Mri of spine showed two simple cysts in left kidney 2 years ago the largest was 3cm this recent mri read as follows: 2 circumscribed T2 hyperintense homogenous nonenhancing simple cysts in left kidney; largest measures 4cm and is partially exophytic in lateral upper pole. Should I be concerned the one has grown 1cm over two years and is now partially exophytic I also have multiple Sclerosis