Is progesteron receptor status really a prognostic factor for intracranial meningiomas?

• Progesterone receptor expression is more commonly found in benign meningiomas.
• The mean MIB-1 index and the mean mitotic index are higher in malignant meningiomas compared to benign meningiomas.
• Tumor grade, but not progesterone receptor expression, is correlated with meningioma behaviour.

ObjectivePresence of steroid hormone receptors in meningiomas is well-known, but their correlation with tumour behaviour is unclear. The purpose of this study was to assess the relation between steroid hormone receptor expression and tumour behaviour.MethodsWe retrospectively reviewed 48 patients undergoing surgery for intracranial meningioma between January 2002 and December 2004. We included World Health Organization (WHO) Grade I meningiomas in Group 1 and WHO Grades II and III in Group 2. Tumour grade, progesterone receptor (PR), oestrogen receptor (ER) expressions, MIB-1 Index and Mitotic Index were assessed. We sought the correlation between tumour grade and MIB-1, Mitotic Indices, and also PR expression. Furthermore, the correlation between PR expression and MIB-1 and Mitotic Indices was assessed in Group 1 and Group 2, separately.Results26 patients were in Group 1 and 22 patients in Group 2. PR expression was determined in 56% of the tumours while there was no ER expression. PR expression was found to be higher in Group 1 compared to Group 2. The Mean MIB-1 Index and the Mean Mitotic Index were significantly higher in Group 2 compared to Group 1. However, when Groups 1 and 2 were assessed separately, PR expression does not appear to be correlated with MIB-1 and Mitotic Indices in benign and also in non-benign meningioma groups.ConclusionOur findings suggest that tumour grade, but not PR expression, is correlated with meningioma behaviour.