Diagnostic imaging features of hepatic myelolipoma incarcerated in a peritoneopericardial diaphragmatic hernia in a cat.

A 1-year-old male Persian cat was presented for castration. Liver incarcerated in a peritoneopericardial diaphragmatic hernia (PPDH) was diagnosed through pre-anesthetic tests. Multiple homogeneous hyperechoic nodules in the hepatic parenchyma were identified using ultrasound. The nodules showed decreased attenuation compared with normal hepatic parenchyma, and the herniated hepatic parenchyma showed increased arterial and decreased portal enhancement on computed tomography. From the histopathology, we diagnosed hydropic degeneration with portal fibrosis and myelolipoma. This report presents diagnostic imaging features of hepatic myelolipoma incarcerated in a PPDH in a cat. When perfusion of the hepatic parenchyma is altered, surgical treatment should be considered.

Epidural myelolipoma in a Silken Windhound.

A 12-year-old female spayed, Silken Windhound dog was presented with a 3-month history of lethargy and cervical and lumbosacral spinal pain. No significant abnormalities were noted on CBC or serum biochemical assays. Magnetic resonance imaging of the spine demonstrated a soft tissue mass within the ventral and right epidural space at the level of the L7 vertebra. During surgery, a pale brown mass was identified within the epidural fat. Cytologic and histopathologic examinations demonstrated that the mass was composed of adipose tissue and hematopoietic elements, consistent with a myelolipoma. The lumbosacral spinal pain resolved after surgery. Epidural myelolipomas are rarely reported in the human and veterinary literature.

Nontraumatic hemoabdomen and pancytopenia secondary to myelolipoma in a cat.

OBJECTIVE: (1) To report an unusual etiology for nontraumatic hemoabdomen in cats, and (2) to describe onset and recovery from severe, unexpected pancytopenia seen after surgical removal of a large intra-abdominal myelolipoma. CASE SUMMARY: A 14-year-old neutered male domestic shorthair cat was presented for emergent treatment of suspected nontraumatic hemoabdomen. A hyperechoic mass, with ultrasonographic echogenicity similar to fat, was found in the right cranial abdomen and believed to be associated with the mesentery. Cytological examination of abdominal fluid identified marked extramedullary hematopoiesis within the hemorrhagic effusion. Exploratory laparotomy identified a hepatic mass, which was resected, and revealed to be a hepatic myelolipoma on histopathological examination. The patient's initial recovery was uneventful. However, continued hyporexia resulted in readmission 4 days postoperatively, at which time the patient was found to have a profound, tri-lineage pancytopenia, and cytological evidence indicative of bone marrow recovery. The pancytopenia resolved with continued medical management and supportive care. NEW OR UNIQUE INFORMATION PROVIDED: Ruptured myelolipoma is not a commonly considered differential for nontraumatic hemoabdomen in cats. Furthermore, severe pancytopenia is unexpected following surgical resection of a myelolipoma. This case provides a unique clinical presentation of both nontraumatic hemoabdomen and bone marrow recovery.

Removal of a Tracheal Myelolipoma in a Cockatiel (Nymphicus hollandicus) by Surgical Resection and Anastomosis.

A 17-year-old, female cockatiel (Nymphicus hollandicus) was presented for a 1-week history of respiratory distress. The clinical signs were consistent with tracheal obstruction; therefore, an air sac cannula was placed to reduce respiratory compromise. Radiographic images of the patient revealed a round, intraluminal, soft tissue opacity in the trachea. The obstruction could be visualized via transtracheal illumination, but tracheoscopy was not feasible because of the size of the patient. Attempts to manually extirpate the obstruction were unsuccessful, and the trachea subsequently avulsed in the midcervical region. Tracheal resection and anastomosis was performed, and the obstruction was removed with the associated tracheal ring. The patient recovered uneventfully and was doing well at follow-up evaluations at 9 days, 24 days, and 10 months after the surgical procedure. The histologic diagnosis was ossifying myelolipoma arising from bone marrow within the tracheal ring.

[Multiple choristoma and a myelolipoma in a Sheltie]. / Multiple Choristome und ein Myelolipom bei einem Sheltie.

An 11-year-old female Sheltie was presented with inappetence and a progressive increase in abdominal distention. Abdominal ultrasound revealed a large cystic mass in the midabdomen and cystic lesions in the right liver lobe and in the caudal pole of the left kidney. Histopathologic examination of the resected tissue revealed a myelolipoma of the spleen, dispersed splenic tissue in the liver and dispersed uterine and salpinx tissues in the kidney. This report describes the clinical, ultrasonographic and computed tomographic features and the results of histopathology. In addition to the abnormally large and cystic myelolipoma of the spleen, the great number of choristomas is remarkable, which has not previously been documented in a dog.

Hepatic lipomas and myelolipomas in subsistence-harvested bowhead whales Balaena mysticetus, Alaska (USA): a case review 1980-2016.

We describe a case series of benign hepatic fatty tumors in 10 subsistence-harvested bowhead whales. Microscopic features included lipomatous and myelolipomatous masses. Extensive atrophy and/or destruction of hepatic parenchyma was not observed. No other significant disease was present except in an animal with unrelated chronic pleuritis. Based on our longitudinal case series (1980-2016) which identified 1-2 hepatic lipomas and myelolipomas in landed whales annually at Barrow, Alaska (USA), since 2012, hepatic lipomas and myelolipomas are occasionally seen in hunter-harvested bowhead whales. A conservative estimate for the percentage of bowhead whales with hepatic fatty tumors in landed whales in Barrow from 2012 to 2016 was 6% (7/111). The pathogenesis and exact cell origin of these benign fatty tumors in bowhead whales is undetermined. Assessment of further cases is warranted to better define the tissue distribution and pathogenesis of these tumors in bowhead whale liver.

Hepatic myelolipoma in two Goeldi's monkeys from South America held captive.

Two cases of hepatic myelolipoma in Goeldi's monkeys from South America are described. One was a female evaluated due progressive abdominal distension. Ultrasound and computed tomography detected hepatic mass. Partial hepatectomy was performed, but the monkey died after surgery. Case 2 was a male that died suddenly, showing non-specific clinical signs.

RETROSPECTIVE REVIEW OF THE PREVALENCE OF MYELOLIPOMA IN GOELDI'S MONKEYS (CALLIMICO GOELDII).

Myelolipomas are mesenchymal tumors composed of adipose and hematopoietic tissue. They have been reported in many species, including domestic dogs and cats, birds, mustelids, wild felids, and nonhuman primates. Myelolipomas in Callitrichidae have been reported at postmortem examination and rarely antemortem. Multiple cases of hepatic myelolipomas associated with morbidity in Chicago Zoological Society's collection of Goeldi's monkeys (Callimico goeldii) prompted a global retrospective study to determine the prevalence and investigate factors associated with this condition. A total of 842 postmortem examination reports (1965-2013) collected from 133 captive collections were reviewed. Myelolipomas were reported in 17.2% (n=145) of animals, with significantly more female cases than male (P=0.023). There was a significantly older mean age at death in affected animals (134 months) compared to unaffected animals (79 months) (P<0.0001). Myelolipomas were diagnosed in the liver in all affected animals, and rarely in the adrenal or spleen. One in five (22.1%) affected Callimico had notable morbidity associated with this disease, which is markedly different from the primarily benign reports in other species. To identify disease, prevent morbidity from hepatic myelolipoma, and improve care of Callimico species in zoological collections, new Species Survival Plan (SSP) medical management recommendations include incorporating abdominal ultrasonographic examination during routine physical examinations in addition to previously recommended hematological and serum biochemical evaluations. Future studies are merited to examine the prevalence, risk factors, health effects, and treatment options of myelolipoma in living collections.

Intraocular myelolipoma in a dog.

An 8-year-old Scottish terrier was presented with a red and painful right eye. Slitlamp biomicroscopy and ocular ultrasound demonstrated the presence of a large mass in the anterior chamber. Enucleation was performed one week after initial presentation. Histological examination of the eye revealed a relatively well-delineated mass distorting the dorsal iris and occupying most of the anterior chamber. The tumor was composed of fully differentiated adipose tissue and normal hematopoietic cells of the three major blood-forming elements. These findings were most consistent with the diagnosis of an anterior chamber myelolipoma distorting the iris. To the author's knowledge, this is the first report of an intraocular myelolipoma in any species.

Epidural myelolipoma in a Husky-cross: a case report.

Epidural spinal myelolipoma was diagnosed in an 11.5-year-old castrated male Husky-cross that was evaluated at the veterinary teaching hospital due to progressive thoracolumbar spinal hyperaesthesia and mild proprioceptive pelvic limb ataxia. A focal, ill-defined mildly inhomogenous extradural mass lesion was detected by MRI. The dog was euthanized. At necropsy an extradurally located reddish mass of about 2.5 cm in diameter was present in the vertebral canal. The mass was identified histopathologically as an epidural myelolipoma.

Hepatic multiple myelolipoma with severe coelomic edema in a red-bellied tamarin (Saguinus labiatus).

This report describes hepatic multiple myelolipoma with severe coelomic edema in a 14-year-old, male red-bellied tamarin (Saguinus labiatus). Multiple small and large nodules were formed in all lobes of the liver. Histopathologically, the nodules comprised mature and normal adipocytes and hematopoietic elements at various ratios that were composed of granulocytic, erythrocytic, and megakaryocytic series in various phases of maturation. All nodules were encapsulated and demarcated hepatocytes around masses. Myelolipoma in the liver is rare, and there are no reports of any cases to date. To our knowledge, this is the first report of hepatic multiple myelolipoma in a red-bellied tamarin.

Adrenalectomy in dogs with adrenal gland tumors: 52 cases (2002-2008).

OBJECTIVE: To evaluate predictors of survival time in dogs undergoing adrenalectomy and identify risk factors associated with adrenal gland tumor metastasis and vein thrombosis. DESIGN: Retrospective case series. ANIMALS: 52 dogs with primary adrenal gland tumors. PROCEDURES: Medical records were reviewed. Signalment, tumor features, and information from surgical procedures were evaluated to identify factors predictive of overall survival time, which was defined as the time from surgery until death. The association between metastasis or vein thrombosis and tumor type, size, and site (right or left adrenal gland) was investigated. RESULTS: On the basis of results of univariate analysis, survival time was significantly shorter for dogs with adenocarcinoma, tumor major axis length ≥ 5 cm, metastasis, and vein thrombosis and when adrenalectomy was combined with an additional abdominal surgical intervention. On multivariate analysis, survival time was significantly shorter for dogs with an adrenal gland tumor with major axis length ≥ 5 cm and for dogs with metastasis or vein thrombosis. Significant associations were found between metastasis and adenocarcinoma and between vein thrombosis and tumors with major axis length ≥ 5 cm. CONCLUSIONS AND CLINICAL RELEVANCE: Dogs with an adrenal gland tumor with major axis length ≥ 5 cm, documented metastasis, or vein thrombosis had a poorer prognosis. Metastasis was more frequent in dogs with adenocarcinoma and vein thrombosis when tumors were ≥ 5 cm in length.

Hepatic Myelolipoma with systemic amyloidosis in a goose (Anser cygnoides domesticus).

We report here a case of hepatic myelolipoma with systemic amyloidosis in a goose (Anser cygnoides domesticus), which died suddenly following the short history of weakness and greenish diarrhea. At necropsy, multiple yellowish-white foci were observed on the surface of the prominently enlarged liver. Histologically, there were multiple foci of adipose tissue admixed with myeloid elements in various proportions in the liver as well as amyloid deposition in several organs including the liver, intestine, spleen, kidney, and ovary. Ultrastructurally, erythroblast-like cells and myelocytes, which showed various stages of differentiation, were observed in the foci of the liver. These findings shared characteristics of hepatic myelolipoma which is very rare in birds.

Hepatic myelolipoma incarcerated in a peritoneopericardial diaphragmatic hernia in a cat.

Hepatic myelolipoma incarcerated in a peritoneopericardial diaphragmatic hernia was diagnosed in an 11-year-old, desexed female Persian cat. The cat was initially referred for investigation of tachypnoea and dyspnoea. Peritoneopericardial diaphragmatic hernia is a common incidental finding in cats and is usually asymptomatic. Myelolipoma is an extremely rare benign tumour, composed of extramedullary haematopoietic cells and adipose tissue. Myelolipomas are hypothesised to result from metaplastic alteration, rather than a neoplastic process, although this theory cannot be substantiated. The present case is only the fourth report of such an unusual occurrence in cats and displays significant differences to previous reports. Hepatic entrapment and burgeoning of the mass within the pericardial sac resulted in cardiac tamponade and overt signs of right-sided cardiac failure. Surgical intervention was successful and despite concerns regarding the cat's clinical presentation and the gross appearance of the lesion(s), a good long-term outcome is anticipated.

Hepatic myelolipoma and amyloidosis with osseous metaplasia in a swan goose (Anser cygnoides).

An adult swan goose (Anser cygnoides) kept in a zoological garden had gross hepatic enlargement with extensive ill-defined white foci. Microscopically, the hepatic lesions were composed of a mixture of adipocytes and myeloid cells. The goose was also affected with systemic amyloidosis and there were areas of osseous metaplasia associated with deposition of amyloid within the liver.

Multicentric myelolipoma in a dog.

We report herein a case of multicentric myelolipoma in an 11-year-old beagle dog that presented with vomiting. Laparotomy demonstrated the presence of a large mass adherent to the greater omentum and multiple small white maculae in the spleen. Cytological and histological examinations revealed that the mass and maculae comprised mature adipocytes and hematopoietic elements including granulocytic, erythrocytic and megakaryocytic series in several phases of maturation and macrophages containing hemosiderin deposits, resembling bone marrow. Multicentric myelolipoma was diagnosed. This is first report of multicentric myelolipoma in a dog.

Imaging diagnosis--bilateral adrenal adenomas and myelolipomas in a dog.

A 10-year-old neutered female Pug was evaluated for a left adrenal mass detected previously by ultrasonography. Using computed tomography, a fat-attenuating, rim-enhancing left adrenal mass and a homogeneous, soft-tissue attenuating, intensely enhancing right adrenal mass were found. A left adrenalectomy and right adrenal biopsy were performed and the final diagnosis was bilateral adrenal adenomas and myelolipomas. Myelolipomas are rare, benign, endocrinologically inactive tumors composed of well-differentiated adipose tissue and a variable amount of hematopoietic cells of both lymphatic and myeloid lineages, which may account for the different appearance on tomographic images.

Epidural spinal myelolipoma in a dog.

Epidural spinal myelolipoma was diagnosed in a 13-year-old, male Siberian husky that was referred for evaluation of progressive pelvic limb paresis and urinary incontinence. An epidural mass was detected by magnetic resonance imaging and computed tomography. The mass was removed and identified histopathologically as an epidural myelolipoma. Pelvic limb paresis improved after surgery, but urinary retention associated with neurological bladder dysfunction persisted.