Transient vertebral enhancement secondary to superior vena cava obstruction mimicking bone metastases
Presentation
Epigastric pain and vomiting. Chest radiograph showed mediastinal widening.
Patient Data
Large heterogeneously enhancing mass with necrotic component seen in the antero-superior mediastinum extending to hilar regions (more on the left). No calcifications or fat component within. This mass is encasing the aortic arch and its branches. It is also encasing and compressing the left pulmonary artery, left superior pulmonary vein, left brachiocephalic vein and superior vena cava. Multiple dilated collateral veins are seen in the anterior and lateral right chest wall. The mass also surrounds the trachea and proximal main bronchi with tracheal narrowing. No clear plane with the left second chondral cartilage anteriorly and pericardium inferiorly. The mass appears separate from the thyroid gland superiorly.
Enlarged nodes are seen at left cardio-phrenic and right hilar regions.
The heart is not enlarged. Moderate pericardial effusion noted.
Emphysematous lung changes. No focal lung nodules.
Apart from a left renal cyst, rest of the solid organs show no focal lesions.
Apparent hyperdense/sclerotic lesion within the T9 vertebra, not seen in the delayed scan suggestive of transient vertebral enhancement. There is also an enlarged right paravertebral vein seen. No other suspicious bony lesion.
IMPRESSION: Large antero-superior mediastinal mass with local infiltration causing mass effect as well as vascular and airway encasement and compression.
Apparent hyperdense/sclerotic lesion within the T9 vertebra, not seen in the delayed scan suggestive of transient vertebral enhancement (blue arrows).
Case Discussion
This patient has a large mediastinal mass causing superior vena cava obstruction with multiple dilated collateral veins in the anterior and lateral chest wall. The transient T9 vertebral enhancement via the basivertebral venous plexus is due to intraosseous collateral venous flow/enhancement and may mimic sclerotic bone metastases 1,2. This pseudo-pathologic vertebral enhancement may demonstrate nodular or polygonal patterns and tends to involve the central portion of the vertebral bodies 3.
Differential diagnosis of antero-superior mediastinal masses are the 5Ts - thymus, thyroid, thoracic aorta, terrible lymphoma and teratoma/germ cell tumors. In this case, the mass is not continuous with the thyroid gland and is not arising from the thoracic aorta. Thymic tumor, lymphoma or germ cell tumor might be considered, however this conglomerate mass involves the prevascular and visceral compartments of the mediastinum with marked mass-effect on normal structures, therefore small cell lung cancer should also be included in the differential diagnosis.
Unfortunately, this patient succumbed prior to obtaining histology.
Unable to process the form. Check for errors and try again.