LGCmain
Indian Journal of Pathology and Microbiology
Home About us Instructions Submission Subscribe Advertise Contact e-Alerts Ahead Of Print Login 
Users Online: 2922
Print this page  Email this page Bookmark this page Small font sizeDefault font sizeIncrease font size
IJPM is coming out with a Special issue on "Genitourinary & Gynecological pathology including Breast". Please submit your articles for these issues


 
  Table of Contents    
LETTER TO EDITOR  
Year : 2019  |  Volume : 62  |  Issue : 3  |  Page : 503-505
An unusual presentation of mediastinal myelolipoma: A Radiologico-Pathological correlation


1 Department of Pathology, Lab Medicine and Transfusion Medicine, Medanta - The Medicity Hospital, Gurgaon, Haryana, India
2 Department of Radiology, Medanta - The Medicity Hospital, Gurgaon, Haryana, India

Click here for correspondence address and email

Date of Web Publication26-Jul-2019
 

How to cite this article:
Sachdev R, Goel RK, Goel S, Ahlawat K. An unusual presentation of mediastinal myelolipoma: A Radiologico-Pathological correlation . Indian J Pathol Microbiol 2019;62:503-5

How to cite this URL:
Sachdev R, Goel RK, Goel S, Ahlawat K. An unusual presentation of mediastinal myelolipoma: A Radiologico-Pathological correlation . Indian J Pathol Microbiol [serial online] 2019 [cited 2019 Aug 19];62:503-5. Available from: http://www.ijpmonline.org/text.asp?2019/62/3/503/263473




Editor,

A 53-year-old female presented with features of Gastro-esophageal reflux disease (GERD), referred from outside with history of hiatus hernia. The patient had normal blood counts (hemoglobin: 14.2 g/dL; WBC: 6.77 × 103/uL; Platelets: 160 × 103/uL) and normal coagulation profile. Contrast Enhanced Computed Tomography (CECT) was done and the findings revealed a large predominantly fat containing oval lesion with scattered calcific foci and a non-enhancing soft tissue component in right retrocrural region (coronal section), measuring 11.8 × 6.9 × 6.9 cm, extending superiorly into the lower chest extra pleural region along the right paravertebral location, abutting the inferior vena cava, esophagus and aorta into the lower chest (Sagittal and Axial section), suggestive of a lipoma/liposarcoma. Under CT guidance, biopsy from right sided posterior mediastinal mass lesion was done under local anaesthesia by using 18G biopsy needle. These cores show mature adipose tissue with fragment of bone and bone marrow elements. The marrow elements comprise of all three lineages including myeloid, erythroid and megakaryocytic lineage. No immature components or an increase in blasts seen as demonstrated by CD34 and CD117 [Figure 1]. There were no features of malignancy/infiltration. Overall, a diagnosis of myelolipoma was given. The differentials considered include myelolipoma, teratoma and foci of extramedullary hematopoiesis (EMH). In view of a normal hematological profile, a possibility of EMH was less likely. These biopsies do not contain other germ cell line representation, thus teratoma was excluded.
Figure 1: CECT shows the coronal, sagittal and axial view of the large posterior mediastinal mass measuring ~12 cm, predominantly comprising of adipose tissue. (a) Low magnification showing admixture of mature adipose tissue and marrow elements (H and E, ×20). (b and c) High magnification showing the predominance of mature marrow elements including myeloid interspersed with erythroid clusters and inset showing megakaryocytes (H and E, ×40). (d and e) Highest magnification showing the mild eosinophil predominance and erythroid clusters (H and E, ×100x). CD34 and CD117: Few scattered blasts (×100)

Click here to view


Myelolipoma were first described in 1905 and named in 1929. They are unusual benign neoplasm composed of mature adipose tissue and hemopoietic elements. Myelolipoma are usually seen in the adrenal glands and the incidence in extra adrenal sites varies from 0.08%-0.2% at autopsy. Atypical sites of origin include the presacral region, retroperitoneum, liver, spleen, stomach, greater omentum, leptomeninges, and mediastinum, where myelolipoma is discovered accidentally.[1] They are typically non-functioning and asymptomatic.[2] Primary mediastinal myelolipoma are extremely rare (~3%), posterior mediastinum being more common amongst other mediastinal areas.[1],[3] The posterior mediastinal myelolipoma are predominantly symptomatic (75% of cases) with the common symptoms being cough, chest pain and dyspnoea.[1] Large mediastinal myelolipoma may present with pressure symptoms which are usually vague including back and abdominal pain.[3] There are currently 4 hypotheses regarding the pathogenesis of the myelolipoma. Most theories indicated the development and differentiation of either ectopic adrenal or hematopoietic stem cell receiving triggering stimulus (obesity, hypertension, chronic inflammation, endocrine disorders), another theory was evolution of myelolipoma from metaplastic change of embryonic primitive mesenchymal cells or embolism of bone marrow cells through the blood stream. The third theory was that that majority of tumors were attached to vertebral bodies, haematopoietic tissue might project from vertebral microfractures to paravertebral space. Ectopic haematopoietic tissue may include stem cells that would be the origin of myelolipoma formation. The fourth hypotheses was based on the chromosomal translocation (3; 21) which related to development of acute myeloid leukemia and myelodysplastic syndrome. Thus, in such case myelolipoma might be a neoplastic phenomenon as a result of chromosomal mutation.[1]

CT and magnetic resonance imaging (MRI) are useful diagnostic tools, and gives some clues towards the diagnosis of myelolipoma. Few authors have reported Fine needle aspiration under CT guidance, followed by confirmation by tissue histomorphology to confirm the diagnosis and can definitely rule out malignancy.[1],[2] However, FNAC is not advised in posterior mediastinal tumor due to the complication of haemorrhage, pneumothorax or injury to the spine. In the present case patient presented with features of GERD, CECT showed a large mass in the posterior mediastinum with a predominant adipocytic component with the differential diagnosis of lipoma/liposarcoma. The histopathology confirmed a diagnosis of myelolipoma and excluded liposarcoma. Thus a close correlation between the radiological findings and histopathological findings helped reach the right diagnosis. There is no standard modality of treatment for this tumor and according to the literature large myelolipoma (>7 cm), like in the present case should be removed surgically.[2] The present case is a good example of the radiological and pathological correlation, which enabled us to give the correct diagnosis to the patient. In a tertiary care set up where malignancies are commonly diagnosed with posterior mediastinal tumors being predominantly malignant in nature, a rare benign tumor tends to get over diagnosed, hence the need for strict vigilance and awareness of these entities.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
   References Top

1.
Xiong Y, Wang Y, Lin Y. Primary myelolipoma in posterior mediastinum. J Thorac Dis 2014;6:E181-7.  Back to cited text no. 1
    
2.
Geng C, Liu N, Yang G, Qi M, Chen W. Primary mediastinal myelolipoma: A case report and review of the literature. Oncol Lett 2013;5:862-4.  Back to cited text no. 2
    
3.
Shi Q, Pan S, Bao Y, Fan H, Diao Y. Primary mediastinal myelolipoma: A case report and literature review. J Thorac Dis 2017;9:E219-25.  Back to cited text no. 3
    

Top
Correspondence Address:
Ritesh Sachdev
Department of Pathology and Laboratory Medicine, Medanta - The Medicity Hospital, Gurgaon - 122 001, Haryana
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/IJPM.IJPM_295_18

Rights and Permissions


    Figures

  [Figure 1]



 

Top
 
 
  Search
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
    Email Alert *
    Add to My List *
* Registration required (free)  


    References
    Article Figures

 Article Access Statistics
    Viewed33    
    Printed1    
    Emailed0    
    PDF Downloaded4    
    Comments [Add]    

Recommend this journal