The purpose of this study is to develop tests that will allow us to determine who will react differently to the drugs used to treat cancer. We also want to see who will react differently with preparing for a bone marrow transplant.

The title of this study is interindividual genetic variability as a determinant of chemotherapy toxicity and response in pediatric oncology/bone marrow transplantation patients. We will collect blood from pediatric oncology/bone marrow transplantation patients who are going to receive chemotherapy in order to assess several defined genetic polymorphisms that may be involved in chemotherapy toxicity and response. The polymorphisms will be assessed on normal mononuclear cells by a combination of techniques. We will determine whether these polymorphisms occur in pediatric oncology/bone marrow transplantation patients and their correlation with different clinical features during and following therapy including toxicity and response. The presence or absence of polymorphisms will be correlated with patient outcome and tumor recurrence.

Inclusion Criteria:

• All Pediatric Oncology and Bone Marrow Transplantation Service patients with a histologically proven tumor for whom there is an intent to treat with chemotherapy are eligible for participation in this study. The patient does not need to be newly diagnosed for enrollment on this protocol.
• All patients or their guardians must provide written informed consent. Minors will be required to provide assent.

Exclusion Criteria:

• None

All Pediatric Oncology and Bone Marrow Transplantation Service patients with a histologically proven tumor for whom there is an intent to treat with chemotherapy