Fig. 2A–B.

A 77-year-old man had a history of left groin pain for 3 months. His pain progressively increased during the last weeks, even at rest, with substantial volume enlargement of the proximal left thigh. The physical examination disclosed pain with left hip movements and a palpable soft tissue mass on the anteromedial thigh. (A) An AP radiograph of his left hip shows a large lytic lesion with central calcifications and ill-defined borders on the proximal femur. (B) A coronal T2 MR image shows the same cartilaginous tumor with extensive compromise until the subtrochanteric area and medial soft tissue mass. This was interpreted as intermediate- or high-grade malignant by all evaluators.