Although classified as benign neoplasms,giant cell tumors are locally aggre
ssive with a high recurrence rate of 30-50%. The histological appearance in
clude osteoclast-like, multinucleated giant cells and round to spindle-shap
ed mono-nuclear stromal cells. These neoplasms predominatly affect adults i
n the third and forth decades of life (70-80%). Giant cell tumors predomina
tly arise in long tubular bones (75-95%) with the majority occurring around
the knee (50%). The next most common site being the distal radius (10%). T
he epicenter of giant cell tumors is in the epiphysis. The radiographic sig
ns of giant cell tumors are a geographical radiolucentcy with no internal m
ineralisationa, a thinning of the cortex, eccentric in the epiphysis of lon
g bones. MRI signs of giant cell tumors are high signal intensity in T2-wei
ghted images, high contrast media enhancement,fluid levels, signs according
to haemorrhage and haemosiderin deposition. CT shows the expanded and thin
ned cortex. Plain radiographs remain the mainstay of diagnosis of giant cel
l tumors. MRI and CT are important for staging and therefore for surgical p
lanning.