Brief Answer:
Kidney cysts are usually benigns

Detailed Answer:
Hello,

I understand your concern. From your question it is not clear what is the reason you did a CT scan. Was it done because you were having kidney pain, or was it found casually. Most of the time, kidney cysts, which are fluid filled sacs,are not painful and are not felt, and they are casually discovered on ultrasound.
They are usually benign, but when they grow in size they can cause pain and discomfort on the side. However, whenever they are discovered, cysts need further investigation to determine the size and whether they are solitary or there is a presence of other cysts. Solitary cysts, are most commonly a benign presence.
The treatment, when the cyst is big enough to cause discomfort, is either puncturing it with a needle, to empty the fluid or surgery.
I recommend you do see the urologist for further investigation and for peace of mind.

I hope this helps.
I'd be glad to answer any further questions you might have.
Wishing you good health and all the best.

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