Edit concept Question Editor Create issue ticket

Hibernoma

Hibernomas

Hibernoma is an infrequent type of benign soft tissue tumor composed of brown adipocytes that may present in a similar manner to liposarcoma, despite the fact that it has no malignant or metastatic potential.


Presentation

Hibernomas are usually located in the interscapular region, but may also be encountered in the cervical, thigh or axillary areas. Intra thoracic, intramuscular, abdominal and retroperitoneal lesions have also been described, as well as exceptional locations such as the uterus, breast, popliteal area, cranium, pericardium [1] or mediastinum. Lesions may be multiple or bilateral, are painless, but may cause symptoms related to their mass effect [2] or to their secretory activity, as they are known to sometimes produce steroid hormones. They are usually described as slow growing (but fast growth is also possible) and firm or rubbery and are mostly encountered in adults in their thirties, and differential diagnosis with lipomas and liposarcomas must be taken into consideration, given that clinical presentations of the three pathological entities often overlap [3] [4]. Once the diagnosis of hibernoma is established, the physician does not need to be concerned about malignant transformation or metastasis [5]. However, recurrence is possible, although very rare.

Fishing
  • FISH studies revealed large heterozygous deletions within the 11q13 band, from 11q13.1 to 11q13.5.[ncbi.nlm.nih.gov]
  • This alteration can be detected by metaphase fluorescent in situ hybridization (FISH). MEN1 gene (11q13.1) is most frequently deleted, while GARP gene (11q13.5) may also be involved.[en.wikipedia.org]
  • FISH MDM2 amplification testing was negative, ruling out well differentiated liposarcoma. Given this unusual histology and location, a second opinion was obtained and the unusual diagnosis of a hibernoma was confirmed.[academic.oup.com]
Limited Mobility
  • The physical examination was unremarkable except for large swelling of the left side of the neck (Panel A), which caused limited mobility of the neck. The neck mass was firm, mobile, and nontender.[nejm.org]
Soft Tissue Swelling
  • Radiographs of patients with lipoma arborescens reveal soft-tissue swelling around the joint that may or may not be radiolucent. Sonography is useful for documenting the joint effusion as well as the villous nature of the mass.[pubs.rsna.org]
Aspiration
  • Two middle-aged men diagnosed clinically as having lipomas were subjected to fine needle aspiration (FNA). Smears revealed typical hibernoma cells with a minor percentage of eosinophilic cells and mature adipocytes.[ncbi.nlm.nih.gov]
Hoarseness
  • A case of a 52-year-old female who was admitted with a slowly worsening hoarseness is presented. Further investigation revealed a left upper mediastinal mass next to the aortic arch. Upon surgical exploration a soft encapsulated mass was identified.[ncbi.nlm.nih.gov]
Left Flank Pain
  • A 51-year-old woman presenting with recurrent left flank pain was diagnosed with left kidney stone. Abdomen ultrasound and i.v. pyelografy showed pyelic stone of 2 cm without other pathologies of the urinary tract.[ncbi.nlm.nih.gov]
Chest Pain
  • In this report, we describe a 42-year-old man with no past medical history and right chest pain. Imaging studies showed an osteolytic lesion with fat attenuation lesion in the right fourth rib.[ncbi.nlm.nih.gov]
  • Our patient presented right chest pain without fever or weight loss. Hibernomas have CT and MRI appearances similar to other benign and malignant fibrous and lipomatous tumours [13].[latunisiemedicale.com]
  • The lump was slowly increasing in size, but not associated with backache, shoulder movement restriction, cough, chest pain or dyspnea. There was no history of any other swelling in the body, any chronic medical illness or any prior surgery.[ijp.iranpath.org]
Night Sweats
  • We present an unusual case of supraclavicular benign hibernoma in a 12-year-old girl who presented with chest discomfort, night sweats, shortness of breath, fatigue, and pruritus.[ncbi.nlm.nih.gov]
  • Lymphoma – Patients often present with systemic symptoms (fever, night sweats, weight loss, etc) in addition to a growing mass. Rhabdomyoma – Benign tumor of striated muscle that occurs in children and adults.[visualdx.com]
  • She reported no trauma to the area and exhibited no systemic signs of weight loss, fatigue, fever, chills, or night sweats. Physical examination revealed a soft nontender right medial thigh mass measuring 18 20 cm.[journals.lww.com]
  • CASE REPORT A 42-year-old man with no past medical history, was admitted for a 6-month history of a right chest pain without fever, chills, night sweats or weight loss. Physical examination was normal.[latunisiemedicale.com]
Pruritus
  • We present an unusual case of supraclavicular benign hibernoma in a 12-year-old girl who presented with chest discomfort, night sweats, shortness of breath, fatigue, and pruritus.[ncbi.nlm.nih.gov]
Back Pain
  • We describe the imaging and pathological features of a rare case of sacral hibernoma that was discovered incidentally in a patient with low back pain. The benign-appearing, small intraosseous lesion in the sacrum was sclerotic on CT.[ncbi.nlm.nih.gov]
  • Case report Section: In a work-up of a 40-year-old female with a history of low back pain, a routine MRI of the lumbar spine identified an incidental lesion.[doi.org]
  • Imaging Findings A 43-year-old female patient presented to our department with low back pain which did not respond to painkillers and ambulation difficulties.[eurorad.org]
Hip Pain
  • In this report, we describe a 50-year-old woman with a history of stage IIB breast cancer and posterolateral right hip pain.[ncbi.nlm.nih.gov]
  • Liposclerosing myxofibrous tumor of the intertrochanteric femur in a 39-year-old man with mild hip pain.[pubs.rsna.org]
Low Back Pain
  • We describe the imaging and pathological features of a rare case of sacral hibernoma that was discovered incidentally in a patient with low back pain. The benign-appearing, small intraosseous lesion in the sacrum was sclerotic on CT.[ncbi.nlm.nih.gov]
  • Imaging Findings A 43-year-old female patient presented to our department with low back pain which did not respond to painkillers and ambulation difficulties.[eurorad.org]
  • Case report Section: In a work-up of a 40-year-old female with a history of low back pain, a routine MRI of the lumbar spine identified an incidental lesion.[doi.org]
Suggestibility
  • Radioimaging was suggestive of a mass in both parapharyngeal spaces; the lesion was more prominent on the left side. The mass extended from C2 into the retropharyngeal space and superior mediastinum.[ncbi.nlm.nih.gov]
Aggressive Behavior
  • Hibernomas are universally benign and are not known to recur or have an aggressive behavior, even in incompletely excised lesions.[ncbi.nlm.nih.gov]
Neck Swelling
  • An unusual case of congenital benign hibernoma, in the submandibular region, in a 2.5 years old girl, is reported, who presented with a progressively increasing neck swelling. A CAT scan of neck revealed a superficial and deep low density mass.[ncbi.nlm.nih.gov]
Flank Pain
  • A 51-year-old woman presenting with recurrent left flank pain was diagnosed with left kidney stone. Abdomen ultrasound and i.v. pyelografy showed pyelic stone of 2 cm without other pathologies of the urinary tract.[ncbi.nlm.nih.gov]

Workup

The first step in diagnosing a hibernoma after the clinical suspicion is raised is to perform imaging procedures. A radiography of the affected region will show no bone erosion or calcification. Echography describes hyperechoic tissue, while Doppler imaging highlights the presence of enlarged vessels. Computer tomography scanning describes well vascularized, well circumscribed, heterogeneous, diffusely septated lesions with a possibly incomplete peripheral capsule. Hibernoma signal intensity in magnetic resonance imaging is variable [6], usually high, but slightly inferior to that of subcutaneous tissue [5]. The degree of homogeneity is variable [7]. This method shows diffuse gadolinium enhancement of an otherwise isointense or mildly hypointense tissue formation. Myxoid hibernomas, being richer in water have higher signal intensity on magnetic resonance imaging scans [8]. Fluorodeoxyglucose positron emission tomography shows important radiotracer capture [9] due to the fact that hibernomas contain numerous mitochondria and are metabolically very active. Scintigraphy also reveals high radiotracer uptake with 99mTc-tetrofosmin, 123I-meta-iodobenzylguanidine and 99mTc-methoxyisobutylisonitrile administration. If an angiography is considered to be necessary, it may reveal, besides intense vascularization, the presence of internal arterio-venous shunting [10] which is important information prior to excision.

If clinical and imaging differential diagnosis cannot exclude a malignancy, excision is imperative. Analysis of the surgical specimen reveals a light brown to gray mass of tissue surrounded by a thin capsule [11]. Microscopic examination reveals high -number of mature, multivacuolated or uni vacuolar adipocytes intersecting with brown fat, intense vascularization, and few adipocyte atypia. Tumors may, however, be more or less well differentiated. Immunohistochemical analysis shows a positive cluster of differentiation (CD) 68 and negative CD 34.

In cases where cytogenic analysis reveals the presence of a 11q13 translocation, liposarcoma is improbable [12]. Rearrangements in the 11q13-21 region can be detected using metaphase fluorescent in situ hybridization.

Mediastinal Mass
  • Further investigation revealed a left upper mediastinal mass next to the aortic arch. Upon surgical exploration a soft encapsulated mass was identified. Pathology was consistent with hibernoma.[ncbi.nlm.nih.gov]

Treatment

  • The literature provides only a few treatment details regarding this variant.[ncbi.nlm.nih.gov]

Prognosis

  • This review discusses the clinical features, radiologic and histopathologic characteristics, ancillary studies, suggested pathogenesis, differential diagnosis, and treatment of and prognosis for these uncommon lesions.[ncbi.nlm.nih.gov]
  • There are multivacuolated cells and a cell with a central nucleus IMMUNOHISTOCHEMISTRY Positive • S100 • Oil red O • Sudan black Negative • CD 34 • P53 PROGNOSIS BIOLOGICAL BEHAVIOR • Hibernoma is benign and does not metastasize or convert to a malignancy[tumorsurgery.org]
  • Nuclear medicine FDG-PET: FDG avid, although practically this has not been shown to help differentiate from malignancy Treatment and prognosis The treatment of hibernomas consists of complete surgical excision.[radiopaedia.org]

Etiology

  • He subsequently underwent dual time point FDG PET/CT imaging which revealed a significant rise in standard uptake value (SUV) within the lesion over time, favoring a malignant etiology.[ncbi.nlm.nih.gov]
  • Etiology The etiology involves clinically significant persistence of remnants of or accumulation of brown fat in regions where small amounts of brown fat normally persist as vestigial remnants.[dermatologyadvisor.com]

Epidemiology

  • Usually asymptomatic. [3] Epidemiology: Young adults. Gross Well-circumscribed. Lobulated and light-brown on sectioning.[librepathology.org]
  • Epidemiology [ edit ] The tumor is rare, affecting adults in the 4th decade most commonly. Patients are usually younger than those who present with a lipoma. There is a slight male predominance.[en.wikipedia.org]
  • Definition / general Lipoma containing prominent brown adipocytes that resembles normal brown fat as classic lipoma resembles white fat Epidemiology Rare (2% of lipomas) Mean age 26 - 38 years; 60% male Sites Most commonly in axilla, back, mediastinum[pathologyoutlines.com]
  • Neurology and Neurosurgery Czech and Slovak Ophthalmology Czech and Slovak Psychiatry Czech Geriatric Review Czech Gynaecology Czech Rheumatology Czech Dental Journal Czech Urology Czech-Slovak Dermatology Czecho-Slovak Pathology Czech-Slovak Pediatrics Epidemiology[prolekare.cz]
Sex distribution
Age distribution

Pathophysiology

  • We describe the case of an intramuscular hibernoma and illustrate the pathophysiology of the observed hibernoma in relation to recent insights on physiological BAT.[ncbi.nlm.nih.gov]
  • Pathophysiology Pathophysiology involves cytogenic abnormalities of chromosomes 11q13-21 and 10q22, which can cause a deletion in the MEN-1 gene. Structural rearrangements involving the long arm of chromosome 11 are characteristic.[dermatologyadvisor.com]

Prevention

  • These tumors are by definition benign entities but, given their propensity for growth over time, they require complete extirpation to prevent recurrence.[ncbi.nlm.nih.gov]

References

Article

  1. Ucak A, Inan K, Onan B, et al. Resection of intrapericardial hibernoma associated with constrictive pericarditis. Interact Cardiovasc Thorac Surg. 2009;9(4):717-719.
  2. Furlong M, Fanburg-Smith J, Miettinem M. The morphologic spectrum of hibernoma: a clinicopathologic study of 170 cases. Am J Surg Pathol. 2001;25(6):809–814.
  3. Lee J, Gupta A, Saifuddin A, et al. Hibernoma: MRI features in eight consecutive cases. Clin Radiol. 2006;61(12):1029–1034.
  4. Dursun M, Agayev A, Bakir B, et al. CT and MR characteristics of hibernoma: six cases. Clin Imaging. 2008;32(1):42–47.
  5. Murphey M, Carroll J, Flemming D, et al. From the archives of the AFIP: benign musculoskeletal lipomatous lesions. Radiographics. 2004;24(5):1433-1466.
  6. Cypess A, Lehman S, Williams G, et al. Identification and Importance of Brown Adipose Tissue in Adult Humans. N Engl J Med. 2009;360:1509–1517.
  7. Drevelegas A, Pilavaki M, Chourmouzi D. Lipomatous tumors of soft tissue: MR appearance with histological correlation. Eur J Radiol. 2004;50(3):257–267.
  8. Ritchie D, Aniq H, Davies A, et al. Hibernoma—correlation of histopathology and magnetic-resonance-imaging features in 10 cases. Skeletal Radiol. 2006;35(8):579-589.
  9. Chatterton B, Mensforth D, Coventry B, et al. Hibernoma: intense upstake seen on Tc-99m tetrofosmin and FDG positron emission tomographic scanning. Clin Nucl Med. 2002;27(5):369–370.
  10. Angervall L, Nilsson L, Stener B. Microangiographic and histological studies in 2 cases of hibernoma. Cancer. 1964;17:685-692.
  11. Lele M, Chundru S, Chaljub G, et al. Hibernoma. Arch Pathol Lab Med. 2002;126(8):975-978.
  12. Mrózek K, Karakousis C, Bloomfield C. Band 11q13 is nonrandomly rearranged in hibernomas. Gen Chrom Cancer. 1994;9(2):145-147.

Ask Question

5000 Characters left Format the text using: # Heading, **bold**, _italic_. HTML code is not allowed.
By publishing this question you agree to the TOS and Privacy policy.
• Use a precise title for your question.
• Ask a specific question and provide age, sex, symptoms, type and duration of treatment.
• Respect your own and other people's privacy, never post full names or contact information.
• Inappropriate questions will be deleted.
• In urgent cases contact a physician, visit a hospital or call an emergency service!
Last updated: 2019-07-11 22:41