EGFL6 and meningioma: The mean serum EGFL6 concentration was 672, 139, and 135 pg/ml in patients with meningiomas classified as WHO grade I (benign), grade II (atypical), and grade III (anaplastic) respectively, indicating a significant increase of serum EGFL6 level in benign meningioma patients when compared with atypical (P<0.001) or anaplastic meningioma patients (P<0.001) (Table 1).