This x-ray shows a malignant bone tumor (osteogenic sarcoma) of the knee. This type of tumor is usually seen in adolescents (around 15 years old). This tumor extends from the bone into the surrounding tissue.
Update Date 3/23/2014
Updated by: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.