Splenic myelolipoma in a dog / Mielolipoma esplênico em um cão

Myelolipoma is a benign neoplasm composed of mature adipocytes and hematopoietic elements. This tumor is rare in dogs and cats and can develop in several organs and tissues. This report describes a case of splenic myelolipoma in a dog characterizing its clinical-pathological and ultrasonography aspects. A 9-year-old, female, mixed-breed, castrated dog was referred to the veterinary hospital with increased abdominal circumference. Ultrasonography revealed splenomegaly with masses of not measurable dimensions along the entire length of the parenchyma. The spleen was removed, and a fragment was sent for histopathological analysis. Macroscopically, the spleen was enlarged, with irregularly nodular growths that project above the surface of the organ. Nodules were red with small yellow areas. Microscopically, the spleen was effaced by a well-demarcated and not encapsulated mass composed of histologically well-differentiated neoplastic adipose tissue with islands and nests of varying proportions of hematopoietic elements. Histological examination confirmed the diagnosis of myelolipoma. Myelolipomas are observed on ultrasound images as hyperechoic masses or nodules with homogeneous echo texture. Here, ultrasound appearance involved mixed echogenicity and heterogeneous echotexture, due to the mixture of fat and non-fatty material components of the tumor.(AU)

Mielolipoma é uma neoplasia composta por adipócitos maduros e elementos hematopoiéticos. Este tumor é raro em cães e gatos e pode se desenvolver em diversos órgãos e tecidos. Descreve-se um caso de mielolipoma esplênico em um cão caracterizando seu aspecto clínico-patológico e ultrassonográfico. Um canino, fêmea, castrada, SRD, de 9 anos de idade foi encaminhada para o Hospital Veterinário com um aumento na circunferência abdominal. A ultrassonografia abdominal revelou esplenomegalia com massas de dimensões imensuráveis em toda a extensão do parênquima. Foi realizada esplenectomia total e um fragmento do baço foi encaminhado para análise histopatológica. Macroscopicamente o baço estava aumentado de tamanho, com crescimentos nodulares irregulares que se projetam acima da superfície do órgão. Os nódulos eram vermelhos com pequenas áreas amarelas. Microscopicamente foi observada uma massa bem demarcada e encapsulada composta por tecido adiposo neoplásico bem diferenciado, com ilhas e ninhos de elementos hematopoiéticos de proporção variada. O diagnóstico foi confirmado pelo exame histopatológico. Mielolipomas são observados nas imagens ultrassonográficas como massas hiperecóicas ou nódulos com ecotextura homogênea. Neste caso, o achado ultrassonográfico mostrou ecogenicidade mista e ecotextura heterogênea, provavelmente devido à mistura dos componentes do tumor com material gorduroso e não gorduroso.(AU)

Hepatic myelolipomas in Callimico goeldii (Thomas, 1904) kept in captivity

Myelolipoma is an unusual benign neoplasm in veterinary medicine. This work intended to report the occurrence of hepatic myelolipomas in Neotropical primates of the Callimico goeldii species kept in captivity. These cases were diagnosed during necropsy in a survey on liver neoplasms in the period of 2004 to 2008. Two cases were found in adult male, and two in adult female animals. The diagnoses were obtained through data analysis of necropsy records, pathological examination of the cases, and histological confirmation. Three (75%) of the animals showed clinical signs of progressive weight loss, and two (50%) of them exhibited regional abdominal bloating. The livers had protrusions of pale yellow color on the surface of all lobes. Histologically, the tumors were formed by mature myeloid tissue with high hematopoietic cellularity, represented by the megakaryocytes and meroblastic cells and immature erythroblasts. We conclude that non-human primates of the Callimico goeldii species might have predisposition for liver myelolipoma, which are neoplasms that can lead to the failure and destruction of this organ.

Hepatic myelolipomas in Callimico goeldii (Thomas, 1904) kept in captivity

Myelolipoma is an unusual benign neoplasm in veterinary medicine. This work intended to report the occurrence of hepatic myelolipomas in Neotropical primates of the Callimico goeldii species kept in captivity. These cases were diagnosed during necropsy in a survey on liver neoplasms in the period of 2004 to 2008. Two cases were found in adult male, and two in adult female animals. The diagnoses were obtained through data analysis of necropsy records, pathological examination of the cases, and histological confirmation. Three (75%) of the animals showed clinical signs of progressive weight loss, and two (50%) of them exhibited regional abdominal bloating. The livers had protrusions of pale yellow color on the surface of all lobes. Histologically, the tumors were formed by mature myeloid tissue with high hematopoietic cellularity, represented by the megakaryocytes and meroblastic cells and immature erythroblasts. We conclude that non-human primates of the Callimico goeldii species might have predisposition for liver myelolipoma, which are neoplasms that can lead to the failure and destruction of this organ.(AU)

Mielolipoma de adrenal funcional em um cão / Functional adrenal myelolipoma in a dog

Background: Myelolipomas are benign tumors composed of a mixture of fat and hematopoietic tissue similar to the bone marrow. They are rare tumors in humans and dogs, and occur generally in the spleen, liver, spinal canal and in the adrenal glands. When they develop in the adrenal glands they feature non-secretory and endocrinologically inactive characteristics, usually without clinical signs or other dysfunctions. Thus, they are often an incidental finding during necropsy. This paper aims to describe a case of functional adrenal gland myelolipoma and spleen myelolipoma in a female dog with clinical signs and laboratory tests compatible with hyperadrenocorticism.Case: A 12 year-old female dog, undefined breed, was treated at the Hospital Unit for Companion Animals of the Pontifical Catholic University of Paraná (PUCPR), São José dos Pinhais, Paraná, Brazil, with polyuria, polydipsia, polyphagia, cutaneous hypotonia and central obesity. Blood tests showed hypercholesterolemia and increased alkaline phosphatase; urinalysis identified isostenuria with proteinuria; and ultrasound and MRI of the abdomen indicated right adrenomegaly, with heterogeneous characteristics, without invasion of attached blood vessels and splenic nodules. The low dose dexamethasone suppression test was performed which confirmed hyperadrenocorticism. The animal was submitted to adrenalectomy and splenectomy, and tissue specimens were obtained for histopathological examination, which revealed mature adipocytes and hematopoietic elements in different phases of maturation, compatible with adrenal and spleen myelolipoma. After surgical treatment, there was a progressive improvement of the clinical manifestations and laboratory abnormalities of hypercortisolemia, without recurrence during one year.[...](AU)

Mielolipoma de adrenal funcional em um cão / Functional adrenal myelolipoma in a dog

Background: Myelolipomas are benign tumors composed of a mixture of fat and hematopoietic tissue similar to the bone marrow. They are rare tumors in humans and dogs, and occur generally in the spleen, liver, spinal canal and in the adrenal glands. When they develop in the adrenal glands they feature non-secretory and endocrinologically inactive characteristics, usually without clinical signs or other dysfunctions. Thus, they are often an incidental finding during necropsy. This paper aims to describe a case of functional adrenal gland myelolipoma and spleen myelolipoma in a female dog with clinical signs and laboratory tests compatible with hyperadrenocorticism.Case: A 12 year-old female dog, undefined breed, was treated at the Hospital Unit for Companion Animals of the Pontifical Catholic University of Paraná (PUCPR), São José dos Pinhais, Paraná, Brazil, with polyuria, polydipsia, polyphagia, cutaneous hypotonia and central obesity. Blood tests showed hypercholesterolemia and increased alkaline phosphatase; urinalysis identified isostenuria with proteinuria; and ultrasound and MRI of the abdomen indicated right adrenomegaly, with heterogeneous characteristics, without invasion of attached blood vessels and splenic nodules. The low dose dexamethasone suppression test was performed which confirmed hyperadrenocorticism. The animal was submitted to adrenalectomy and splenectomy, and tissue specimens were obtained for histopathological examination, which revealed mature adipocytes and hematopoietic elements in different phases of maturation, compatible with adrenal and spleen myelolipoma. After surgical treatment, there was a progressive improvement of the clinical manifestations and laboratory abnormalities of hypercortisolemia, without recurrence during one year.[...]

Emprego da Histopatologia no Diagnóstico Diferencial de Lesões Nodulares Esplênicas em Cães Submetidos a Esplenectomia

O baço é um órgão híbrido, vascular e linfóide, de tamanho variável, associado a múltiplas funções, como armazenamento e filtração sanguínea e reciclagem de ferro. No entanto, a esplenectomia é um procedimento usual, principalmente nos casos de esplenomegalia, associada a frequente redução da sobrevida. Este estudo propõe a caracterização histopatológica das lesões nodulares esplênicas em cães esplenectomizados, com base em cortes corados por hematoxilina-eosina, considerando sua natureza e relevância em termos sistêmicos. Foram avaliados 178 nódulos esplênicos, 115 não neoplásicos e 63 neoplásicos. Predominaram cães entre 8 e 13 anos de idade, com destaque para cães das raças labrador e golden retriever. As lesões não neoplásicas compuseram 64,7% das amostras, com ênfase nos casos de hiperplasias nodulares, correspondendo a 34,82% das ocorrências. As neoplasias representaram 35,3% das condições, dentre as quais estão processos raros ou ainda não relatados em baço de cães, como um mielolipoma, um linfangioma e um angioma de células litorais. Em consonância com a literatura, o processo neoplásico mais diagnosticado foi o hemangiossarcoma, correspondendo a 21.34% das amostras. A escassez de métodos diagnósticos alternativos à histopatologia e o elevado risco de ruptura lesional e consequente hemoperitônio fundamentam a realização de esplenectomias em elevada proporção dos casos. No entanto, nossos achados indicam o predomínio de lesões benignas e fortalecem o esforço pelo desenvolvimento de métodos menos agressivos que a esplenectomia para o diagnóstico diferencial das lesões nodulares esplênicas.

The spleen is a hybrid, vascular and lymphoid organ, of variable size, associated with multiple functions, such as blood storage and filtration and iron recycling. However, splenectomy is a usual procedure, especially in cases of splenomegaly, resulting in frequent reduction in survival. This study proposes the histopathological characterization of splenic nodular lesions in splenectomized dogs, based on sections stained by hematoxylin-eosin, considering their nature and systemic relevance. 178 splenic nodules, 115 non-neoplastic and 63 neoplastic nodules were evaluated. Dogs between 8 and 13 years old predominated, especially dogs of the Labrador and Golden Retriever breeds. Non-neoplastic lesions made up 64.7% of the samples, with an emphasis on cases of nodular hyperplasia, corresponding to 34.82% of occurrences. Neoplasms represented 35.3% of the conditions, among which are rare or unreported processes in the spleen of dogs, such as myelolipoma, lymphangioma and littoral cell angioma. In line with the literature, the most frequently diagnosed neoplastic process was hemangiosarcoma, corresponding to 21.34% of the samples. The scarcity of alternative diagnostic methods to histopathology and the high risk of lesion rupture and consequent hemoperitoneum support the performance of splenectomies in a high proportion of cases. However, our findings indicate a predominance of benign lesions and strengthen the effort to develop less aggressive methods than splenectomy for the differential diagnosis of splenic nodular lesions.

Hemangioma and myelolipoma in the adrenal gland of a dog / Hemangioma e mielolipoma em glândula adrenal de cão

Background: Endocrine tumors are considered rare in veterinary medicine. Studies suggest that only one or two per cent of these are primary neoplasms of the adrenal glands. Concerning the histological classifi cation of these masses, the most frequently occurring malignant neoplasms in dogs are adenocarcinomas and pheochromocytomas and, among the benign tumors, adenomas are the most common. Although much rarer, hemangiomas, myelolipomas, among others, may also occur. Dogs with this kind of neoplasm could be asyntomatic or show gastrointestinal signs, pain and urinary tract infection. Adrenalectomy is the treatment of choice and could be curative in most cases. This paper reports a case of two concurrent benign, rare adrenal neoplasms in a dog, emphasizing the clinical signs, diagnosis and treatmentCase: An eight-year-old, male castrated Chow-chow, weighting twenty one kilograms, was admitted at the Veterinary Teaching Hospital of the Federal University of Rio Grande do Sul (UFRGS) with a history of intermittent vomiting and diarrhea since it was a puppy. Because of the chronicity and nonspecifi c signs, additional tests were requested. Abdominal ultrasonography showed a round mass, measuring approximately 3.7 cm x 3.2 cm, suggesting a neoplasm. Blood pressure was measured and the mean value was 152 mmHg. Laboratory tests included a complete blood count, albumin (31.62 g/L), ala

Background: Endocrine tumors are considered rare in veterinary medicine. Studies suggest that only one or two per cent of these are primary neoplasms of the adrenal glands. Concerning the histological classifi cation of these masses, the most frequently occurring malignant neoplasms in dogs are adenocarcinomas and pheochromocytomas and, among the benign tumors, adenomas are the most common. Although much rarer, hemangiomas, myelolipomas, among others, may also occur. Dogs with this kind of neoplasm could be asyntomatic or show gastrointestinal signs, pain and urinary tract infection. Adrenalectomy is the treatment of choice and could be curative in most cases. This paper reports a case of two concurrent benign, rare adrenal neoplasms in a dog, emphasizing the clinical signs, diagnosis and treatment.Case: An eight-year-old, male castrated Chow-chow, weighting twenty one kilograms, was admitted at the Veterinary Teaching Hospital of the Federal University of Rio Grande do Sul (UFRGS) with a history of intermittent vomiting and diarrhea since it was a puppy. Because of the chronicity and nonspecifi c signs, additional tests were requested. Abdominal ultrasonography showed a round mass, measuring approximately 3.7 cm x 3.2 cm, suggesting a neoplasm. Blood pressure was measured and the mean value was 152 mmHg. Laboratory tests included a complete blood count, albumin (31.62 g/L), al

Hemangioma e mielolipoma em glândula adrenal de cão / Hemangioma and myelolipoma in the adrenal gland of a dog

Background: Endocrine tumors are considered rare in veterinary medicine. Studies suggest that only one or two per cent of these are primary neoplasms of the adrenal glands. Concerning the histological classification of these masses, the most frequently occurring malignant neoplasms in dogs are adenocarcinomas and pheochromocytomas and, among the benign tumors, adenomas are the most common. Although much rarer, hemangiomas, myelolipomas, among others, may also occur. Dogs with this kind of neoplasm could be asyntomatic or show gastrointestinal signs, pain and urinary tract infection. Adrenalectomy is the treatment of choice and could be curative in most cases. This paper reports a case of two concurrent benign, rare adrenal neoplasms in a dog, emphasizing the clinical signs, diagnosis and treatment. Case: An eight-year-old, male castrated Chow-chow, weighting twenty one kilograms, was admitted at the Veterinary Teaching Hospital of the Federal University of Rio Grande do Sul (UFRGS) with a history of intermittent vomiting and diarrhea since it was a puppy. Because of the chronicity and nonspecific signs, additional tests were requested. Abdominal ultrasonography showed a round mass, measuring approximately 3.7 cm x 3.2 cm, suggesting a neoplasm. Blood pressure was measured and the mean value was 152 mmHg. Laboratory tests included a complete blood count, albumin (31.62 g/L), alanine aminotransferase (26.19 U/L), alkaline phosphatase (64.68 U/L), sodium (147 mmoL), potassium (4.5 mEq/L), fasting blood glucose (60.87 mg/dL), cholesterol (137.64 mg/dL), triglycerides (34.89 mg/dL), amylase (592 U/L), lipase (163 U/L), creatinine (0.67 mg/dL), and parasitologic exam of the feaces, which revealed no significant changes at all. An unilateral adrenalectomy was performed for diagnostic and therapeutic purposes. The patient was anesthetized and was placed in left lateral recumbency. An incision was made along the thirteenth rib, allowing an adequate visualization of the right adrenal. A careful dissection and ligation of vessels was performed, the gland was removed and sent for histopathology. The abdominal cavity was sutured routinely. Histopathological examination disclosed two fragments of benign tumors, namely myelolipoma and hemangioma. The animal had an excellent postoperative recovery, being given antibiotics, analgesics and daily dressings as treatment. In the follow-up reexamination only mucus persisted in the stool, however a diagnostic colonoscopy was not authorized by the owner. Discussion: Adrenalectomy represented both the definitive diagnostic and therapeutic methods of choice, since the growth of these masses could compromise adjacent organs. The open approach is the method used for adrenalectomy in veterinary patients, as opposed to people, where the laparoscopic surgery is generally chosen. In this report, we opted for an right paracostal incision to allow a better exposure and dissection of the adrenal gland in this medium-sized dog. There was no need for supplemental glucocorticoids in the postoperative period because these neoplasms are non-functioning, which represents a contraindication for its use. Therefore, total adrenalectomy was proven effective in the treatment of these two concurrent adrenal neoplasms, as supported by the postoperative course.

Mielolipoma adrenal bilateral em um cão / Bilateral adrenal myelolipoma in a dog

O presente relato descreve um caso de mielolipoma adrenal bilateral em uma cadela Poodle de 13 anos de idade. O cão morreu por peritonite séptica aguda, decorrente de ulceração e perfuração intestinal por corpo estranho linear. O neoplasma foi achado incidentalmente durante a necropsia. Macroscopicamente, as adrenais estavam redondas e com volume e aumentados. Ao corte elas eram friáveis, vermelho-amarronzadas, intercaladas por áreas branco-amareladas levemente proeminentes. Histologicamente, extensas áreas do parênquima continham adipócitos bem diferenciados, células hematopoéticas e macrófagos com hemossiderina, achados característicos de mielolipoma adrenal.(AU)

A case of bilateral adrenal myelolipoma in a 13-year-old female Poodle is reported. Acute septic peritonitis due to intestinal ulceration and perforation caused by a linear foreign body was the cause of death. The adrenal neoplasm was an incidental necropsy finding. The adrenal glands were grossly rounded, enlarged and friable, and had red-brownish parenchyma interwoven by slightly prominent white-yellowish foci. Histologically, the findings of differentiated adipocytes in large areas of the parenchyma, in association to hematopoietic cells and macrophages with hemosiderin were consistent with the diagnosis of adrenal myelolipoma.(AU)

Hemangioma and myelolipoma in the adrenal gland of a dog / Hemangioma e mielolipoma em glândula adrenal de cão

Background: Endocrine tumors are considered rare in veterinary medicine. Studies suggest that only one or two per cent of these are primary neoplasms of the adrenal glands. Concerning the histological classifi cation of these masses, the most frequently occurring malignant neoplasms in dogs are adenocarcinomas and pheochromocytomas and, among the benign tumors, adenomas are the most common. Although much rarer, hemangiomas, myelolipomas, among others, may also occur. Dogs with this kind of neoplasm could be asyntomatic or show gastrointestinal signs, pain and urinary tract infection. Adrenalectomy is the treatment of choice and could be curative in most cases. This paper reports a case of two concurrent benign, rare adrenal neoplasms in a dog, emphasizing the clinical signs, diagnosis and treatmentCase: An eight-year-old, male castrated Chow-chow, weighting twenty one kilograms, was admitted at the Veterinary Teaching Hospital of the Federal University of Rio Grande do Sul (UFRGS) with a history of intermittent vomiting and diarrhea since it was a puppy. Because of the chronicity and nonspecifi c signs, additional tests were requested. Abdominal ultrasonography showed a round mass, measuring approximately 3.7 cm x 3.2 cm, suggesting a neoplasm. Blood pressure was measured and the mean value was 152 mmHg. Laboratory tests included a complete blood count, albumin (31.62 g/L), ala

Background: Endocrine tumors are considered rare in veterinary medicine. Studies suggest that only one or two per cent of these are primary neoplasms of the adrenal glands. Concerning the histological classifi cation of these masses, the most frequently occurring malignant neoplasms in dogs are adenocarcinomas and pheochromocytomas and, among the benign tumors, adenomas are the most common. Although much rarer, hemangiomas, myelolipomas, among others, may also occur. Dogs with this kind of neoplasm could be asyntomatic or show gastrointestinal signs, pain and urinary tract infection. Adrenalectomy is the treatment of choice and could be curative in most cases. This paper reports a case of two concurrent benign, rare adrenal neoplasms in a dog, emphasizing the clinical signs, diagnosis and treatment.Case: An eight-year-old, male castrated Chow-chow, weighting twenty one kilograms, was admitted at the Veterinary Teaching Hospital of the Federal University of Rio Grande do Sul (UFRGS) with a history of intermittent vomiting and diarrhea since it was a puppy. Because of the chronicity and nonspecifi c signs, additional tests were requested. Abdominal ultrasonography showed a round mass, measuring approximately 3.7 cm x 3.2 cm, suggesting a neoplasm. Blood pressure was measured and the mean value was 152 mmHg. Laboratory tests included a complete blood count, albumin (31.62 g/L), al