The purpose of this study is to gain knowledge about how to best diagnose and treat tumors, how tumors affect normal tissue and how treatment of tumors with radiation therapy and chemotherapy affect tumors.

The purpose of this research study is to observe the changes within the tumor cells which may improve the understanding of how tumors grow and how they respond to various treatments. These changes will be compared with results of the physical examination and scans (CT and MRI) that are done as part of clinical care. Images will be made showing the distribution throughout the body of substances containing a small amount of radioactive material. This procedure is called a PET scan. The radioactive substances (tracer compound) in this study are [F-18] FLT.

Inclusion Criteria:

• All patients with neuroblastoma or suspected neuroblastoma seen at Children's Hospital of Michigan (CHM). Patients need to be 2 years or older to be eligible for the initial study
• Patients must be 1 day to 21 years old, there is no gender limit.
• Diagnosis: All patients with neuroblastoma or suspected neuroblastoma, including newly diagnosed and relapsed patients, are eligible for Objective 1. To be eligible for Objective 2, patients must have a diagnosis of neuroblastoma verified by histology or demonstration of clumps of tumor cells in bone marrow with elevated urinary catecholamine metabolites, and have measurable disease after the initial surgery
• Female adolescent patients must have a negative pregnancy test within 14 days of first imaging and should not be pregnant
• Patients must be able to lie still for the tests, or have no contraindication for sedation
• Patients or their legal guardian must sign an informed consent indicating that they are aware of the investigational nature of this study
• A total number of 40-50 patients will be included in the study

Exclusion Criteria:

• Patients who do not have a histology diagnosis of neuroblastoma are not eligible for the study
• Patients whose definite diagnosis after surgery is not consistent with the diagnosis of neuroblastoma will be included in the Objective 1 but excluded for Objective 2.