Distal radius giant cell tumor

Lytic lesion present in the distal radius extending to the subarticular region There is expansion with cortical thinning but a narrow zone of transition proximally. Pathological fracture through the radial styloid.

Within the distal radius there is a lucent lesion of soft tissue density in a subarticular location. It is expansile with cortical thinning and narrow zone of transition. No calcification within. It does not cross the joint space. Pathological fracture with buckling of the cortex near the radial styloid.

Increased uptake in the right distal radius. No evidence of further lesions. 

Expansile solid lesion of the subarticular distal radius destroying cortex, which measures 2.9 x 2.7 x 3.8 cm (AP x ML x CC). Signal characteristics are low T1, high T2 and homogeneous enhancement. Narrow zone of transition to normal marrow proximally. Tumor destroys cortex on the dorsal surface. Abnormal enhancing tissue within the extensor tendon sheaths in continuity with the solid mass. Tumor also destroys cortex on the volar aspect but is contained by pronator quadratus. Flexor tendons and carpal tunnel contents appears normal. Buckling of the cortex medially and laterally in keeping with pathological fracture and associated soft tissue edema. Conclusion: Distal radius lesion most in keeping with giant cell tumor with evidence of local extension into the extensor compartment.