Intraosseous hibernoma: clinicopathologic and imaging analysis of 18 cases. Intraosseous hibernomas are rarely reported tumours with brown adipocytic differentiation of unknown aetiology, with only 38 cases documented in the literature. We sought to further characterise the clinicopathologic, imaging and molecular features of these tumours. Eighteen cases were identified occurring in eight ). Chromosomal microarray analysis, performed on four cases, did not show clinically significant copy number variation across the genome or on 11q, the site of AIP and MEN1. Analysis of 18 cases of intraosseous hibernoma, to our knowledge, the largest series to date, revealed that these tumours are most often detected in the spine and pelvis of older adults. Tumours were generally small, sclerotic
Liposarcoma With Hibernoma-like Histology: A Clinicopathologic Study of 16 Cases. Hibernoma is an uncommon benign tumor of brown fat cells that consistently expresses uncoupling protein 1 (UCP1). Herein, we clinicopathologically characterized 16 liposarcomas, for which histology, at least focally, closely resembled that of hibernoma, including sheets of brown fat-like, finely multivacuolated -to-eosinophilic tumor cells with no or minimal nuclear atypia. The cohort consisted of 4 well-differentiated liposarcomas (WDLSs), 6 dedifferentiated liposarcomas with a concomitant WDLS component, and 6 myxoid liposarcomas (MLSs). For all dedifferentiated liposarcoma cases, hibernoma-like histology was present only in the WDLS component. All tumors presented as large, deep-seated masses. Hibernoma-like
Hibernoma Mimicking Atypical Lipomatous Tumor: 64 Cases of a Morphologically Distinct Subset. Hibernoma is a benign adipocytic tumor with predilection for subcutaneous tissue of the thigh, upper trunk, and neck of middle-aged adults. 11q13 rearrangement resulting in MEN1/AIP codeletion is characteristic. Hibernomas are composed, in varying proportions, of brown fat cells, mature adipocytes , and microvacuolated lipoblast-like cells. Examples containing predominantly multivacuolated lipoblast-like cells are uncommon and distinction from atypical lipomatous tumor (ALT) is important for clinical management. We herein present the clinicopathologic features of 64 hibernomas histologically mimicking ALT. MDM2 and CDK4 immunohistochemistry as well as MDM2 fluorescence in situ hybridization were performed
Gastric hibernoma: a novel location and presentation of a rare tumor We present a case of gastric hibernoma, an unusual tumor with a location novel to the literature. A 39-year-old female presented with one year of upper gastrointestinal bleeding and dysphagia. Gastroenterology performed an esophagogastroduodenoscopy with ultrasound and identified a 6 cm mass within the muscularis propria of the antrum. Computed tomography demonstrated a 9.7 × 7.8 × 4.8 cm heterogeneous antral mass with internal septa. A distal gastrectomy with Bilroth I gastroduodenostomy was performed with 4 cm proximal and 2 cm distal margins. Excision was appropriate to make the diagnosis, exclude malignancy, and remove a symptomatic mass. Hibernoma was confirmed by histopathology. These are rare tumors of brown fat named
Clinical, Radiological, and Pathological Features of Intraosseous Hibernoma: a systematic review of case reports and case series PROSPERO International prospective register of systematic reviews Print | PDF PROSPERO This information has been provided by the named contact for this review. CRD has accepted this information in good faith and registered the review in PROSPERO. The registrant confirms
Paraspinal hibernoma: Grand Round presentation of a rare benign adipocytic tumor. We report an uncommon case of paraspinal hibernoma with a T12-L1 foraminal extension and discuss the potential differential diagnoses of paraspinal adipocytic tumors. A 32-year-old woman consulted our department with a right subscapular and paraspinal mass. There was no associated neurological deficit. The MRI revealed a paraspinal adipocytic tumor with a T12-L1 right foraminal extension. Percutaneous biopsy suggested a diagnosis of hibernoma. Hibernoma is a rare and benign adipocytic tumor arising from embryologic remnants of brown fat. Specific MRI findings are discussed to differentiate hibernoma from other soft-tissue tumors. A planned marginal resection was undertaken with the final histopathology
Hibernoma in the clavicular fossa: A case report and literature review A hibernoma is a benign soft tissue tumor consisting of brown adipose tissue. The tumors are mostly located in the thigh, back, and shoulder region. They are rarely found in the supraclavicular fossa. We report a 39-year-old woman who presented with a painless, slow-growing mass on the left supraclavicular fossa for nearly 15
Intraosseous Hibernoma: A Rare and Unique Intraosseous Lesion Hibernoma is a rare benign tumor of adults that is composed of multivacuolated adipocytes resembling brown fat cells. Hibernoma typically occurs in soft tissue, and intraosseous examples are very rare. Intraosseous hibernomas can radiologically mimic metastatic carcinoma and other tumorous conditions. To collect the intraosseous hibernomas, we searched the pathologic database and reviewed the hematoxylin and eosin (H&E)-stained slides of bone biopsy samples performed to differentiate radiologically abnormal bone lesions from 2006 to 2016. A total of six intraosseous hibernoma cases were collected, and clinical and radiological information was verified from electronic medical records. H&E slide review and immunohistochemical
Intramuscular Hibernoma of the Scapular Region Misdiagnosed on Cytology as a Malignant Lesion: A Report of a Rare Case Hibernomas are extremely rare benign tumors of adipose tissue characterized by an admixture of brown fat cells with granular, multivacuolated cytoplasm and white fat cells. Hibernomas account for 1.6% of benign adipose tissue tumors and approximately 1.1% of all adipocytic tumors . Around 10% of these cases are intramuscular. It was initially described in the early 1900s as being composed of brown fat. Hibernomas usually occur in third to fourth decades of life and the most frequent sites being thigh, trunk, shoulder, back etc. Cytological differential diagnoses of hibernoma include well differentiated liposarcoma, myxoid/round cell liposarcoma, chondroid lipoma and benign
A Twenty-Four-Year-Old Woman with Left Flank Lipoma-Like Hibernoma A 24-year-old woman presented with a 5-month history of a left flank mass that was painful on palpation. Magnetic resonance imaging revealed a 10.0 × 6.0 × 2.5 cm mass consistent with lipoma. A fatty lobulated mass was excised and subjected to H&E staining and immunohistochemical analyses. The specimen consisted of mature univacuolated adipocytic cells, with intermixed multivacuolated eosinophilic granular cells. No atypia or hyperchromasia was identified. Most of the cells were S100 positive and Ki-67 immunonegative. A diagnosis of a lipoma-like hibernoma was rendered. Hibernomas are rare benign lipomatous tumors that show differentiation toward brown fat. The lipoma-like hibernoma subtype is rare and can be misdiagnosed
Extra peritoneal giant pelvic hibernoma: a case report Abdominal hibernoma is a rare slow-growing tumor originating from brown adipose tissue. Due to its rarity, only a few case reports have been published so far. Pelvic localization is anedoctal and preoperative differential diagnosis with other malignancies may be challenging. We present the case of a woman who, due to a lower abdominal pain , underwent an abdominal ultrasonography with diagnosis of a 15 cm hyperechogenous pelvic mass. A subsequent MRI showed a 16 × 5.8 × 7.8 cm lesion anterior to the left iliacus muscle, with an intra- and extrapelvic component longitudinally extending from the left anterior superior iliac spine until the lesser trochanter. Surgical resection was performed and final histopathology was consistent with hibernoma
A Rare Case of Hibernoma Occasionally Identified by 18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in a Patient with Lung Cancer Hibernoma is a benign tumor arising from brown fat tissue. Conventional imaging techniques are not able to differentiate it from other benign lesions or malignant fatty tumors. We report the case of a 73-year-old patient who underwent a thorax to be a hibernoma. This case shows that hibernoma can appear as a malignant-like lesion on 18F-FDG-PET/CT scan as per other imaging techniques, and the grade of FDG uptake does not accurately reflect malignancy in this fat-containing tumor. However, 18F-FDG-PET/CT with its whole-body scanning capability may represent a useful imaging tool in identifying, in the course of an imaging study for oncological
Hibernoma Showing High Uniform Accumulation on an 18F-Fluorodeoxyglucose Positron Emission Tomography Scan: A Case Report Hibernoma is a rare, benign, soft tissue tumor arising from brown fat that cannot be distinguished from other lipogenic tumors on computed tomography and magnetic resonance imaging (MRI) scans. On the other hand, the image of hibernoma on F-fluorodeoxyglucose positron emission tomography (F-FDG-PET) is different from that of other lipogenic tumors. However, fewer studies have investigated the typical features of hibernoma on PET scans. We present the case of a hibernoma that was incidentally detected on F-FDG-PET. A 48-year-old Asian man underwent F-FDG-PET for routine follow-up of gastric cancer. The patient reported a painless soft mass on the upper arm that had
Mediastinal Hibernoma: A Rare Case with Radiologic-Pathologic Correlation Hibernomas, especially located in the mediastinum, are extremely rare benign tumors, which are important to consider in the differential diagnosis of a heterogeneously enhancing mass with areas of fat attenuation on imaging of an often incidentally discovered mass. Other common possibilities in the differential include malignant tumors, such as liposarcoma, hence histopathology is usually required to confirm the diagnosis. Hibernomas often follow the distribution of sites of persistence of brown fat in adults, and intrathoracic locations are unusual. We present a very rare case of a mediastinal hibernoma in a 53-year-old woman. She presented to the emergency department with severe, progressive right neck and shoulder
Hibernoma: diagnostic and surgical considerations of a rare benign tumour Hibernoma is a rare, benign tumour of brown fat origin. Less than 250 cases have been reported in the literature. We present a case of a 19-year-old man referred to surgical oncology for evaluation of a large soft tissue mass near the apex of his right scapula. Complete surgical excision was performed, sparing the overlying latissimus dorsi musculature. Surgical pathology revealed findings were consistent with hibernoma, grossly showing a well-encapsulated fluctuant mass measuring 21.4×14.4×5.3 cm, and histologically composed of brown fat adipocytes. The mainstay of treatment is surgical excision of the mass. Primary goals of the operation include complete removal of the mass to prevent recurrence and sparing of adjacent
An unusual presentation of a rare benign tumor in the head and neck: A review of hibernomas. Hibernomas are rare benign tumors that may present in the head and neck in an unusual manner similar to more common malignant tumors such as lymphoma. Our case report describes several characteristics of a patient and benign tumor presentation that is atypical for the usual presentation of hibernomas as reviewed in the literature. Although hibernomas are rare, our report and review of the literature highlights a particular patient population and important key findings that should make one consider these benign tumors in the differential diagnosis of a young patient presenting with a neck mass.
Intra-osseous Hibernoma: a case report and review of the literature. A case report and a literature review are presented. To describe and review the clinical presentation and characteristic imaging and pathology findings of intraosseous hibernoma. Hibernomas are lesions of brown fat. Brown fat is typically found in newborn mammals and is rich in mitochondria, thus enabling its role in thermoregulation. It represents a small proportion of adult fat and is distinct from the more common "white fat." Rarely does a hibernoma occur within bone. To the authors' knowledge, 5 cases in all have been reported in the literature. We report the first case to our knowledge of an intraosseous hibernoma occurring within the lumbar spine as well as a review of the literature. Characteristic findings from
Hibernoma – two patients with a rare lipoid soft-tissue tumour Hibernomas are rare benign soft-tissue tumours arising from brown fat tissue. Although imaging characteristics are not specific certain imaging features, common locations and patient demographics may suggest hibernoma as a differential diagnosis. We report on two 48-year-old male patients with hibernoma. The tumour presented , respectively. Complete surgical resection confirmed the diagnosis of hibernoma thereafter. In soft tissue tumours with fatty components hibernoma may be included into the differential diagnosis. Because of the risk of sampling errors in hibernoma-like tissue components of myxoid and well-differentiated liposarcoma, complete resection is mandatory. This article also reviews the current imaging literature
The Values and Limitations of FDG-PET/CT for Diagnosis of HibernomaHibernoma is a rare benign lipogenic tumor of brown fat that develops in a wide variety of locations. Although the features of hibernoma demonstrated by MRI resemble those of liposarcoma, recent FDG-PET/CT studies have documented higher radiotracer uptake than liposarcoma, suggesting that FDG/PET/CT is useful for differentiating hibernoma from liposarcoma. Here we report two cases of hibernoma that showed relatively lower SUVs than those reported previously, lying within the range for liposarcoma. Our findings emphasize that hibernoma needs to be included in the differential diagnosis of any fat-containing tumor showing intense accumulation by FDG-PET/CT. Although it is unlikely that such a rare condition could be reasonably