by histopathological examination of the affected skin. OBJECTIVE: To report a case of follicular lipidosis in a dachshund dog. ANIMALS: A 13-month-old female dachshund dog, with hypotrichosis on the head and cervical region from 10 months of age. METHODS: Histological examination of skin biopsy specimens. RESULTS: Histological examination revealed basket weave orthokeratosis, ballooning of matrix cells and external root sheath keratinocytes. CLINICAL IMPORTANCE: This case report highlights the importance of including follicular lipidosis among the differential diagnoses of noninflammatory and nonhormonal cutaneous lesions in dachshund presented with hair loss.

Clinical, cytologic, and histologic features of a mammary micropapillary carcinoma in a dog.

Mammary invasive micropapillary carcinoma is a rare variant of mammary carcinoma that was recently recognized in dogs. The cytologic features and biologic behavior of such neoplasms in dogs have not yet been widely discussed in the veterinary literature. We report the clinical, cytologic, and histologic features of a canine micropapillary carcinoma in a 13-year-old female mongrel dog. The mammary region presented with extreme local pain, severe edema and erythema, and multifocal epidermal ulceration, which is typical for an inflammatory mammary carcinoma. Fine-needle aspirates were highly cellular and consisted of individual cells and papillary cell clusters with characteristics of malignant epithelial cells. Histologic examination revealed neoplastic cells arranged in small papillae without fibrovascular cores, sometimes inside clear lymphatic spaces, indicating lymphovascular invasion. Regional lymph node evaluation revealed metastatic cells. Due to deteriorating clinical condition the dog was euthanatized 5 months after mastectomy. At necropsy, metastatic neoplastic mammary cells were found in popliteal and mediastinal lymph nodes, the right femoral biceps muscle, liver, heart, lungs, and urinary bladder.

Exame citológico em medicina veterinária: estudo retrospectivo de 11.468 casos (1994-2008) / Cytological examination in veterinary medicine: Retrospective study of 11.468 cases (1994-2008)

Foi realizado um estudo retrospectivo dos resultados dos exames citológicos provenientes dos arquivos do Serviço de Citopatologia do Laboratório de Patologia Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista, Botucatu, São Paulo, entre janeiro de 1994 e dezembro de 2008. Do total de 139.986 animais atendidos no Hospital Veterinário da instituição, 11.468 (8,2%) foram encaminhados para exame citológico. Desses diagnósticos, 57,28% corresponderam a lesões neoplásicas, 19,28% a lesões inflamatórias e 14,79% a processos não neoplásicos (imunológicos, degenerativos, hiperplásicos ou displásicos). Não foi possível concluir o diagnóstico por meio do exame citológico em 7,28% dos casos e não haviam informações diagnósticas registradas em 1,37% dos casos. Dentre os animais que mais receberam indicação para exame citológico destacaram-se os caninos (92,06%), seguidos pelos felinos (4,08%), bovinos (1,77%) e equinos (1,30%). Lesoes neoplásicas foram as mais comumente observadas e foram mais prevalentes nos cães (59,18%), afetando principalmente animais com idade média de 119,60 meses e principalmente fêmeas (61,61%). O incremento anual observado ao longo dos 15 anos de aplicação da citologia demonstra que o exame citológico é um método de suma importância para confirmar, sugerir ou afastar o diagnóstico de diversas afecções, inclusive neoplasia, em todas as espécies animais.

A retrospective study was conducted over the results of cytological examination in the files of the Department of Cytopathology, Laboratory of Animal Pathology, School of Veterinary Medicine and Animal Science, São Paulo State University, Botucatu, SP, Brazil, from January 1994 to December 2008. Out of 139,986 animals referred to the teaching Veterinary Hospital, 11,468 (8.2%) were submitted to cytological examination. From these animals, 57.28% had a neoplastic lesion, 19.28% had inflammatory lesions, and 14.79% had non-neoplastic processes (immune-mediated, degenerative, hyperplastic, or dysplastic condition). By means of cytology, 7.28% of the cases were unable to be diagnosed, and there was no recorded diagnostic information in 1.37% of cases. The species that more commonly had samples submitted to cytology was the dog (92.06%), followed by cats (4.08%), cattle (1.77%), and horses (1.30%). As to the predominance of the observed processes, greater importance was given to neoplastic lesions. These were prevalent in dogs (59.18%), with a mean age of 119.60 months, and affecting mainly females (61.61%). The annual increase observed over the 15 years of application of cytology demonstrates that the cytological examination is a method of great importance to confirm, suggest, or exclude the diagnosis of various diseases, including cancer, in all animal species.

Spontaneous canine transmissible venereal tumor: association between different phenotypes and the insertion LINE-1/c-myc / Tumor venéreo transmisible canino espontáneo: asociación entre diferentes fenotipos y la inserción LINE -1/c-myc / Tumor venéreo transmissível canino espontâneo: associação entre diferentes fenótipos e a inserção LINE-1/c-myc

Objective: this study aimed to evaluate the LINE-1 transposon inserted in c-myc gene as a specific genetic alteration in cells of spontaneous canine Transmissible Venereal Tumor (TVT) with either lymphocytoid or plasmacytoid phenotypes. Methods: tumoral biopsies from 35 dogs were collected by puncture or exfoliation. Polymerase Chain Reaction (PCR) was carried out with primers myc.s and LINE. A, specific to the LINE-1 segment to detect the presence of LINE-1/c-myc molecular marker. Results: sequence alignment of DNA samples from lymphocytoid and plasmacytoid TVT cells did not show polymorphisms, and the comparison with sequences from the GenBank identified them as a LINE-1/c-myc rearrangement. Conclusions: considering the aggressive nature of the plasmacytoid phenotype, there is no apparent relation between LINE-1/c-myc and the malignancy of TVT. Further studies are needed to establish molecular differences associated with the aggressiveness of the various phenotypes of canine TVT.

Objetivo: evaluar la expresión del trasposón LINE-1 insertado en el oncogén c-myc como una alteración genética específica en células de Tumor Venéreo Transmisible canino espontáneo con fenotipos linfocitoideos o plasmocitoideos. Métodos: se tomaron muestras citológicas de 35 caninos naturalmente afectados por Tumor Venéreo Transmisible (TVT), separándolas en dos grupos de acuerdo al fenotipo predominante. La identificación del marcador molecular LINE-1/c-myc fue posible mediante la técnica de Reacción en Cadena de la Polimerasa (PCR) usando los primers myc.s y LINE. A, específicos para el segmento LINE-1. Resultados: el resultado del alineamiento de las secuencias obtenidas a partir del DNA de cada uno de los fenotipos de TVT no presentó variación entre ellos y al compararlas con el alineamiento de otras secuencias depositadas en el GenBank, pudo observarse que se trata de un reordenamiento LINE- 1/c-myc. Conclusiones: teniendo en cuenta la naturaleza agresiva del fenotipo plasmocitoide, se estableció que no hay polimorfismo genético entre los grupos analizados, siendo necesario realizar nuevos estudios tendientes a establecer diferencias moleculares asociadas con la agresividad de los diferentes fenotipos del TVT canino.

Objetivo: foi avaliado o elemento de transposição LINE-1 inserido no gene c-myc como alteração genética específica nas células do TVT espontâneo canino nos grupos fenotípicos previamente classificados como linfocitóide e plasmocitóide. Métodos: amostras da lesão de 35 cães foram colhidas por punção ou esfoliação. Para identificar o marcador molecular LINE-1/c-myc nas amostras foi utilizada a técnica de Reação em Cadeia da Polimerase empregando-se os primers myc.s e LINE. A, específicos para o segmento LINE-1. Resultados: o resultado do alinhamento das sequências obtidas das amostras de DNA das células de TVT linfocitóide e plasmocitóide não apresentou polimorfismos e, por meio do alinhamento com outras sequências depositadas no GeneBank, identificou-se que trata-se do rearranjo LINE-1/c-myc. Conclusões: parece não haver relação entre este aspecto molecular analisado com a agressividade do tumor.

Sebaceous metaplasia in a canine mammary gland non-infiltrative carcinoma with myoepithelial component.

Sebaceous metaplasia in canine mammary tumors is a rare condition with only 1 case documented. The current study describes a case of sebaceous metaplasia in a mammary gland carcinoma of an 8-year-old intact, nulliparous female Poodle dog with a subcutaneous tumor located in the left fifth mammary gland. The lesion measured 0.7 cm × 0.5 cm × 0.6 cm in diameter, was firm, circumscribed, painless, non-haired, and non-ulcerated, and did not adhere to deep tissues. The cut surface was non-lobulated, non-encapsulated, whitish to gray, and opaque. Histological evaluation revealed 3 different populations of cells: the first was composed of columnar to cuboidal malignant epithelial cells arranged in intraductal papillary projections, the second of myoepithelial cells associated with a myxoid stroma, and the third presenting sebaceous metaplasia similar to those previously described in both human and veterinary medicine.

Extramedullary hematopoiesis in a case of benign mixed mammary tumor in a female dog: cytological and histopathological assessment.

BACKGROUND: Extramedullary hematopoiesis (EMH) is defined as the presence of hematopoietic stem cells such as erythroid and myeloid lineage plus megakaryocytes in extramedullary sites like liver, spleen and lymph nodes and is usually associated with either bone marrow or hematological disorders. Mammary EMH is a rare condition either in human and veterinary medicine and can be associated with benign mixed mammary tumors, similarly to that described in this case. CASE PRESENTATION: Hematopoietic stem cells were found in a benign mixed mammary tumor of a 7-year-old female mongrel dog that presents a nodule in the left inguinal mammary gland. The patient did not have any hematological abnormalities. Cytological evaluation demonstrated two distinct cell populations, composed of either epithelial or mesenchymal cells, sometimes associated with a fibrillar acidophilic matrix, apart from megakaryocytes, osteoclasts, metarubricytes, prorubricytes, rubricytes, rubriblasts, promyelocytes, myeloblasts. Histological examination confirmed the presence of an active hematopoietic bone marrow within the bone tissue of a benign mammary mixed tumor. CONCLUSIONS: EMH is a rare condition described in veterinary medicine that can be associated with mammary mixed tumors. It's detection can be associated with several neoplastic and non-neoplastic mammary lesions, i.e. osteosarcomas, mixed tumors and bone metaplasia.