Calcified synovial metastasis in the knee from renal cell carcinoma: a case report

We present the case of an 83-year-old man who had painful swelling of right knee for 6 months. Radiographs showed a large intra-articular soft-tissue mass with small calcifications, whereas MRI detected a multilobulated intra-articular tumor with bone erosions at the distal femur. Histopathology of ultrasound-guided biopsy specimen of the synovial mass revealed it to be a poorly differentiated metastatic carcinoma. Abdominal computed tomography with intravenous contrast medium administration found a heterogeneously enhancing large right renal mass with calcifications, which was shown to be a renal cell carcinoma on histopathology. No metastases were found elsewhere. To our knowledge, this is the first reported case with MRI findings of a calcified intra-articular synovial metastasis from renal cell carcinoma.

Skeletal radiology. 2016 Oct 20 [Epub ahead of print]

Michael McConnell, Rajendra Kumar, Behrang Amini, Patrick P Lin, Wei-Lien Wang

Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, 1515- Holcombe Blvd, Unit 1475, Houston, TX, 77030, USA., Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, 1515- Holcombe Blvd, Unit 1475, Houston, TX, 77030, USA. ., Department of Orthopaedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA., Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.