Cysts of the kidney, if they are described as simple cysts, are benign. Cysts that are less than one centimeter in size are almost always benign. You should clarify with your surgeon or primary care physician that this is a simple cyst. If it is determined to be a simple (rather than complex) cyst, then there is no need to be concerned about this finding. One in four individuals develop simple cysts in their kidneys as they age.
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