I have a ten year old niece who has been diagnosed with an intramuscular tumor behind the left knee-cap using both MRI and Ultrasoound imaging. The tumor is definitely not a fluid sac. Neither diagnostic tool directly gives information on whether the tumor is benign or not (trying to look on the positive side). Does anyone know how to determine whether the tumor is benign, or can suggest references to read on doing so? Thank you in advance.

Ted

Tumor biopsies are explained on this website:

University of Virginia Health System (http://www.healthsystem.virginia.edu)