A process being developed to freeze testicular tissue from boys who have not gone through puberty, to save for future infertility treatment. Tissue that contains cells that make sperm is removed from the testicles through a small incision (cut). It is then frozen and stored. At a later date, the tissue can be thawed to retrieve sperm. Testicular tissue cryopreservation is being studied as a type of fertility preservation. It may be useful for young boys who are going to have treatments that may cause infertility, such as certain cancer treatments. Also called testicular tissue banking and testicular tissue freezing.