The correlation between PR expression and Ki67 MIB-1 was studied in 10 reviewed series; 5 (12, 19, 22, 24, 34) found significantly lower PR expression in meningiomas with higher Ki67-Li; on the other hand, others (23, 30, 33, 36, 39) did not find significant differences. This evidence concerns the gene MKI67 and meningioma.