3-year-old boy presenting with
exopthalmos
Lananh Nguyen, M.D.
Division of Neuropathology
University of Pittsburgh Medical Center
Clinical history
• Patient presented to the PCP complaining of right eye
swelling. Given the patient’s history of allergies,
antihistamines were prescribed without improvement.
• A few weeks afterwards, patient presented to the ED with
right eye protrusion and erythema.
• Physical exam showed intact vision.
• And imaging was performed.
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Radiology: Identify the lesion and name the 3 imaging
modalities used below.
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Radiology: Imaging of the skull lesion. Identify the lesion
and name the 3 imaging modalities used below.
T1
T1 with contrast
T2
This is an extraaxial (nonbrain) mesenchymal lesion
invading into the orbital space
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A biopsy was performed and an intraoperative consultation
was requested.
Click on the link for the whole slide image of the
smear , scan the virtual slide and try to
formulated a differential diagnosis.
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A biopsy was performed and an intraoperative consultation
was requested. What do you see on the smear?
Low power
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A biopsy was performed and an intraoperative consultation
was requested. What do you see on the smear?
Low power
It is lesional
and
abnormally
hypercellular
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High power smear. What do you see on the smear? Benign
or malignant?
High power
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High power smear. What do you see on the smear? Benign
or malignant?
High power
Small blue cells
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Mitosis
These are the permanent H&E slides.
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These are permanent H&E slides.
High power
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Is it benign or malignant?
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Is it benign or malignant?
• Malignant
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What is your differential diagnosis?
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What is your differential diagnosis?
• Small round blue cell tumor
–
–
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–
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Ewings Sarcoma/ Primitive neuroectodermal tumor
Neuroblastoma
Rhabdomyosarcoma
CNS Primitive neuroectodermal tumor
Lymphoma
Atypical teratoid rhabdoid tumor
Ependymoma
What stains would you order?
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These are the stains the pathologist ordered.
– Ewings Sarcoma/ Primitive neuroectodermal tumor – CD99
– Neuroblastoma – Pgp 9.5, synaptophysin or chromogranin
– Rhabdomyosarcoma – myogenin, desmin, smooth muscle actin,
vimentin
– CNS Primitive neuroectodermal tumor – GFAP
– Lymphoma – CD3, CD20
– Atypical teratoid rhabdoid tumor – INI
– Ependymoma – EMA, p53
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Immunohistochemical stains
CD99
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Immunohistochemical stains
synaptophysin
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What do you see on the stains?
• CD99 was strongly and diffusely positive
• Synaptophysin showed diffuse but patchy cytoplasmic
staining
• Vimentin (not shown) highlighted vessels
• INI (not shown) was intact
• All other stains (not shown) in panel were negative
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What is your final diagnosis?
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What is your final diagnosis?
• Final diagnosis:
– Ewings Sarcoma/Primitive Neuroectodermal tumor
– FISH studies were positive for t(11;22).
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Discussion
Many translocations have been identified for Ewing’s sarcoma. The table lists
the most commonly identified ones with t(11;22) as the most common.
Adapted from
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Discussion
• The prognostic factors for increased survival and response
to treatment are:
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–
–
–
–
–
–
–
Female gender
Younger children (<10 years old)
Small tumor size or volume
Tumor location (axial worse than extremities)
Decreased serum lactate dehydrogenase (LDH)
No metastasis
Lack of overexpression of p53
Low Ki67 proliferation index
• The 5-year survival rate has increased over the same time
from 59% to 76% for children younger than 15 years and
from 20% to 49% for adolescents aged 15 to 19 years.[Smith MA,
Seibel NL, Altekruse SF, et al.: Outcomes for children and adolescents with cancer: challenges for the twenty-first century. J Clin
Oncol 28 (15): 2625-34, 2010.]
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