|Year : 2016 | Volume
| Issue : 3 | Page : 144-145
Giant adrenal myelolipoma containing mature bone tissue: An extremely rare case
Sanjeev Kumar Shukla, Shivya Parashar
Department of Radiodiagnosis, Government Medical College and Associated Group of Hospitals, Kota, Rajasthan, India
|Date of Web Publication||7-Oct-2016|
Dr. Sanjeev Kumar Shukla
Department of Radiodiagnosis, Government Medical College and Associated Group of Hospitals, Kota - 324 001, Rajasthan
Source of Support: None, Conflict of Interest: None
Adrenal myelolipoma is an unusual, benign, and biochemically inactive tumor that is composed of mature adipose and hematopoietic tissue. The presence of mature bone spicules within the lesion is extremely rare. Very limited number of cases of myelolipoma containing bone tissue has been reported in the world literature. We report a rare case of giant adrenal myelolipoma containing mature bone tissue.
Keywords: Bone spicules, giant, mature bone, myelolipoma
|How to cite this article:|
Shukla SK, Parashar S. Giant adrenal myelolipoma containing mature bone tissue: An extremely rare case. MAMC J Med Sci 2016;2:144-5
|How to cite this URL:|
Shukla SK, Parashar S. Giant adrenal myelolipoma containing mature bone tissue: An extremely rare case. MAMC J Med Sci [serial online] 2016 [cited 2020 Sep 19];2:144-5. Available from: http://www.mamcjms.in/text.asp?2016/2/3/144/191679
| Introduction|| |
Giercke in 1905 first described, and 24 years later, Oberling coined the term "myelolipoma."  Myelolipoma has usually been found in the adrenal gland, but extra-adrenal locations are also known. Adrenal myelolipomas are usually noted in the late adult life and affect males and females equally.  With an incidence of 0.08-0.2%, myelolipomas account for 3-5% of all primary tumors of adrenals. Most lesions are asymptomatic and discovered incidentally. Myelolipoma consists of mature fat interspersed with hematopoietic elements resembling bone marrow. The presence of mature bone spicules within the lesion is extremely rare as reported in our case.
| Case Report|| |
A 42-year-old female with a history of hypertension presented with right upper quadrant abdominal pain for few days. On physical examination, a palpable lump was noted in the right flank region. Ultrasonography of the abdomen showed a large hyperechoic mass lesion with internal calcific foci in suprarenal area displacing right kidney inferiorly. Noncontrast computed tomography (CT) of the abdomen revealed a large mass (18 cm × 13 cm) in the retroperitoneum, superior and medial to the right kidney, displacing kidney inferolaterally. Mass showed a large area of fat density (−80 HU-−120 HU), with internal soft-tissue dense foci and septations. Large mature bone spicules were seen in the periphery and center of the lesion, a rare finding. Location and CT attenuation of the mass suggested right adrenal myelolipoma [Figure 1]. Fine-needle aspiration cytology from the lesion confirmed the diagnosis of myelolipoma. Surgery was performed through a right subcostal incision for the extraperitoneal approach of the right adrenal gland. The mass was totally dissected from the right kidney and excised. Macroscopic examination of the mass revealed bone spicules.
|Figure 1: Giant adrenal myelolipoma in a 42-year-old female with a history of hypertension and right upper quadrant pain. (a) Axial. (b) coronal noncontrast computed tomography images show large predominantly fat-containing lesion (asterisk) arising from right adrenal gland displaces right kidney inferolaterally. Mature bone spicules are seen within the lesion (yellow arrow). (c) Axial noncontrast computed tomography image of the bone window shows mature bone spicules (yellow arrow) within the lesion|
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| Discussion|| |
Adrenal myelolipoma is a tumor-like lesion composed of variable amounts of mature adipose tissue and bone marrow elements. In spite of white blood cell and red blood cell precursors such as megakaryocytes, it does not serve as a hematopoietic source. The adrenal gland is the most common site; myelolipoma may occur in retroperitoneum around the kidney and presacral space or in liver. Unilateral involvement is more common. Myelolipomas on CT appear as well-delineated heterogenous attenuation masses with low-density (<−30 HU) fat tissue interspersed with more dense areas of myeloid tissue. , The size of the tumor is usually <5 cm and giant myelolipoma is rare. The majority of incidentally discovered myelolipomas are small and asymptomatic although large symptomatic lesions are also reported in the adult population. Calcification is seen in about 27%. Symptoms may be due to pressure effect of the large tumor, tumor necrosis, and intralesional hemorrhage. Spontaneous retroperitoneal hemorrhage is usually the most common complication of adrenal myelolipoma. Malignant potential of adrenal myelolipoma has not been reported. 
Myelolipoma and myeloadiposis are closely associated and are in fact the expression of a single process that is both focal (myeloadiposis) and diffuse (myelolipoma).The process consists of the differentiation of choristomatous primitive mesenchymal cells into hematopoietic tissue, adipose tissue, and in rare cases, bone tissue. 
A fatty adrenal mass is diagnostic of myelolipoma with a possible differential diagnosis of adrenal adenoma, lipoma, angiomyolipoma, and retroperitoneal sarcoma. If CT shows nonhomogenous characteristics or if the diagnosis is in doubt, an image-guided needle fine biopsy could be performed to confirm the diagnosis. , Surgical excision is unnecessary unless the diagnosis is unclear or the lesion is symptomatic. Asymptomatic, nonhemorrhagic myelolipomas do not require therapy.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
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