Figure 3.

Radiographic evolution of TN and PP over time. T1+ contrast axial magnetic resonance imaging scans from representative patients with TN (A–C) and PP (D–F) depicting radiographic evolution of treatment‐related changes over time. (A): Woman aged 37 years with anaplastic oligoastrocytoma status post (s/p) chemoradiation. Onset of biopsy‐confirmed TN at 13 months after radiotherapy (RT), presenting as multiple contrast‐enhancing lesions (seven total) associated with new neurological symptoms. Gradual regression of lesions under bevacizumab treatment. (B): Man aged 64 years with anaplastic astrocytoma s/p RT. At 28 months after RT, onset of multiple periventricularly located, contrast‐enhancing lesions (four total) was noted. Follow‐up by imaging surveillance showed near total radiographic resolution of all lesions within 1 year of onset without treatment. The dominant left periventricular enhancing lesion is highlighted in the serial scans. (C): Woman aged 43 years with anaplastic astrocytoma s/p chemoradiation. Onset of biopsy‐confirmed TN at 11 months after chemoradiation (chemo‐RT), presenting as multiple contrast‐enhancing lesions (nine total) associated with new neurological symptoms, managed with steroids. Eight of nine lesions radiographically resolved within 6 to 26 months of onset. The dominant right periventricular lesion is shown. (D): Man aged 39 years with glioblastoma multiforme (GBM) s/p chemoradiation. Increased contrast enhancement around the resection cavity (RC) noted at 3 months after chemo‐RT during active antineoplastic treatment. The lesion was associated with new neurological symptoms and was managed with steroids and surgical debulking at 7 months after onset, revealing extensive tissue necrosis. (E): Woman aged 65 years with GBM s/p chemoradiation. Increased contrast enhancement around the RC noted at 1 month after chemo‐RT during active antineoplastic treatment. The lesion was associated with new neurological symptoms, managed with steroids, partially debulked (4 months after onset), and resolved at 9 months after onset. Histopathology revealed predominant tissue necrosis with few and scattered residual tumor cells. (F): Man aged 66 years with GBM s/p chemoradiation. Increased contrast enhancement around the RC noted at 1 month after chemo‐RT during active antineoplastic treatment. The lesion was associated with new neurological symptoms, managed with steroids, and fully resected at 4 months after onset, revealing extensive tissue necrosis.

Abbreviations: PP, pseudoprogression; TN, treatment‐induced brain tissue necrosis.