Fig. 3.

Diffuse astrocytoma, World Health Organization grade 2, IDH1 R132H mutant. A 42-year-old woman experienced numbness in both lower extremities for about 3 years and numbness in the right upper extremity and muscle weakness in the right lower extremity for 2 months. Magnetic resonance imaging (MRI) revealed an intramedullary spinal tumor at the C5–T3 levels. The tumor diffusely expanded with high signal intensity on T2-weighted MRI (A, C, D) and without any enhancements on gadolinium-enhanced T1-weighted MRI (B). It was difficult to identify a distinct surgical plane for the tumor, and partial removal was achieved. The tumor was diagnosed as diffuse astrocytoma, IDH1 R132H mutant. Forty-two months later, MRI showed no evidence of tumor growth (E), and her symptoms were stable.