CSPG4 and oligodendroglial tumor: NG2/CSPG4 immunoreactivity was significantly associated with EGFR gene amplification (p = 0.0005, Fisher’s exact test) in malignant gliomas and with 1p/19q-codeletion in oligodendroglial tumors (p = 0.0297, Fisher’s exact test) (Table 3).