How to edit the regions already being monitored by CLLocationManager

Question

Is there any way to edit a CLCircularRegion in the NSSet returned by monitoredRegions property of CLLocationManager object?

I want to do something like:

NSSet *monitoredRegionsSet = self.locationManager.monitoredRegions;
for (CLCircularRegion *region in monitoredRegionsSet)
{
    //Change radius of every region in monitoredRegionsSet
}