Indian Journal of Radiology and Imaging Indian Journal of Radiology and Imaging

GENITOURINARY IMAGING
Year
: 2004  |  Volume : 14  |  Issue : 3  |  Page : 301--302

Adrenal myelolipoma : A case report


F Haque, SPB Harish, I Ahmad, A Qamar, H Pandey 
 Department of Radiodiagnosis, Jawaharlal Nehru medical college, A.M.U, Aligarh-202002, India

Correspondence Address:
F Haque
41-Alig Appartment, Shamshad Market, Aligarh-202 002
India




How to cite this article:
Haque F, Harish S, Ahmad I, Qamar A, Pandey H. Adrenal myelolipoma : A case report.Indian J Radiol Imaging 2004;14:301-302


How to cite this URL:
Haque F, Harish S, Ahmad I, Qamar A, Pandey H. Adrenal myelolipoma : A case report. Indian J Radiol Imaging [serial online] 2004 [cited 2019 Aug 24 ];14:301-302
Available from: http://www.ijri.org/text.asp?2004/14/3/301/28608


Full Text

 INTRODUCTION



Adrenal myelolipoma is a rare, endocrinologically inactive neoplasm composed of mature adipose tissue and a variable amount of normal haematopoietic elements. It is a benign neoplasm arising from the adrenal cortex.[1],[2]. Most lesions are usually small and asymptomatic[3],[4] while some may present with nonspecific complaints like abdominal or flank pain or as an abdominal mass. Extra-adrenal sites of myelolipomas have also been recognized and they include the presacral retroperitoneum, perirenal retroperitoneum, mediastinum and liver.The most well recognized complication of adrenal tumours is spontaneous retropertioneal haemorrhage. With the advent of Ultrasonography(USG) and Computed Tomography(CT), the diagnosis of the neoplasm, both in asymptomatic and symptomatic patients, have improved remarkably.

We report a case of symptomatic myelolipoma where the diagnosis was made on the basis of radiological features and image guided fine needle biopsy

 CASE REPORT



A 31yr old woman was referred to us with complaints of dull aching, intermittent pain in the right hypochondrium of a few weeks duration.There was no H/O of relation of pain to food intake,nausea and vomiting or icterus.Physical examination revealed a smooth,well defined mass in the right hypochondrium.Blood and Urine examinations were normal.The patient was subjected to an USG of the abdomen which showed a well encapsulated,echogenic,right supra-renal mass of size 11.6x13.1cms.The remainder of the USG was normal.

A CT scan of the abdomen revealed a well circumscribed,heterogenous, non enhancing mass of size12.5x12x11cms in the right supra-renal region causing downward displacement of the right kidney.The lesion showed hypodense areas with CT attenuation values suggestive of fat.The function of both kidneys appeared normal.

A provisional diagnosis of Adrenal Myelolipoma was made. For confirmation of the diagnosis,a CT guided needle biopsy (using 18G) was done which confirmed the diagnosis

 DISCUSSION



Adrenal Myelolipomas are rare, benign, hormonally non functioning tumours with a reported incidence varying between 0.03 and 0.8% [5].The tumour has also been reported to occur in association with endocrine disorders like Cushing's Syndrome,Congenital Adrenal Hyperplasia and Conn's Syndrome[6].Bilateral tumours occur in about 10% of cases. Rarely,these tumours may be symptomatic owing to their size or complications like intratumoural haemorrhage or tumour necrosis. Several theories have been proposed regarding the etiology of these tumours, the most accepted of which is that proposed by Meaglia and Schmidt in 1992. They proposed that Myelolipomas arise due to metaplasia of the reticulo-endothelial cells of blood capillaries in the adrenal gland in response to stimuli such as infection, stress or necrosis [5]. Imaging features of myelolipoma depend on the varying proportion of fat, myeloid element, haemorrhage or calcification present.

USG of the abdomen may be helpful in the diagnosis of Adrenal Myelolipomas due to its ability to differentiate the echogenic, fatty supra-renal mass from the normal kidneys.However USG findings alone cannot be accepted as confirmatory as several other tumours are also echogenic. On CT,Adrenal Myelolipoma is seen as a hypodense, non enhancing lesion with fat attenuation values[5].Calcification may be seen in these masses in upto 30% of cases[7]. However,if CT shows non-homogenous characteristics,the possibility of an underlying malignancy cannot be ruled out and in such a situation,an image guided needle biopsy should be performed to confirm the diagnosis[2]. Magnetic Resonance Imaging(MRI) of Adrenal Myelolipomas characteristically demonstrates a bright signal on TI-weighted and T2-weighted sequences consistent with the presence of fat.The lesion enhances brightly after intravenous administration of gadolinium. Decrease in signal with fat suppression or phase cancellation is confirmatory. Histological examination also helps to rule out other differential diagnosis such as liposarcoma, retroperitoneal lipoma, adrenal adenoma or carcinoma and renal angiomyolipoma.

 CONCLUSION



USG and CT have greatly enhanced the diagnostic accuracy of Adrenal Myelolipomas. Management of these tumours should be individualized. Small asymptomatic tumours are best followed up on a regular basis. Large or symptomatic tumours may be treated by surgical excision and/or adrenalectomy.

References

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