I am so confused right now......I have been following up a right kidney cyst for four years now. It was found incidentally on a CT scan done for another reason in 2006. It measured approx 1cm and the radiologist noted that it had layering debris or calcium in the wall of the cyst. He recommended I follow up with a renal ultrasound. I had the ultrasound done and it came back as being just under 1cm and echogenic so it they termed it a "small complex cystic tumor". I had two more CT scans (one in 2007 and one in 2008). Both scans reported it still being about 1cm and a complex cyst with no change. Well, I recently had an ultrasound done as I didn't want to expose myself to the radiation of another CT scan if they were just checking size. The dr office just called me and said the report called it a very small, less than 1cm simple cyst. How could this be? how can something that was called complex, now be called simple. I am happy that the report was not bad but I am confused and worried as to what is going on? should I demand another test? oh....I am a 33 yr old female with no history of UTI's or kidney stones (that I know of).