ABCG2 and neoplasm: In samples from the bulk tumor, the median expression scores for ABCB6, ABCG2, FECH and CPOX were 9 (range: 2–12), 8 (range: 3–12), 9 (range: 1–12) and 9 (range: 1–12), respectively, and expression was similar comparing grade 1 and 2/3 meningiomas (p > 0.05 for each).