Tuesday 19 February 2013

Ewing's Sarcoma

Sorry about the long hiatus, but here is something that came up a couple of weeks ago which was a bit tragic for the patient, but at the same time quite an interesting case.

I personally have not seen a gallium whole body scan like this, and likewise with the other technologists in the department.  This patient was being worked up for Ewing's sarcoma.  

When the patient arrived in our department, they were in a considerable amount of pain.  We limited the SPECT/CT to only 1 bed as oppose to our regular whole body SPECT/CT which covers 2 to 3 bed positions on our Symbia T6.  Having said that, it was quite obvious where the tumour was located.

Fig. 1  Ga-67 whole body image of a patient being worked up for Ewing's sarcoma.  The right  thoracic area has intense gallium uptake.
The right thorax contained majority of the gallium uptake, with little evidence of metastases outside of the area.  However, the CT demonstrated a much clearer extent of the disease involvement with the spine and the surrounding bony structures.  The patient originally was asymptomatic, but as the disease started to spread, a rapid loss in weight occurred and discomfort emerged from the right posterior region of the back.

Fig. 2  Transaxial CT slice.  Notice the periosteal reaction in the posterior rib and spine.

Fig. 3  Sagittal slice with an almost complete opacification of the right lung.  Most of the lung has collapsed due to the right sided mass and effusion.

Fig. 4  A coronal slice further depicting the multiple lytic changes in the right sided ribs as well as the invasion of the tumour into the spinal canal.
Overall the disease state was quite extensive with an extra large parenchymal mass filling up much of the right hemithorax, measuring up to 13 cm in thickness.  The disease may have started in the spine or in one of the ribs and over time became invasive.  A further MRI of the spine was performed to assess the spinal canal and spinal cord as the patient began to have bilateral leg weakness and tingling in the feet.

Generally with Ewing's sarcoma it often occurs during childhood and can start anywhere in the body.  However it tends to target the long bones, that are hard, dense bones that provide strength, structure, and mobility.  Almost a third of the patients have some metastases to other locations, generally to the lungs and in to other bones.  Click on the above link (Ewing's sarcoma) for more information.