gamma knife surgery again??

My husband had surgery in 2002 and they removed a large atypical meningioma from his parietal region.  He  had a 30 treatment course of radiation following that.  Within the tumor bed, he had another meningioma appear in 2005, then 2007 and now again in 2008.  In 2005 and 2007 he had gamma knife radiation.  With this tumor currently, they are considering gamma knife again.  Firstly, how many times can one safely have gamma knife?  The fact that the meningiomas are coming more often now - does that mean it may have changed from atypical to malignant?  If so then conventional surgery could be a better route to go?  He is recently experiencing some significant personality changes so I am concerned with him having gamma again as it takes so very long to shrink the tumor and have him back to normal.  Any thoughts would be appreciated.  Thanks

[Fernando Roque, MD]

Hi.  Although meningiomas are considered as benign tumors, they do have a propensity for recurring.  The fact that the meningioma has reappeared does not mean that it has transformed into a malignant tumor.  I don't know how many times one can safely have gamma knife surgery.  It might be best to ask your husband's radiation oncologist (the doctors handling the gamma knife) about this.  For recurrent meningioma which is resistant to radiation treatment, your husband has the option for chemotherapy, either with irinotecan, temozolomide or sustained release somatostatin.  You can ask your husband's oncologist if these options are appropriate for him.