Fig. 1.

Definition of a recurrence pattern. Representative gadolinium-enhanced MRI of anaplastic gliomas. (A) Local recurrence is illustrated in this case of anaplastic oligoastrocytoma with IDH mutation. Ninety-five months after the surgical procedure, local recurrence was found adjacent to the resection cavity (arrow). (B) Distant recurrence is illustrated in this case of anaplastic oligoastrocytoma without IDH mutation. Twenty-three months after the surgical procedure, an enhanced lesion was observed at a location distant from the initial lesion (arrow). Thirty-four months after, the enhanced lesion showed enlargement; thus, the case was confirmed as distant recurrence.