Ependymoma with extensive lipidization mimicking adipose tissue: a report of five cases.
Lipomatous ependymoma is a recently described entity and only 3 cases of this variant have been reported in the literature. We report 5 cases of this rare variant of ependymoma. Patients age ranged from 4 years to 45 years and, interestingly, all of them were males. Two tumors were supratentorial in location, 2 in the fourth ventricle and 1 was intramedullary. Microscopically all of them showed the classical histology of ependymoma along with lipomatous differentiation. The lipomatous component was composed of cells with a large clear vacuole pushing the nucleus to the periphery and giving a signet ring cell appearance. This component demonstrated positivity for GFAP and S-100 protein thereby confirming its glial lineage. Three of the 5 tumors were high grade (WHO-grade III), had a high MIB-1 labelling index (MIB-1 LI) and showed recurrence on follow-up. However, 2 were low grade (WHO grade II) and patients are free of disease till the last follow up.
All India Institute of Medical Sciences, Department of Pathology, New Delhi, 110029, India.
M C
MC
Sharma
R
R
Arora
R
R
Lakhtakia
A K
AK
Mahapatra
C
C
Sarkar
D000273:Adipose Tissue / Q000473:pathology*; D000293:Adolescent; D000328:Adult; D001932:Brain Neoplasms / Q000378:metabolism / Q000473:pathology*; D002551:Cerebral Ventricle Neoplasms / Q000473:pathology; D002675:Child, Preschool; D004806:Ependymoma / Q000378:metabolism / Q000473:pathology*; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D015192:Infratentorial Neoplasms / Q000473:pathology; D050356:Lipid Metabolism; D008297:Male; D008875:Middle Aged; D009418:S100 Proteins / Q000032:analysis; D013120:Spinal Cord Neoplasms / Q000473:pathology; D014617:Vacuoles / Q000473:pathology
D005904:Glial Fibrillary Acidic Protein; D009418:S100 Proteins