Chondrosarcoma With Atypical Clinical Presentation Treated by Gamma Knife Radiosurgery for Multiple Brain Metastases —Case Report—

A 60-year-old male was first treated for World Health Organization (WHO) grade II chondrosarcoma arising from the ring finger manifesting as painful swelling. Four years later, the patient presented with cerebral infarction. Echocardiography revealed a tumor occupying the left atrium. He underwent open heart surgery and the tumor was identified as metastatic chondrosarcoma with malignant transformation to WHO grade III lesion. Five months following the cardiac surgery, the patient suffered generalized seizure. Cerebral magnetic resonance imaging revealed multiple parenchymal lesions. Surgical tumor extirpation confirmed the histological diagnosis as metastatic grade III chondrosarcoma. Gamma knife radiosurgery (GKS) performed postoperatively controlled the parenchymal lesions for more than 10 months without relapse. GKS may be effective for the treatment of brain metastasis from high grade chondrosarcoma.