Glioblastoma is the most common primary malignant brain tumor in adults and it is associated with a dismal prognosis (median survival time of patients only 3 to 9 months after first recurrence). Current standard of care is STUPP scheme : surgical resection followed by radiotherapy (RT) and concomitant and adjuvant temozolomide (TMZ) chemotherapy. What are the main problems of brain tumors? Infiltrating tumors,
indistinct borders Difficult to differentiate tumor infiltration,
PSEUDOPROGRESSION is a subacute treatment (RT-TMZ or RT alone) related reaction with or without clinical deterioration. Most patients are clinically asymptomatic despite the increase of tumor enhancement. There is a pronounced local tissue reaction with an inflammatory componente,
edema and abnormal vessel permeability. NEW OR INCREASED CONTRAST ENHANCEMENT ON MRI Gold standard for distinguishing pseudoprogression and early progression is histopathological analysis or to perform follow-up...
Findings and procedure details
Problematic analysis of pseudoprogressions: At conventional imaging : Pseudoprogression: self-limited enhancing lesions that spontaneously stabilize and resolve without treatment. True progression. During the first 12 weeks after RT+QT or RT alone: New enhancement outside radiation field Pathologic confirmations of progressive disease Subependymal enhancement With conventional techniques,
in most cases it is not possible to differentiate pseudoprogression and true progression. At DWI:...
Accurate differentiation between pseudoprogression and true progression remains challenging for optimal treatment. Diffusion and perfusion MRI may demonstrate different diagnostic values for predicting pseudoprogression in treated gliomas.
Amaya Hilario Department of Radiology.
Neuroradiology section. Universitary Hospital 12 de Octubre,
Hygino da Cruz Jr LC,
Pseudoprogression and Pseudoresponse: Imaging Challenges in the Assessment of Posttreatment Glioma.
AJNR 2011;32:1978-85 2.
Diffusion and Perfusion MRI to Differentiate Treatment-Related Changes including Pseudoprogression from Recurrent Tumors in High-Grade Gliomas with Histopathologic Evidence.
AJNR Am J Neuroradiol 2015;36:877-85. 3.