Over the past years many studies have been done for children with kidney tumors. Researchers now know that there are some features of kidney tumors that may help predict how subjects will respond to therapy. 
The purpose of this study is:
• To find out information about patients' tumors to help study doctor know which is the best treatment for their tumors with the least side effects.
• To study kidney tumors so that we may learn more about them and find out more about how to treat patients who have these tumors.  We hope that as more information is learned, we can continue to improve treatments.
• To store tumor tissue, samples of blood and urine from subjects with kidney tumors so that researchers can do more studies in the future.