Familial Investigations of Childhood Cancer Predisposition

NOTE: This is a research study and is not meant to be a substitute for clinical genetic testing. Families may never receive results from the study or may receive results many years from the time they enroll. If you are interested in clinical testing please consider seeing a local genetic counselor or other genetics professional. If you have already had clinical genetic testing and meet eligibility criteria for this study as shown below, you may enroll regardless of the results of your clinical genetic testing. DEFINITION OF FAMILIAR CANCER FOR THIS PROTOCOL: In this protocol, the definition of "Familial Cancer" is met if any of the following is present: * An individual with a history of cancer diagnosed under 26 years of age who has at least one first, second or third degree relative with a history of cancer diagnosed under 51 years of age; OR * An individual who has been diagnosed with more than one cancer, at least one of which was diagnosed under 26 years of age; OR * An individual with a clinical or molecular diagnosis of a known cancer predisposition syndrome; OR * An individual with a congenital cancer diagnosed before 6 months of age; OR * An individual with a rare pediatric cancer or tumor diagnosed before 26 years of age º Excluding human papilloma virus-associated cervical cancer and non-melanoma skin cancer occurring in adults. INCLUSION CRITERIA: * An individual who meets this protocol's definition of "Familial Cancer," as above. * Biologic relatives of an individual meeting this protocol's definition of "Familial Cancer," who are either affected or unaffected by cancer. EXCLUSION CRITERIA: * An inability or unwillingness of the research participant or his/her legally authorized representative (LAR) to provide written informed consent. * The participant has received allogeneic bone marrow transplantation and has NO pre-transplant germline (cancer-unaffected) DNA available AND is unwilling to provide a skin sample.