Osteosarcoma of the Femur Presenting with Intravenous Tumoral Thrombus

Published Online:https://doi.org/10.1148/rycan.230051

A 35-year-old man with history of a mass in the left lower thigh presented with recent onset of pain. Radiograph revealed a densely ossified soft-tissue mass epicentered around the lower femur (Figure, A). CT angiography showed a large soft-tissue mass with exuberant osteoid-type matrix mineralization centered at the distal metaphysis (Figure, B) which appeared hypointense at T2-weighted MRI (Figure, C and D). Osteosarcoma was the primary consideration in the differential diagnosis. In addition, imaging identified an elongated, tubular, calcified lesion that was in continuity with the mass at distal metaphysis and extended into the dilated popliteal vein, creating a filling defect, which is characteristic of a tumor thrombus (Figure, BD). Biopsy revealed chondroblastic osteosarcoma with 50% necrosis.

Images in a 35-year-old male patient with osteosarcoma of the femur. (A)                 Lateral radiograph, (B) sagittal reformatted CT angiogram, and (C, D) sagittal                 T2-weighted MRI scans of the knee revealed a large sclerotic soft-tissue mass                 centered in the distal metaphysis of left femur with an osteoid-type matrix                 mineralization (A, D). An elongated, calcified tubular structure extending from the                 mass (red star) suggests calcified tumor thrombus in the popliteal vein, causing its                 dilatation (B, C). The mass and tumor thrombus appear hypointense at MRI due to the                 osteoid component, features suggestive of osteosarcoma with tumor-in-vein (C, D).                 The observation of continuity between the thrombus and the primary mass, as well as                 the similarity in signal pattern for both, suggested a malignant thrombus rather                 than a bland thrombus (arrow, D).

Images in a 35-year-old male patient with osteosarcoma of the femur. (A) Lateral radiograph, (B) sagittal reformatted CT angiogram, and (C, D) sagittal T2-weighted MRI scans of the knee revealed a large sclerotic soft-tissue mass centered in the distal metaphysis of left femur with an osteoid-type matrix mineralization (A, D). An elongated, calcified tubular structure extending from the mass (red star) suggests calcified tumor thrombus in the popliteal vein, causing its dilatation (B, C). The mass and tumor thrombus appear hypointense at MRI due to the osteoid component, features suggestive of osteosarcoma with tumor-in-vein (C, D). The observation of continuity between the thrombus and the primary mass, as well as the similarity in signal pattern for both, suggested a malignant thrombus rather than a bland thrombus (arrow, D).

Chondroblastic osteosarcoma is a rare, deleterious subtype of osteosarcoma that accounts for approximately 25% of all cases. These tumors have a high propensity for intravascular spread, leading to life-threatening tumor thrombi (1,2). Malignancies typically induce a hypercoagulable state, which further increases incidence of thrombosis. Distinguishing tumor from bland thrombus is essential to ensure appropriate therapeutic decisions, as patients with tumor thrombus may have a contraindication to anticoagulants (2). Management includes a multidisciplinary approach coordinated by the oncology team (3).

Disclosures of conflicts of interest: R.Y. No relevant relationships. S.G. No relevant relationships.

Keywords: CT, Biopsy, Needle Aspiration, Skeletal-Appendicular

Authors declared no funding for this work.

References

  • 1. Purandare NC, Dua SG, Rangarajan V, Shah S, Sharma AR. Pulmonary artery and femoral vein tumour thromboembolism in a patient with osteogenic sarcoma demonstrated by FDG PET/CT. Eur J Nucl Med Mol Imaging 2010;37(3):653.
  • 2. Prakash A, Puranik AD, Purandare NC, Agrawal A, Shah S, Rangarajan V. Pelvic venous thromboembolism leading to pulmonary embolism in a case of chondroblastic osteosarcoma detected on FDG PET/CT. Indian J Nucl Med 2021;36(2):231–232.
  • 3. Almeida E, Mascarenhas BA, Cerqueira A, Medrado AR. Chondroblastic osteosarcoma. J Oral Maxillofac Pathol 2014;18(3):464–468.

Article History

Received: Apr 11 2023
Revision requested: Apr 11 2023
Revision received: May 23 2023
Accepted: May 31 2023
Published online: July 21 2023