An International Study on Pediatric Patients With Rare Tumors.

This international study collects clinical data on children and teenagers with rare tumors that are not commonly studied due to their low incidence. The goal is to build a large database to better understand these cancers and improve future treatment options. **You may be eligible if...** - You are a child or adolescent between 0 and 18 years old - You have been diagnosed with a primary or relapsed rare tumor - You are treated at a participating center - A parent or legal guardian has given written consent **You may NOT be eligible if...** - Written consent from a parent or legal guardian has not been obtained Talk to your doctor to see if this trial is right for you.