Quiz Case #1
An 11-year-old boy presented with a painful and mildly swollen right shoulder. Physical examination revealed the presence of mild joint effusion.
Pay attention to the
AGE, SKELETAL LOCATION
Plain film shows a
, radiolucent lesion in the proximal humeral
with subarticular extension. The lesion is partially surrounded by a
. The cortex is intact. The growth plates are open.
MRI is helpful in delineating the lesion.
Microscopic appearance of the curettage specimen, low magnification
Q1. What is your diagnosis?
Giant cell tumor
Q2. Which finding is considered pathognomonic for this entity?
Presence of a cartilaginous matrix
Atypical giant cells
Q3. Neoplastic cells of this tumor are expected to stain positive with:
Low molecular weight cytokeratin
Q4. This tumor is:
This is a self-assessment test. The results are neither collected nor stored.