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Mahajan, Abhishek; Agarwal, Ujjwal; Shukla, Shreya; Ashtekar, Renuka; Padashetty, Shubham; Khadtare, Rohan; Noronha, Vanita1; Prabhash, Kumar1; Vaish, Richa2

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Cancer Research, Statistics, and Treatment 5(2):p 343-345, Apr–Jun 2022. | DOI: 10.4103/crst.crst_57_22
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CASE HISTORY

A 70-year-old gentleman presented with a 1-month history of swelling and a non-healing lesion on the lip. On clinical examination, an ulcerative lesion was seen on the mucosal aspect of the lower lip, extending up to the right angle of the mouth. Biopsy of the lesion revealed moderately differentiated squamous cell carcinoma. Contrast-enhanced computed tomography (CT) of the head and neck with thorax was suggested for local staging and metastatic workup. The patient was noted to be hepatitis C positive, so an ultrasound of the abdomen was suggested to rule out associated liver pathology. Ultrasound (USG) of the abdomen showed heteroechoic soft tissue surrounding both kidneys with minimal internal vascularity [Figure 1]. CT scan of the abdomen showed a large soft tissue lesion arising from the perirenal fascia with macroscopic fat surrounding both the kidneys [Figures 2 and 3]. No associated renal pelvis was seen.

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Figure 1:
Ultrasonographic images show heteroechoic soft tissue (arrow) surrounding both kidneys with minimal internal vascularity
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Figure 2:
Multiplanar CT showing a large soft tissue lesion arising from the perirenal fascia (arrowheads) with macroscopic fat surrounding both kidneys
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Figure 3:
Axial contrast-enhanced CT image shows lobulated soft tissue lesions in bilateral perirenal spaces with macroscopic fat within

What is the diagnosis and what should be done next? Once you have finalized your answer.

DIFFERENTIAL DIAGNOSIS AND FURTHER MANAGEMENT

Angiomyolipoma, liposarcoma, and extramedullary hematopoietic malignancies are some of the differential diagnoses for myelolipoma of the kidney. One of the most prevalent benign kidney lesions is angiomyolipoma which can coexist with the stigmata of tuberous sclerosis. Typical angiomyolipoma is a triphasic tumor that contains varying quantities of dysplastic blood vessels, spindle and epithelioid smooth muscle cells, and mature adipose components under the lens. Angiomyolipoma with a fat preponderance mimics other fat-containing tumors.[1234] Liposarcoma is a disease that affects middle-aged people, with a peak incidence in the sixth decade and no gender preference. Retroperitoneal liposarcomas are frequently asymptomatic until they have grown to a large size (>15 cm).[567] Anemia, hepatosplenomegaly, and abnormal peripheral blood smears are all hallmarks of extramedullary hematopoietic malignancies. Extra-adrenal myelolipomas are clearly delineated, however, extramedullary hematopoietic tumors are poorly defined and poorly confined.[8] Myeloproliferative diseases and chronic hemolytic anemia are the most common causes. However, our patient was 70 years old, had normal blood tests, no hepatosplenomegaly, and no chronic debilitating disorders or endocrinopathies. He had no stigmata of tuberous sclerosis. On CT scan, the mass was seen to be arising from the perirenal space and was symmetrically present around the bilateral kidneys, thus, ruling out liposarcoma and angiomyolipoma. Since our patient had normal blood tests, no hepatosplenomegaly, and no chronic debilitating disorders or endocrinopathies, extramedullary hematopoiesis was ruled out.

Based on the radiological findings and the absence of other features to suggest an alternative diagnosis, a final diagnosis of extra-adrenal myelolipoma was made. As the patient was asymptomatic, no further management was deemed necessary for the incidentally noted lesions. The patient was subsequently treated for carcinoma of the lower lip and underwent wide local excision of the same.

FINAL DIAGNOSIS

Extra-adrenal myelolipoma.

DISCUSSION

Myelolipomas are rare benign tumors made up of mature adipose tissue and hematopoietic components. Extra-adrenal myelolipomas have been reported in the presacral area, retroperitoneum, pelvis, and mediastinum, however, they are more common in the adrenal glands.[34] We report a case of an extra-adrenal myelolipoma in the perirenal space, which is a rather atypical location. Extra-adrenal myelolipomas are usually asymptomatic and are identified incidentally on an ultrasound, CT scan, or magnetic resonance imaging (MRI) scan for an unrelated diagnosis. However, some patients with myelolipoma have abdominal pain, which might be attributed to intratumoral bleeding, tumor infarction, or mechanical compression from the tumor mass. Ultrasonography shows an ill-defined heteroechoic mass with minimal vascularity within. CT or MRI can both be used to correctly assess a myelolipoma. Due to the diverse proportion of fat within the mass, radiological imaging presents a well-circumscribed mass with a heterogeneous pattern. On CT imaging, fatty tissue is defined by low attenuation (i.e., –25 to 100 Hounsfield units). On T1-weighted MRI images, fat has a high signal intensity, but the myeloid component of these tumors has a low T2-weighted signal. The enhancement pattern depends on the composition of the tumor. Adrenal myelolipomas can be monitored radiographically without treatment because of their distinctive appearance on imaging. A core biopsy should be performed under ultrasound or CT guidance if a definitive diagnosis is required. A biopsy may reveal adipose tissue as well as a variety of hematologic components; nevertheless, distinguishing between extramedullary hematopoiesis and extra-adrenal myelolipoma is challenging, and the clinical picture confirms the diagnosis.

Published research has shown that these may be hamartomas or clusters of choristomatous hematopoietic stem cells that transmigrate into other places during fetal life or a kidney tumor with clonal cytogenetic abnormalities.[4] Although there are no clear radiological criteria for diagnosing extra-adrenal myelolipoma, the imaging traits of adrenal myelolipoma can be used to identify these tumors. In our case, it was an incidental finding in a case of lip carcinoma and the scan was done for staging the lip cancer as part of the metastatic workup. Other differential diagnoses that were kept in mind were angiomyolipoma, extramedullary hematopoiesis, and liposarcoma. As the lesion was bilateral and perirenal in location, the possibility of angiomyolipoma was less likely. Liposarcoma usually presents as a large mass, however, histopathological evaluation is necessary for diagnosis.[5678] The final diagnosis of myelolipoma was established on imaging, and the patient was treated for lip carcinoma.

CONCLUSION

The occurrence of myelolipoma broadens the differential diagnoses of perirenal neoplasms, especially with the substantial use of imaging modalities that are likely to discover additional incidental lesions in this location. Despite the rarity, renal myelolipoma should be included in the differential diagnosis of lesions in this area.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. The patient has given his consent for the images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published, and due efforts will be made to conceal his identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

REFERENCES

1. Agrawal S, Patil A, Singh AG, Ganpule AP, Sabnis RB, Desai MR. Myelolipoma of kidney: A rare extra-adrenal tumor in an unusual site Int J Appl Basic Med Res. 2021;11:60–2
2. Prahlow JA, Loggie BW, Cappellari JO, Scharling ES, Teot LA, Iskandar SS. Extra-adrenal myelolipoma: Report of two cases South Med J. 1995;88:639–43
3. Beraha D, Block NL, Politano VA. Myelolipoma of the kidney J Urol. 1974;112:19–21
4. Bishop E, Eble JN, Cheng L, Wang M, Chase DR, Orazi A, et al Adrenal myelolipomas show nonrandom X-chromosome inactivation in hematopoietic elements and fat: Support for a clonal origin of myelolipomas Am J Surg Pathol. 2006;30:838–43
5. Cano JY, D'Altorio RA. Renal liposarcoma: Case report J Urol. 1976;115:747–9
6. Ghaouti M, Znati K, Jahid A, Zouaidia F, Bernoussi Z, Mahassini N. Renal myelolipoma: A rare extra-adrenal tumor in a rare site: A case report and review of the literature J Med Case Rep. 2013;7:92
7. Shapiro JL, Goldblum JR, Dobrow DA, Ratliff NB. Giant bilateral extra-adrenal myelolipoma Arch Pathol Lab Med. 1995;119:283–5
8. Fowler MR, Williams RB, Alba JM, Byrd CR. Extra-adrenal myelolipomas compared with extramedullary hematopoietic tumors: A case of presacral myelolipoma Am J Surg Pathol. 1982;6:363–74
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