Patients with glioma soon after radiotherapy show an increase in the size of the original imaging-enhancing lesion or even a new imaging-enhancing lesion that gradually regresses without any further treatment, a phenomenon that resembles tumor progression and is referred to as pseudoprogression. This phenomenon was first described by Hoffman WF in 1979 and was reintroduced by de Witt in 2004 as the number of glioma radiotherapy and concurrent chemotherapy cases increased.