Presentation
Progressive painful swelling the medial aspect of the left knee.
Patient Data
There is an expansile soft tissue mass arising from the medial metaphysoepiphyseal region of the distal femur with a cortical breach and extension to the adjacent soft tissues of the knee, surrounding the medial collateral ligament and extending to the medial aspect of the intercondylar notch. It shows a low signal on T1, inhomogeneous high signal on T2 with a peripheral hypointense rim, and edematous infiltration of the surrounding bone marrow. The postcontrast sequences show a heterogeneous enhancement with a peripheral rim-like corresponding most likely to the fibrovascular septation between lobules of hyaline cartilage.
Case Discussion
MRI features of a tumoral mass of the medial metaphysoepiphyseal region of the distal femur with cortical breach and extension to the adjacent soft tissues of the knee, pathologically proven as a low grade (grade I) chondrosarcoma.