Pseudoprogression versus true progression in glioblastoma patients: A multiapproach literature review

• Glioblastoma is the most common malignant brain tumor in adults with poor prognosis. • Distinguishing pseudoprogression from true progression is a considerable challenge. • Pseudoprogression predictive factors remain necessary to assist clinical decisions. • A review of clinical and histological pseudoprogression markers was performed. • Treatment response assessment criteria were discussed. With new therapeutic protocols, more patients treated for glioblastoma have experienced a suspicious radiologic image of progression (pseudoprogression) during follow-up. Pseudoprogression should be differentiated from true progression because the disease management is completely different. In the case of pseudoprogression, the follow-up continues, and the patient is considered stable. In the case of true progression, a treatment adjustment is necessary. Presently, a pseudoprogression diagnosis certainly needs to be pathologically confirmed. Some important efforts in the radiological, histopathological, and genomic fields have been made to differentiate pseudoprogression from true progression, and the assessment of response criteria exists but remains limited. The aim of this paper is to highlight clinical and pathological markers to differentiate pseudoprogression from true progression through a literature review.