A cyclist who has pain in the leg

Case Identification

Case ID Number
Benign or Malignant

Clinical case information

Case presentation

41 year old cyclist who has pain in the leg for 6 months. a biopsy of the lesion in the tibia and a CT scan of the chest was performed. What is the diagnosis?

Radiological findings:
The CT scan shows two metastatic nodules.
Laboratory results:
On histologic examination, the tissue from the lesion consists of reddish-brown loculated masses with significant hemorrhage. Microscopically, the lesion has irregular anastomosing vascular channels. The channels are lined by plump endothelial cells without pleomorphism or mitotic activity. Both the background stroma and the cells lining the vascular channels stain positive for reticulum.
Case Answer
Clinical Case Answer