PSEUDOPROGRESSION IN A PATIENT WITH ANAPLASTIC EPENDYMOMA AFTER RADIATION THERAPY

Ependymoma is a brain tumor that develops from ependemic cells that lining the inside of all the ventricles of the brain. Ependymomas are twice as likely to appear in the region of the posterior cranial fossa. Pseudoprogression is a change that develops after surgical and/or chemoradiotherapy, caused by vascular changes leading to a transient increase in the permeability of the BBB. These changes coincide with early delayed reactions to radiotherapy and are considered as a subacute reaction of the brain. On MRI, there is a transient occurrence of foci that accumulate contrast for several weeks to 6 months or more after chemoradiotherapy. Dynamic control shows an improvement, which confirms the absence of true tumor growth. Changes take place without specific treatment. In the article, we give a rare clinical observation that shows the importance and effectiveness of dynamic MRI monitoring in differential diagnosis.

anaplastic ependymoma, pseudoprogression, BBB, MRI, post-contrast enhancement, PET, radiotherapy, polychemotherapy

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