Due to the hidden location of kidney, early stage kidney tumor often has no manifestation, no feeling, and no symptoms. Once hematuria, lumbar pain and lumbar mass (lump) appear, it is likely that the kidney tumor has already reached advanced stage (probably metastasis). With the rapid development of imaging technology, it is not difficult to diagnose kidney tumor at an early stage, as long as regular medical checkups are done (once every six months or once a year at the hospital). If there is any suspicion in ultrasound, further CT examination (plain scan plus enhancement) is recommended to establish the diagnosis.