Description
The upper end of the tibia is occupied and expanded by tumour showing a rather whorled
appearance; although the tumour appears circumscribed, it is in fact extending through the
periosteum on the front of the tibia and through the articular cartilage into the joint space superiorly.
There is an irregular cavity present in the centre which represents the end result of necrosis.
Histologically the lesion is poorly differentiated.