An unusual cause of tree-in-bud pattern: pulmonary intravascular tumor embolism caused by chondrosarcoma.

We report the case of a 45-year-old man who initially presented with chondrosarcoma of the left femur that was treated surgically. Follow-up chest computed tomography (CT) performed 3 years later showed multiple small nodules with a tree-in-bud branching pattern and larger elongated opacities with beaded contours. These findings raised the suspicion of intravascular tumor embolism.