Bilateral hibernomas in the femoral regions of a dog.

A 14-year-old intact male Chihuahua dog was presented with masses located between the biceps femoris and adductor muscles in both hind limbs. Based on histopathological, immunohistochemical, and ultrastructural findings, we diagnosed these masses as bilateral hibernomas in the femoral regions. The dog had no evidence of recurrence or metastasis of the hibernomas through a 4-month postoperative follow-up. This is apparently the first report of bilateral hibernomas in the femoral regions of a dog. Key clinical message: Bilateral hibernomas should be considered as a differential diagnosis for masses occurring in the femoral regions of dogs.

Hibernomes bilatéraux dans les régions fémorales d'un chien. Un chien Chihuahua mâle intact de 14 ans a été présenté avec des masses situées entre le biceps fémoral et les muscles adducteurs des deux membres postérieurs. Sur la base des résultats histopathologiques, immunohistochimiques et ultrastructuraux, nous avons diagnostiqué ces masses comme des hibernomes bilatéraux dans les régions fémorales. Le chien n'avait aucun signe de récidive ou de métastases des hibernomes au cours d'un suivi postopératoire de 4 mois. Il s'agit apparemment du premier rapport d'hibernome bilatéral dans les régions fémorales d'un chien.Message clinique clé:Les hibernomes bilatéraux doivent être considérés comme un diagnostic différentiel pour les masses survenant dans les régions fémorales des chiens.(Traduit par Dr Serge Messier).

Imaging diagnosis: CT characteristics of a retrobulbar hibernoma in a dog.

A 12-year-old female spayed Beagle was referred for investigation of exophthalmos. CT revealed a well-defined, retrobulbar mass causing rostro-dorsal displacement of the left globe. The mass had a mildly heterogeneous precontrast soft tissue attenuation with mild heterogeneous enhancement following iohexol administration. The mass was surgically removed en bloc with an orbital exenteration. Histopathology confirmed the mass to be a hibernoma, a benign tumor of brown adipose tissue. Hibernomas have CT characteristics consistent with both benign and malignant adipose tumors and may be underrecognized by radiologists.

Liver Lipoma in a Dog: Case Report and Literature Review.

Lipoma of the liver has not been reported in dogs. An 8 yr old spayed female Great Dane was referred for diagnostic workup of abdominal distention. Computed tomography showed fat-attenuating masses with negative attenuation values (variable between -60 to -40 Hounsfield units) and minimal contrast uptake within the left cranial abdomen. Left lateral and right medial liver lobectomies were performed to remove two liver masses. Histopathology showed large lipomas arising from within the hepatic parenchyma. Immunohistochemistry for smooth muscle actin was negative, consistent with true lipomas. The dog was euthanized 8 mo later because of causes likely unrelated to the liver lipoma. This is the first case report of lipoma in the liver of a dog. The purpose of this case report and brief literature review is to provide evidence that surgical excision of fat-attenuating masses within the liver that are consistent with lipoma using immunohistochemistry can be curative.

Chylothorax secondary to subcutaneous cervical lipoma in a dog.

An 8-year-old male neutered American English Coonhound was presented for a 2-day history of increased respiratory effort and rate with an occasional cough. Thoracic radiographs noted pleural effusion, which was chylous based on cytological and chemical evaluation. The dog also had a 2-year history of a slow growing fatty mass in the right cervical region. A CT scan confirmed the large cervical fat attenuating mass extending from the base of the skull to the cranial thorax and right axillary region with compression of vascular structures. Severe bilateral effusion and secondary pulmonary atelectasis was noted within the thoracic cavity. It was elected to surgically remove the cervical mass and place a PleuralPort within the thoracic cavity. The mass was diagnosed as a lipoma and its removal led to rapid and complete resolution of chylothorax. Based on the literature search, this is the first case report of chylothorax secondary to a cervical mass or subcutaneous lipoma.

Primary well differentiated hepatic liposarcoma in a meerkat (Suricata suricatta).

A 9-year-old female meerkat (Suricata suricatta) succumbed to progressive abdominal distension, anorexia, and depression. Necropsy revealed an extensively distended abdomen with ascites and markedly enlarged liver. The liver had multiple yellowish masses and displaced the thoracic cavity and abdominal organs. There was no evidence of metastatic lesions based on the gross and microscopic findings. Histologically, the liver mass was composed of locally invasive well-differentiated neoplastic adipocytes with Oil Red O-positive lipid vacuoles. Immunohistochemistry revealed positive immunoreactivity to vimentin, S-100 and negative to pancytokeratin, desmin, smooth muscle actin (SMA), ionized calcium-binding adapter molecule 1 (IBA-1). Thus, the primary well differentiated hepatic liposarcoma was diagnosed based on gross, histological and immunohistochemistry results.

Caudal thigh intermuscular lipomas in dogs: Anatomic review and approach to surgical excision.

The surgical approach for excision of caudal thigh intermuscular lipomas (IML) in dogs is described with relevant anatomy and short-term outcomes reported. Medical records were reviewed to identify dogs that underwent IML excision between 2015 to 2019. Signalment, location of the lipoma, pre-operative diagnostic tests, histopathology results, use of a closed-suction drain, and follow-up information including drain and suture removal were recorded. Mean age of patients in this study was 8.7 years. Multiple breeds were affected and there was no predilection for either left or right hind limb. Pre-operative diagnostic tests included fine-needle aspirate, radiography, peripheral ultrasonography, and/or computed tomography scan. In 45% (5/11) of the cases, a closed suction drain was placed. All masses removed were deemed grossly consistent with a lipoma by the attending clinician and 5 were confirmed by histopathology. No complications were noted in any case. Removal of caudal thigh IML requires careful identification of and dissection around the sciatic nerve, which is easily achieved with appropriate knowledge of the relevant anatomy and surgical approach.

Lipomes intermusculaires de la cuisse caudale chez le chien : revue anatomique et approche de l'exérèse chirurgicale. L'approche chirurgicale pour l'excision des lipomes intermusculaires (IML) de la cuisse caudale chez le chien est décrite avec l'anatomie pertinente et les résultats à court terme rapportés. Les dossiers médicaux ont été examinés pour identifier les chiens qui ont subi une excision IML entre 2015 et 2019. Le signalement, l'emplacement du lipome, les tests de diagnostic préopératoire, les résultats histopathologiques, l'utilisation d'un drain à aspiration fermé et les informations de suivi, y compris le retrait du drain et des sutures, ont été enregistrés. L'âge moyen des patients de cette étude était de 8,7 ans. Plusieurs races ont été affectées et il n'y avait aucune préférence pour la latéralité gauche ou droite. Les tests diagnostiques préopératoires comprenaient une aspiration à l'aiguille fine, une radiographie, une échographie périphérique et/ou une tomodensitométrie. Dans 45 % (5/11) des cas, un drain aspirant fermé a été mis en place. Toutes les masses enlevées ont été jugées grossièrement compatibles avec un lipome par le clinicien traitant et cinq ont été confirmées par histopathologie. Aucune complication n'a été notée dans tous les cas. L'ablation d'IML de la cuisse caudale nécessite une identification précise et une dissection autour du nerf sciatique, ce qui est facilement réalisé avec une connaissance appropriée de l'anatomie et de l'approche chirurgicale.(Traduit par Dr Serge Messier).

Subcutaneous, abdominal, and thoracic encapsulated fat necrosis in bowhead whales Balaena mysticetus from Alaska, USA.

We describe a case series of encapsulated fat necrosis with subcutaneous, abdominal, and thoracic locations in 7 subsistence-harvested bowhead whales Balaena mysticetus. Masses had a variably-dense fibrous capsule surrounding necrotic adipocytes and calcium salts (saponification). One animal also had prior concussive injury, pleural fibrosis, and hepatic lipoma; the other animals had no significant findings. The described condition is uncommon in bowhead whales, with 7/575 (1.2%) observed from 1996 to 2015. The exact mechanisms of development of encapsulated fat necrosis in bowhead whales remain to be determined. Encapsulated fat necrosis has been reported in other baleen whales, humans, and cows. It is usually an incidental finding during post-mortem examination that needs to be differentiated from neoplastic and inflammatory lesions, as the latter may have public health implications. Assessment of further cases in bowhead whales and other baleen whales is warranted to better understand their pathogenesis.

Equine small intestinal angiomatosis.

Multiple red, raised nodules multifocally distributed along the serosal surface of the normal and the nonviable jejunum were identified in a 24-year-old neutered male horse undergoing surgery for removal of the strangulating lipoma around the jejunum. Histologically, these nodules consisted of many significantly and variably dilated, blood-filled vascular channels lined by a single layer of flattened, well-differentiated endothelial cells with occasional thrombi within a mildly thickened fibrous stroma. A diagnosis of intestinal angiomatosis was proposed. To the best of the authors' knowledge, this is the second report of small intestinal angiomatosis in a horse.

Angiomatose du petit intestin équin. De multiples nodules rouges surélevés distribués de manière multifocale le long de la surface séreuse du jéjunum viable et non-viable furent identifiés chez un cheval mâle castré âgé de 24 ans soumis à une chirurgie pour le retrait d'un lipome étranglant autour du jéjunum. Histologiquement, ces nodules consistaient en de nombreux canaux vasculaires remplis de sang dilatés de manière significative et variable, et tapissés par une couche unique de cellules endothéliales aplaties et bien différenciées avec à l'occasion des thrombi à l'intérieur d'un stroma fibreux légèrement épaissi. Un diagnostic d'angiomatose intestinale fut proposé. Au meilleur de la connaissance des auteurs, ceci constitue le deuxième rapport d'angiomatose du petit intestin chez un cheval.(Traduit par Dr Serge Messier).

Clinical management of lipomas in dogs under primary care in the UK.

Lipomas are relatively common and biologically benign masses of mesenchymal origin consisting of adipocytes. This study reports benchmark data on the clinical management and outcomes of lipomas in dogs under UK primary veterinary care. The study used a cross-sectional analysis of cohort clinical data from dogs that were under veterinary care at practices participating within VetCompass from January 1, 2013 to December 31, 2013. Descriptive and analytic statistics characterised the clinical management and outcomes following presumptive lipoma diagnosis. The study included 2765 lipoma cases from 384 284 dogs under UK veterinary care during 2013. Diagnostics included fine needle aspirate in 1119 (40.5 per cent) cases, biopsy in 215 (7.8 per cent) cases and diagnostic imaging in 11 (0.4 per cent) cases. Overall, 525 (19.0 per cent) cases were managed surgically. Of the surgical cases, 307 (58.5 per cent) solely had mass removal whilst 218 (41.5 per cent) included another procedure during the same surgical episode. A surgical drain was placed during surgery in 90 (17.1 per cent) cases. Wound breakdown was reported in 14 (2.7 per cent) surgical procedures. Wound infection followed surgery in 11 (2.1 per cent) dogs. The findings provide veterinarians with an evidence base that benchmarks how lipoma cases are currently managed in the UK, but these results do not necessarily reflect optimal management or best practice.

Computed tomographic and ultrasonographic diagnosis with successful excision of a lipoma in a shusui koi (Cyprinus carpio).

CASE DESCRIPTION: A client-owned 12-year-old 10.3-kg (22.7-lb) female shusui koi (Cyprinus carpio) was evaluated because of an ulcerated mass on the left body wall, hyporexia, and decreased activity. CLINICAL FINDINGS: The patient was anesthetized with a solution of eugenol in water for all examinations and procedures. An approximately 7 × 5-cm smooth, raised, ulcerated, and firm mass was present ventral and lateral to the dorsal fin on the left body wall. Whole-body CT images obtained before and after contrast administration revealed an encapsulated, homogeneous, fat-opaque mass within the muscle. The mass was fat echoic with poor vascularity on ultrasonographic examination. Histologic evaluation of an ultrasound-guided needle biopsy specimen was suggestive of a lipoma. TREATMENT AND OUTCOME: The mass was excised, and the fish was placed in water with 0.3% salinity for 3 weeks after surgery. Postoperative antimicrobial administration was not indicated, and additional postoperative analgesic administration was considered impractical. The patient had noticeable improvement in appetite and activity with no indication of discomfort immediately following surgery. Five weeks after surgery, the incision site had healed with minimal scarring, and evaluation of CT images revealed no evidence of mass regrowth or regional osteomyelitis. CLINICAL RELEVANCE: Antemortem evaluation and diagnosis of a lipoma in a teleost with subsequent excision was described. This report highlighted the logistic challenges associated with anesthesia, advanced diagnostic imaging, and surgery in fish and showed that they can be successfully overcome so that high-level medical care can be provided to such patients.

Cytologic appearance of hibernoma in two dogs.

Hibernomas are rare benign tumors of brown fat (adipose tissue) that have been reported in several different species. The cytologic characterization of these tumors has not been described in dogs. In this case report, we describe two dogs with hibernomas, focusing on the cytologic appearance of these unique neoplasms. Both cytologic specimens were highly cellular and predominated by vacuolated neoplastic cells with no evidence of concurrent inflammation. The cells contained a moderate to large number of variably sized cytoplasmic vacuoles, with occasional, irregularly shaped pink granular material. Most cells contained a single nucleus; however, cells displayed moderate anisokaryosis. A biopsy with histologic examination was performed in both cases, confirming the cytologic suspicion of hibernoma. Immunohistochemistry revealed that both tumors were positive for UCP1 and vimentin, and negative for cytokeratin. Hibernoma is an important differential diagnosis in dogs with conjunctival and periocular swellings that exfoliate numerous, mildly atypical, vacuolated cells.

Canine retrobulbar lipoma excision through a ventral transpalpebral anterior orbitotomy.

A 5-year-old spayed female German shepherd dog was referred for diagnostic evaluation and treatment of progressive exophthalmos, conjunctival hyperemia, and protrusion of the third eyelid of the left eye. Computed tomography revealed a retrobulbar mass of the orbit, exhibiting radio attenuation consistent with adipose tissue and well-defined margins. No evidence of metastasis was detected on thoracic radiographs or abdominal ultrasound. Cytological evaluation of ultrasound-guided fine-needle aspirates was inconclusive. A ventral transpalpebral anterior orbitotomy approach facilitated excision of the abnormal retrobulbar tissue. Histopathology revealed mature adipose cells compatible with a lipoma. The patient regained normal appearance and function 3 months after surgery. Key clinical message: While rare, consider a lipoma as a differential diagnosis for a retrobulbar mass. The ventral transpalpebral orbitotomy has been described in only 3 cases in the veterinary literature, and this is the only known report of utilizing this approach for excision of a neoplastic condition.

Excision d'un lipome rétrobulbaire canin à travers une orbitotomie antérieure ventrale transpalpébrale. Une chienne Berger Allemand stérilisée âgée de 5 ans fut référée pour évaluation diagnostique et traitement d'exophtalmie progressive, d'hyperémie conjonctivale et de protrusion de la troisième paupière de l'oeil gauche. Un examen par tomodensitométrie révéla une masse rétrobulbaire de l'orbite, montrant de la radioatténuation compatible avec du tissu adipeux et des bordures bien définies. Aucune évidence de métastase ne fut détectée sur les radiographies thoraciques ou une échographie abdominale. Une évaluation cytologique d'aspirations écho-guidées à l'aiguille fine était non-concluante. Une orbitotomie antérieure par approche transpalpébrale ventrale facilita l'excision du tissu rétrobulbaire anormal. L'examen histopathologique mis en évidence des cellules adipeuses matures compatibles avec un lipome. Le patient retrouva une apparence et une fonction normales 3 mois après la chirurgie.Message clinique important :Bien que rare, un lipome doit être considéré comme un diagnostic différentiel lors de masse rétro-bulbaire. L'orbitotomie ventrale transpalpébrale a été décrite dans seulement trois cas dans la littérature vétérinaire, et le présent rapport est le seul connu utilisant cette approche pour l'excision d'une condition néoplasique.(Traduit par Dr Serge Messier).

Computed tomographic findings, surgical management and postoperative outcomes of large intermuscular lipomas in the hindlimb of 11 dogs.

OBJECTIVE: Lipomas are benign adipose tissue tumours of mesenchymal origin and can originate in various locations. Intermuscular lipomas in the thigh can cause substantial hindlimb expansion in the dog. We describe the computed tomography findings, surgical management and the outcomes of 11 dogs with large intermuscular lipomas of the hindlimb. DESIGN: Retrospective case series. METHODS: Medical records between 2009 and 2019 of dogs presenting to The Animal Hospital at Murdoch University were reviewed. Inclusion criteria included dogs with a histologically confirmed, large hindlimb lipoma that was surgically excised following preoperative computed tomography (CT) imaging. RESULTS: CT with intravenous contrast revealed a well-defined, smoothly marginated, fat attenuating mass with minimal vascularity, separating the muscle bellies of the caudal hindlimb. The mass was often in close proximity to the femoral artery and vein. All lipomas were marginally excised. At surgery, some lipomas were intimately associated with the sciatic nerve and some showed infiltration of, or attachment to, neighbouring muscle that could be excised en bloc with the lipoma. Postoperative closed-suction wound drainage was used in 6 of 11 dogs. One dog required revision surgery due to partial wound dehiscence. Long-term follow-up with owners reported good postoperative function of the affected hindlimb in all dogs. One dog developed an infiltrative lipoma in the same location 22 months post-excision. CONCLUSION: Preoperative CT allowed a presumptive diagnosis of intermuscular lipoma and facilitated surgical planning for marginal excision. Large intermuscular lipomas of the hindlimb can be safely excised with minimal short-term complications, good long-term functional outcome and low likelihood of recurrence.

Retrospective study of canine cutaneous tumors in Japan, 2008-2017.

Cutaneous tumors are commonly found in dogs. To date, few studies have investigated the epidemiology of canine cutaneous tumors in Asian countries. The present study aims to report the prevalence of canine cutaneous tumors in Japan, and assess the association of breed, age, sex, and anatomical locations with the development of common tumor types. A total of 1,435 cases of cutaneous tumors were examined, of which 813 (56.66%) cases were malignant, and 622 (43.34%) were benign. Soft tissue sarcomas (18.40%), mast cell tumor (16.24%), lipoma (9.69%), hair follicle tumors (9.34%), and benign sebaceous tumors (8.50%) outnumbered the other tumor types. Tumors were commonly found on the head (13.87%), hindlimb (10.52%), forelimb (8.01%), chest (5.78%), and neck (5.57%). The risk of developing cutaneous tumors increased significantly in dogs aged 11-year and above (P<0.001). Mixed-breed dogs (14.63%), Miniature Dachshund (9.90%), and Labrador Retriever (8.01%) were the three most presented breeds; while Boxer, Bernese Mountain Dog, and Golden Retriever had an increased risk of cutaneous tumor development in comparison to mixed-breed dogs (P<0.05). Epidemiological information from the present study will serve as a useful reference for regional veterinarians to establish a preliminary diagnosis of canine cutaneous tumors.

Multiple Infiltrative Intraosseous Lipomas in the Appendicular Skeleton of a Rose-breasted Cockatoo (Eolophus roseicapilla) with a Humeral Fracture.

A 9-year-old female rose-breasted cockatoo (Eolophus roseicapilla) was presented for a humeral fracture. At presentation, the bird was severely lethargic and obese. On physical examination, an open right humeral fracture, healed left ulnar fracture, and intertarsal joint swelling were present. Results of hematologic testing and biochemical analysis revealed severe leukocytosis with heterophilia and increased creatine kinase and aspartate aminotransferase activities consistent with musculoskeletal lesions. Radiographs confirmed a right humeral fracture and showed severe polyostotic lytic and expansile lesions of the appendicular skeleton, as well as an enlarged hepatic silhouette. Surgical repair of the fracture was attempted, but the bird died during the procedure. Postmortem examination revealed severe bone deformities involving the fractured humerus, both ulnas, and the left tibiotarsus. Histologic findings were consistent with multiple intraosseous lipomas of the long bones and severe hepatic lipidosis. To our knowledge, this is the first report of multiple intraosseous lipomas in a bird.

[Intramural jejunal lipoma in the small intestine of a young Arabian horse causing invagination of the jejunum]. / Intramurales Lipom im Jejunum als Ursache für eine Invagination bei einer jungen Araberstute.

A 2-year-old Arabian horse was presented with severe colic symptoms. During explorative laparotomy, a jejuno-jejunal invagination secondary to a submucosal intestinal mass was detected. The involved jejunal segment was surgically removed and an end-to-end anastomosis was created. Opening the specimen demonstrated the presence of a nodular mass on the head of the intussusceptum, measuring 10 cm in diameter, and almost completely obliterating the intestinal lumen. Additionally, a severe hyperemia of the jejunal mucosa was visible. Histological examination, which revealed a well-demarcated mass in the submucosa of the jejunum consisting of well-differentiated adipocytes, led to the diagnosis of an intramural lipoma. The small intestinal mucosa displayed mild to moderate signs of congestion. Pedunculated lipomas in the mesentery of horses causing intestinal volvulus and obstruction are a frequent cause of small-intestine strangulation in aged horses. To the authors' knowledge, intramural intestinal lipomas to date have not been described in the horse. The mare recovered without complications and was free of colic symptoms after 6 months.

Infiltrative lipoma causing vertebral deformation and spinal cord compression in a dog.

A 4-year-old, male Bernese mountain dog was evaluated for a 1-year history of right hemiparesis. Computed tomography revealed a large hypoattenuating mass severely deforming the C5 vertebral arch, invading the C6 spinal canal, and causing spinal cord compression. The signal characteristics of magnetic resonance imaging indicated a lesion composed of adipose tissue. The mass was removed via right hemilaminectomy, and histopathological examination confirmed it was an infiltrative lipoma. The compressive lesion remained unresolved, so the dog underwent a second operation, after which he regained some ambulatory function. Although postoperative adjunctive radiation therapy was performed, the dog died 201 days after the first operation.

Intraluminal tracheal lipoma as a rare cause of dyspnoea in a dog.

BACKGROUND: Tracheal tumors are rarely diagnosed in veterinary medicine and the majority of tracheal neoplasia reported in adult dogs are malignant. Intratracheal lipoma has not been previously reported in the veterinary literature. CASE PRESENTATION: A 7-year-old Briard dog was evaluated for inspiratory dyspnoea and an inspiratory wheeze. Cervical radiographs and tracheoscopic examination revealed an intratracheal mass that was surgically removed. The dog has been asymptomatic after the surgery. CONCLUSIONS: Based on histopathology, the mass was diagnosed as lipoma. To the authors' knowledge, this is the first published report of an intratracheal lipoma in the veterinary literature.