• To estimate prevalence of neurologic symptoms as reported by the patient or parent in childhood acute lymphoblastic leukemia survivors. [ Time Frame: At lease 5 years from diagnosis and at least one year after completion of therapy. ] [ Designated as safety issue: Yes ]
  
• To estimate prevalence of neurologic signs as determined by detailed neurologic examination of childhood acute lymphoblastic leukemia survivors. [ Time Frame: At lease 5 years from diagnosis and at least one year after completion of therapy. ] [ Designated as safety issue: Yes ]
  

• To estimate prevalence of neurologic disability as determined by neurologic symptoms, signs and administered questionnaire instruments. [ Time Frame: At lease 5 years from diagnosis and at least one year after completion of therapy. ] [ Designated as safety issue: Yes ]
  
• To explore risk factors for development of neurologic disability. [ Time Frame: At lease 5 years from diagnosis and at least one year after completion of therapy. ] [ Designated as safety issue: No ]
  
• To assess effect of neurologic disability on quality of life. [ Time Frame: At lease 5 years from diagnosis and at least one year after completion of therapy. ] [ Designated as safety issue: No ]
  

Acute lymphoblastic leukemia (ALL) is the most prevalent childhood malignant disease. Survival has improved from 5-10% in the early 1960s to over 80% at present. Historically, the central nervous system (CNS) was the most common site of leukemia relapse. However, major improvement in cure rates was achieved with the addition of CNS directed therapy using initially craniospinal irradiation, and more recently, a combination of high-dose systemic methotrexate and intrathecal chemotherapy.

ALL mostly afflicts children in the first 12-years of life, an age when progressive myelination is taking place and the central nervous system is more vulnerable to chemical and radiologic injury. Many ALL studies have reported neurologic adverse events related to the treatment.

Little is known about the long-term outcome of neurologic toxicity developing during treatment of leukemia, or development of new late onset neurologic complications. No data is available about outcomes of non-behavioral/cognitive neurologic complications, such as seizures, incoordination, headache, loss of motor or sensory function, impaired energy and muscle weakness. In addition, there is no data available on impact of neurologic disability on quality of life of ALL survivors.

It is important to understand and recognize neurologic disability, its causes and impact on function and quality of life so that adequate and timely remedies can be offered through education and appropriate interventions can be undertaken to help prevent long-term morbidity.

This is a prospective observational study of ALL St. Jude Children's Research Hospital survivors to determine the prevalence of different headache syndromes, as defined by International Society of Headache criteria (IHS) and the prevalence and severity of seizures and their relationship to leukemia treatment. We will establish incidence, type, severity, and disability of sensory-motor neuropathy when present or any long term progression of initial peripheral nerve injury in ALL survivors. This study will also help define whether there is a higher incidence of low back pain and if there is any relation to a specific treatment.

Subjects will have a one-time evaluation with an investigator administered questionnaire and a neurologic examination.